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Background: Bloodstream infections (BSI) are serious diseases in pediatrics and can increase the rate of morbidity and mortality. Blood culture is time consuming and can have false negative results in some case such as the intracellular or fastidious bacteria. This study aimed to evaluate the PCR against automated blood culture with BACTEC.Materials and methods: In this observational cross-sectional study the blood samples of hospitalized children in Mofid Children’s Hospital with bacteremia signs from February to May 2023 were enrolled. The causative bacteria in bacteremia were identified by phenotypic and PCR methods. Results: 150 blood samples were enrolled to identify the presence of bacteremia by BACTEC and PCR. 60% and 40% of samples have negative and positive results in both methods, respectively. PCR showed 100% sensitivity and specificity in detecting bacteremia compared to BACTEC. A variety of bacteria were identified by phenotypic and moleculthods and coagulase negative (CONS) is the most of them.Conclusion: The rapid and accurate detection of bacterial pathogens with the high sensitivity and specificity compared gold standard method are the most important profits of molecular assay.

Blood is a sterile, liquid connective tissue. When infected with microbes, grave consequences can occur, such as shock, multiple organ failure, disseminated intravascular coagulation (DIC), and death. The World Health Organization reported 49 million cases of sepsis and 11 million sepsis-related deaths in 2017, accounting for approximately 20% of deaths annually worldwide. Rapid identification of the causative organism and timely, appropriate treatment are required to reduce mortality due to bloodstream infections. This study was conducted to analyze the patterns of various bacteria causing bloodstream infections and their antibiotic susceptibility patterns. All blood samples received for diagnosing bloodstream infections at the Microbiology Department of Sri Guru Ram Das Institute of Medical Sciences and Research, Amritsar, were included in the study, the duration of which was 1 year, from January to December 2020. Blood samples of 5–10 ml from adult and 5 ml from pediatric patients, were collected under aseptic conditions, stored in BACTEC bottles, and processed in an automated BACTEC system before antimicrobial therapy. After 7 days of incubation, if no microbial growth was observed, the sample was reported as sterile for aerobic organisms. When growth was observed, broth from positive blood culture bottles was subcultured on blood and MacConkey agar for identification and antimicrobial susceptibility testing using Vitek 2 according to CLSI (Clinical Lab Standard Institute) guidelines and the manufacturer’s instructions. A total of 441 (14.5%) bacteria were isolated from 3007 blood samples from patients with suspected bacteremia. Contamination was observed at a rate of 2.5%. Gram-positive cocci (49%) were the predominant organisms recovered, followed by Gram-negative bacilli (34%). Gram-positive cocci were coagulase-negative Staphylococci (46%), Staphylococcus aureus (7%), and Enterococcus spp. (6%). Among the Gram-negative bacilli, E.coli (14%), Klebsiella spp. (13%), Acinetobacter baumannii (7%), Pseudomonas spp. (7%), Salmonella typhi (2%), Enterobacter spp. (1%), and Serratia spp. (1%) and single isolates of Aeromonas spp., Morganella morgani, Pantoea spp., Proteus mirabilis, and Providentia rettgeri were identified. Linezolid, teicoplanin, and vancomycin were the most effective drugs for treating Gram-positive bacteremia. Tigecycline, carbapenems, and aminoglycosides were the most effective treatments for Gram-negative bacteremia. The results stress the need for continued screening and surveillance in routine blood culture techniques to start empiric therapy for bloodstream infections.

Blood is a sterile, liquid connective tissue. When infected with microbes, grave consequences can occur, such as shock, multiple organ failure, disseminated intravascular coagulation (DIC), and death. the World Health Organization reported 49 million cases of sepsis and 11 million sepsis-related deaths in 2017, accounting for approximately 20% of deaths annually worldwide. Rapid identification of the causative organism and timely, appropriate treatment are required to reduce mortality due to bloodstream infections. this study was conducted to analyze the patterns of various bacteria causing bloodstream infections and their antibiotic susceptibility patterns. All blood samples received for diagnosing bloodstream infections at the Microbiology Department of Sri Guru Ram Das institute of Medical Sciences and Research, Amritsar, were included in the study, the duration of which was 1 year, from January to December 2020. Blood samples of 5-10 ml from adult and 5 ml from pediatric patients, were collected under aseptic conditions, stored in BACTEC bottles, and processed in an automated BACTEC system before antimicrobial therapy. After 7 days of incubation, if no microbial growth was observed, the sample was reported as sterile for aerobic organisms. When growth was observed, broth from positive blood culture bottles was subcultured on blood and MacConkey agar for identification and antimicrobial susceptibility testing using Vitek 2 according to CLSI (Clinical lab Standard institute) guidelines and the manufacturer's instructions. A total of 441 (14.5%) bacteria were isolated from 3007 blood samples from patients with suspected bacteremia. Contamination was observed at a rate of 2.5%. Gram-positive cocci (49%) were the predominant organisms recovered, followed by Gramnegative bacilli (34%). Gram-positive cocci were coagulase-negative Staphylococci (46%), Staphylococcus aureus (7%), and Enterococcus spp. (6%). Among the Gram-negative bacilli, E.coli (14%), Klebsiella spp. (13%), Acinetobacter baumannii (7%), Pseudomonas spp. (7%), Salmonella typhi (2%), Enterobacter spp. (1%), and Serratia spp. (1%) and single isolates of Aeromonas spp., Morganella morgani, Pantoea spp., Proteus mirabilis, and Providentia rettgeri were identified. linezolid, teicoplanin, and vancomycin were the most effective drugs for treating Gram-positive bacteremia. tigecycline, carbapenems, and aminoglycosides were the most effective treatments for Gram-negative bacteremia. the results stress the need for continued screening and surveillance in routine blood culture techniques to start empiric therapy for bloodstream infections. [ABSTRACT FROM AUTHOR]

Theoretically, Aspergillus spp. grow in culture media, but frequently, blood cultures of patients with invasive Aspergillosis are negative, even if until now, the reasons are not clear. This aspect underlines the lack of a good strategy for the cultivation and isolation of Aspergillus spp. In order to develop a complete analytical method to detect Aspergillus in clinical and pharmaceutical samples, we investigated the growth performance of two blood culture systems versus the pharmacopeia standard method. At <72 h, all test systems showed comparable sensitivity, about 1–2 conidia. However, the subculture analysis showed a suboptimal recovery for the methods, despite the positive growth and the visualization of the "Aspergillus balls" in the culture media. To investigate this issue, we studied three different subculture approaches: (i) the use of a sterile subculture unit, (ii) the use of a sterile subculture unit and the collection of a larger aliquot (100 µL), following vigorous agitation of the vials, and (iii) to decapsulate the bottle, withdrawing and centrifuging the sample, and aliquot the pellet onto SDA plates. Our results showed that only the third procedure recovered Aspergillus from all positive culture bottles. This work confirmed that our strategy is a valid and faster method to culture and isolate Aspergillus spp. from blood culture bottles. [ABSTRACT FROM AUTHOR]

Although Candida spp are aerobic microorganisms, some Candida strains, mainly Candida glabrata , can be recovered from anaerobic blood culture vials. We assessed the contribution of the anaerobic vials for the diagnosis of candidemia, especially for C. glabrata. We conducted a multicenter retrospective study including eight university or regional hospitals. A single episode of monomicrobial candidemia per patient was included from September 1st, 2016, to August 31st, 2019. The characteristics of all aerobic and anaerobic blood culture vials sampled within 2 h before and after the first positive blood culture vials were recorded (type of vials, result, and for positive vials time-to-positivity and Candida species). Overall, 509 episodes of candidemia were included. The main species were C. albicans (55.6%) followed by C. glabrata (17.1%), C. parapsilosis (4.9%), and C. tropicalis (4.5%). An anaerobic vial was positive in 76 (14.9%) of all episodes of which 56 (73.8%) were due to C. glabrata. The number of C. glabrata infections only positive in anaerobic vials was 1 (2.6%), 1 (11.1%), and 15 (37.5%) with the BACT/ALERT 3D the BACT/ALERT VIRTUO and the BACTEC FX instrument, respectively (P <  0.01). The initial positivity of an anaerobic vial was highly predictive of the isolation of C. glabrata with the BACTEC FX (sensitivity of 96.8%). C. glabrata time-to-positivity was shorter in anaerobic vial than aerobic vial with all instruments. Anaerobic blood culture vials improve the recovery of Candida spp mainly C. glabrata. This study could be completed by further analyses including mycological and pediatric vials. Lay summary Although Candida spp are aerobic microorganisms, C. glabrata is able to grow in anaerobic conditions. In blood culture, the time-to-positivity of C. glabrata is shorter in anaerobic than aerobic vials. Only the anaerobic vial was positive in up to 15 (37.5%) C. glabrata bloodstream infections. [ABSTRACT FROM AUTHOR]

Theoretically, Aspergillus spp. grow in culture media, but frequently, blood cultures of patients with invasive Aspergillosis are negative, even if until now, the reasons are not clear. This aspect underlines the lack of a good strategy for the cultivation and isolation of Aspergillus spp. In order to develop a complete analytical method to detect Aspergillus in clinical and pharmaceutical samples, we investigated the growth performance of two blood culture systems versus the pharmacopeia standard method. At Aspergillus balls” in the culture media. To investigate this issue, we studied three different subculture approaches: (i) the use of a sterile subculture unit, (ii) the use of a sterile subculture unit and the collection of a larger aliquot (100 µL), following vigorous agitation of the vials, and (iii) to decapsulate the bottle, withdrawing and centrifuging the sample, and aliquot the pellet onto SDA plates. Our results showed that only the third procedure recovered Aspergillus from all positive culture bottles. This work confirmed that our strategy is a valid and faster method to culture and isolate Aspergillus spp. from blood culture bottles.

To present our validation study of the BD BACTEC FX blood culture system for sterility testing of cardiovascular tissues aimed for human application. For operational qualification, we performed temperature mapping of the system, vacuum test using non-inoculated BACTEC vials, and growth promotion tests by injecting contaminant strains into aerobic and anaerobic bottles. For performance qualification, negative control, assessment of method suitability, evaluation of sensitivity limits, control of neutralization of antibiotics in biopsy samples from allografts and tissue toxicity effects, were performed. Tissue samples and transport/cryopreservation solutions were homogenized in GentleMACS Dissociator and injected into BACTEC Plus aerobic and anaerobic vials for incubation at 35 °C for 14 days. Tissues were spiked with aerobic and anaerobic bacteria and fungi. Growth of contaminants appeared in all aerobic and anaerobic vials for Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa; in anaerobic vials for Cutibacterium (Propionibacterium) acnes and Clostridium sporogenes; and only in aerobic vials for Candida albicans and Aspergillus brasiliensis. The majority of bacterial strains were detected within two days (59–100%), exceptionally between 3 and 14 days. In contrast, fungal contaminations were detected within 2, 3–6, 7–10 and after 10 days of incubation in 33.3, 71.6, 96.6 and 99.9% of cases,respectively. Uninhibited growth appeared in the tissue biopsies and homogenized tissues with and without antibiotics and in other solutions. BD BACTEC blood culture system with GentleMACS Dissociator is a rapid and efficient tool for detection of contamination in cardio-vascular tissues aimed for human application. [ABSTRACT FROM AUTHOR]

Introduction: This study explores the uses of microcalorimetry to detect Mycobacterium tuberculosis (TB) in sputum. Microcalorimetry measures metabolic heat evolution during cellular proliferation of tuberculosis (TB) and is considered as a possible alternative to conventional diagnostic tools. Objectives: To compare the time to detection (TTD) from the BACTEC™ MGIT™ 960 and the calScreener™ calorimetric system. Methods: Sixty‐four sputa samples were selected from patients with confirmed pulmonary tuberculosis. Those sample were then decontaminated and analysed using calorimetry and BACTEC MGIT 960 system. Results: The incubation period until detection of M. tuberculosis in the sample was 8·5 ± 3·7 days for the MGIT system and 10·1 ± 4·1 days (mean ± SD) for calorimetry. Conclusions: The microincubations in the 48‐well format calScreener offers potential for rapid and accurate diagnostic of TB in different samples. Although TTD from calorimetry is still longer than with the MGIT, our findings suggest that several improvements are possible. Still, the instrument is ideal for continuous, real‐time analysis of net metabolic heat release of limited sample numbers. Significance and Impact of the Study: Our result emphasizes that with further optimization, calorimetry can become an alternative detection method for tuberculosis. [ABSTRACT FROM AUTHOR]

Objectives: Bacteriological diagnosis of septic arthritis (SA) is complicated. Agar plates are the main culture method and yields 40–60% of positive bacterial detection. Addition of bottled culture broth (Bactec®) as a method for detecting synovial microorganisms is common. The advantages of this method and the combination of both have not been thoroughly investigated. This study evaluates an added value of the Bactec culture broth as a single method or as combined with the agar-plate culture. Methods: All culture aspirates of SA-suspected patients were analyzed. All cases with a positive result by either method were reviewed for background data and clinical diagnosis. Results: Out of 5000 synovial fluid samples, a clinical diagnosis of SA was suspected in 1024 cases. Samples processed by both culture methods were extracted during the same event. Bactec® vials were positive for significant bacterial detection in 113/148 cases (76.4%) while agar-plate cultures were positive in only 96/154 (62.3%) representing higher sensitivity of 0.5 vs. 0.42 and a positive predictive value (PPV) of 0.76 vs. 0.62. Bacterial detection by both methods combined was positive in 137/221 (62%) and did not achieve a significant increment. Conclusions: The Bactec® method has many advantages in bacteriological identification of synovial infection, including a broader identification spectrum, faster response time, and superior qualities of identification although being more expensive. This method has a better yield in detecting septic arthritis and might be considered a single method for synovial fluid culture in cases suspected for SA. Key Points • The Bactec method had improved detection rates. • Culturing by agar plates and Bactec revealed higher sensitivity and lower specificity. • The use of the blood culture bottles (Bactec system) alone will raise the detection rate of septic arthritis with lower false positive rates and at lower costs. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to compare microbiological analyses of 100 computed tomography-guided drainages from infectious foci (thoracic, abdominal, musculoskeletal), transported and analyzed by two widely established techniques, that are (i) sterile vials or (ii) inoculated blood culture bottles. The mean number of detected microorganisms from blood culture (aerobic/anaerobic) or conventional method (sterile vial, solid and broth media) per specimen were comparable with 1.29 and 1.41, respectively (p = 1.0). The conventional method showed a trend towards shorter time-to-result (median 28.62 h) in comparison to blood culture incubation (median 43.55 h) (p = 0.0722). Of note, detection of anaerobes (13% vs. 36%) and the number of detected microorganisms in polymicrobial infections (2.76 vs. 3.26) differed significantly with an advantage towards conventional techniques (p = 0.0015; p = 0.035), especially in abdominal aspirations. Despite substantially overlapping results from both techniques, the conventional approach includes some benefits which justify its role as standard approach.

Abstract Objective Campylobacter spp. and Helicobacter spp. are rare but important causes of bacteremia in humans. Distinguishing these bacteria is complicated because of their similar phenotypic profiles. We conducted clinical and microbiological investigations of Campylobacter spp. or Helicobacter spp. bacteremia. Patients diagnosed with bacteremia from 2008 to 2014 were included. The clinical and microbiological characteristics of Campylobacter spp. and Helicobacter spp. bacteremia were compared. The BACTEC system was used in blood cultures. A receiver operating characteristic curve was plotted based on the time to blood culture positivity. Results Sixteen cases of Helicobacter spp. bacteremia (patient age: 61 ± 18 years) and 14 cases of Campylobacter spp. bacteremia (patient age: 49 ± 21 years) were identified. Median time to blood culture positivity was longer for the Helicobacter spp. cases than the Campylobacter spp. cases (91.4 h vs 55.3 h, p 75 h predicted Helicobacter spp. bacteremia with a sensitivity of 0.88 and a specificity of 0.93 (area under the receiver operating characteristic curve of 0.90). In conclusion, a time to blood culture positivity was useful in distinguishing Helicobacter spp. bacteremia from Campylobacter spp. bacteremia.

The diagnosis of bloodstream infection requires the optimum combination of media in an automated blood culture system for maximum recovery of pathogens with the earliest time to detection. In a previous work, we showed that for patients admitted to the Emergency Department of our hospital, the combination of BACTEC lytic anaerobic and BACTEC aerobic vials was more efficient than BACTEC anaerobic and BACTEC aerobic vial. In this study, we extended the work including a broader patient population, representative of all hospital. A total of 8629 cultures were collected during the pre-lytic phase, from 01 July 2013 to 30 June 2014 and 7940 cultures during the post-lytic phase, ranged from 01 July 2015 to 30 June 2016. The number of positive blood cultures was higher during the post-lytic phase (19.74%) than in the pre-lytic phase (17.52%), particularly for Escherichia coli, Staphylococcus spp., Enterococcus spp., and anaerobes. We also observed a significant decreased of the time to detection, with the mean and median in the post-lytic phase of 17.68 and 13.05 h compared with 19.49 and 14.47 h in the pre-lytic phase. Whereas the time to detection was the same for organisms recovered in the aerobic Plus bottles for both time periods, time to detection for the anaerobic lytic bottles was significantly faster than with the anaerobic Plus bottles. This study carried out on a long time observation reported that a simple modification of composition of blood culture set could lead to better results in bloodstream infection detection. [ABSTRACT FROM AUTHOR]

Introduction: India accounts for 25% of the total global TB burden, and a third of the “missing cases” that do not get diagnosed or notified. When health professional in India think of TB, they often order non-specific tests while TB can only be confirmed by microbiological tests such as sputum smear microscopy, Gene Xpert, and cultures. This study was conducted to study the role of image guided biopsy in all suspected Tuberculosis Spine cases, in terms of establishing diagnosis and to study the sensitivity and specificity of diagnostic procedures (biopsy as well as culture methods). Also, the researchers compared the available investigations results of CBNAAT, BACTEC, HPE & AFB Stain. Methodology: The present study was conducted at the Department of Orthopaedics of our institute. It was a prospective study carried out from January 2015 to June 2016. 53 patients presented to us were suspected spinal tuberculosis on Clinico- radiological ground and were posted for bone biopsy. Results: In our study, mean age of the patients is 42.5±14.3 (Range 14–73 years). Out of 53, 34 patients (64.15 %) were male and 19 (35.85 %) were female. Patients have usually presented in early destructive stage of the disease (Type 2) (30/53). We have used USG guided aspiration (04/53), CT guided biopsy (22.64%) and in majority of cases IITV guided biopsy (37/53). 4 of 53 cases were excluded, as they were inconclusive due to inadequate sample obtained during biopsy. Diagnosis was established in 38 out of 53 patients (70.71 %). Sensitivity and specificity of Z-N stain were 42.1%, and 90.9%, of HPE were 81.5% and 90.9%; of BACTEC were 89.4% and 100% respectively. Conclusion: In the present study, it is observed that no single diagnostic modality is having a good negative predictive value. Hence, a combination of diagnostic battery is required for precise diagnosis and better results. The result of BACTEC culture and CBNAAT has detected a maximum of 38 cases. While the result of Z-N microscopy and histopathology has detected small number of cases. As culture takes long incubation time for results, the CBNAAT can be applied for rapid detection of Pott's disease.

Transfusion of blood products is one of the key aspects of hospital care. Among the risk of blood transfusions, bacterial contamination of the blood bags is not so uncommon. Sources of bacteria can be several. Majority of the times the source of bacteria is the arm of the donor. Second important cause of bacterial contamination of blood transfusion, is bacteria in the blood stream of the donor. Donor is usually selected with strict selection criteria. Detailed history is usually taken. Diversion is another method used to reduce the bacterial contamination of blood bags. Temperature is also important parameter for the growth of bacteria. RBCs are stored at 4 ˚C and platelets are stored at 22˚C. For the ideal bacterial detection techniques, it is important that they can detect the bacteria as early and as low as possible. At the time of collection of sample for viral screening, number of bacteria might be too low to be detected. [ABSTRACT FROM AUTHOR]

Purpose Early treatment of septic arthritis is essential before irreversible damage to the articular cartilage occurs. Clinicians often start empirical antibiotic therapy for symptomatic relief while awaiting a definitive culture report. In present day parlance with variations in different centres in the private and public sector and rampant antibiotic abuse, a lot of resistance is being seen in the flora and their sensitivity patterns. Hence it is imperative to document and analyze these changing trends. Methods The authors conducted a retrospective analysis of prospectively gathered data of 60 patients under 14 years of age. Joint arthrotomy was performed as a standard therapeutic protocol and the drained pus or synovial fluid was sent for gram stain and culture by 2 different methods: conventional agar plate method and BACTEC Peds Plus/F bottle method. Antibiotic susceptibility tests were done by the disc diffusion method of Clinical Laboratory Standards Institute (CLSI). Results The commonest presenting age group was below 1 year (80% patients) including 24 neonates. There were 19 hospital and 41 community acquired cases of septic arthritis. The hip (56%) was the commonest affected joint followed by knee (28%), shoulder joint (11%) and elbow (5%). Microorganism was isolated in 53% isolates of joint fluid only (36 culture positive patients). Conventional agar methods of culture showed positive report in only 42% patients (15/36 patients) while with the BACTEC method the yield was 71%. In the Community acquired septic arthritis, methicillin sensitive Staphylococcus aureus was isolated as commonest microbe while resistant variety of gram negative bacilli including E. coli and Klebsiella were found as predominant organism causing hospital acquired nosocomial infection of joints. The results strikingly differ in terms of response to treatment as most patients (11/19 patients) showed significant resistance to the most commonly practiced empirical antibiotic regimen of ampicillin-cloxacillin group in routine practice. When cefazolin was used as empirical antibiotic, it has shown good response and better sensitivity in 82% patients (27/33 patients). Conclusion S. aureus is still the most common organism in septic arthritis. The BACTEC system was found to improve the yield of clinically significant isolates. Though a significant resistance to common antibiotic regimen is noticed, the strain is susceptible to cephalosporin group of antibiotics. We recommend the use of cephalosporine antibiotics as an empirical therapy till culture and sensitivity report are available. [ABSTRACT FROM AUTHOR]

We evaluated the performance of MGIT 960 system in terms of recover rate, detection time of mycobacteria and contamination rate from various human clinical specimens and compared it with already in use BACTEC 460 TB system and conventional LJ medium. This is the first reported study on MGIT 960 and its comparison with BACTEC 460 system in Pakistan. A total of 260 different clinical specimens received for the culture of mycobacteria were dealt during the six months study period. All the specimens were digested and decontaminated according to the standard N-acetyl-Lcysteine NaOH method. All the processed specimens were inoculated on both the liquid systems and solid medium and incubated for six weeks and eight weeks consecutively. A total of 44 mycobacterial isolates (Mycobacterium tuberculosis, n=43; Mycobacteria other than tuberculosis, n=1) were recovered from 260 clinical specimens. The recovery rate of M. tuberculosis complex was 97.6% on BACTEC MGIT 960 system and 93.0% on BACTEC 460 system and 83.7% on LJ medium. The mean detection time of mycobacteria on BACTEC MGIT 960 system was 11.2 days in smear positive cases, 14.2 days in smear negative cases and 14.8 days in smear positive cases on BACTEC 460 system. Contamination rates were 9.6% and 5.6% and 3.4% for BACTEC MGIT 960, BACTEC 460 system and LJ medium respectively. The non-radiometric, fully automated BACTEC MGIT 960 system has better diagnostic ability as compared with radiometric, semi-automated BACTEC 460 system and LJ medium, so it can be used as a reliable alternative in over burden laboratories.

The culture results of 4,807 blood and 383 sterile body fluid specimens received in our laboratory during a 54-month period, were analyzed to determine the time required for culture to become positive, time at which a culture could safely be considered negative, and the spectrum of isolated organisms. The specimens were processed by automated BACTEC 9120 culture system. A total of 1,677 clinically significant microorganisms were isolated. Gram positive and negative bacterial isolation rates were found to be 62.55% and 32.20%, respectively. Yeasts were recovered in 5.24%. False positivity rate was 1.5%. Clinically significant isolates recovered on day four and five were 97.81% and 99.88%, respectively. At day five, the sensitivity was 99.94% and negative predictive value 99.96%. Our data support a five-day incubation protocol for recovery of all clinically significant organisms with sensitivity reduced by 0.06%, when compared with a six-day protocol.

"nBackground: Infectious diseases are problematic in all around the world especially in the developing countries and early diagnosis of infections and one etiologic agents has a major role in the treatment of one patients. There are some culturing methods consist of conventional, semiautomatic and automatic. One of automatic methods is BACTEC system worked by fluorescent technology and Co2 production of organisms in culture media."n"nMethods: This study is based on observational-descriptive method with simple convenient sampling. We analyzed 262 samples of body sterile fluids of patients admitted in pediatric and internal wards of a university (Rasol- Acram) Hospital. They are consisting of 150 blood, 46 synovial, 32 CSF, 24 pleural, and 10 peritoneal samples."n"nResults: There were no differences between two sex in BACTEC and Conventional methods. Average age of patients with positive and negative culture in two methods had not differences. 72 (27.5%) samples were positive that 32 (12.2%) samples only in BACTEC method, 4 (1.5%) in conventional method and 36 (13.7%) in two methods had statistical differences (p=0.003). That means positive cultures are seeing in BACTEC more than Conventional method. Comparison of two methods in positive blood culture samples had statistical differences (p=0.02) but no statistical differences in other body fluids were seen. i. e. positive cultures were seen in BACTEC more than Conventional method. Positive culture in these two methods had statistical differences in antibiotic utilization (p

Background — Presence of microorganisms in sterile body sites leads to life-threatening infections. For early and accurate diagnosis of those infections, cultures of the sterile fluids have to be done. These cultures can not always detect the causative agents due to insufficent number or fastidious growing of the probable microorganisms in the material. Objectives — In this study, it was aimed to compare sterile body fluid cultures which had been processed with both conventional culture methods and BACTEC automatized blood culture system retrospectively. Material and Methods — A total of 138 body fluid cultures were compared retrospectively from the laboratory records. Results — Amongst the specimens, 122 cultures were negative. Nine of the rest 16 specimens were positive with both culture methods and seven cultures were positive with BACTEC only. None of the specimens which were negative in BACTEC system revealed positive with the conventionel method. BACTEC detected significantly higher number of positivity (P

The prevalence of female genital tuberculosis (FGTB) in India has been estimated to be about 19%. Despite an array of diagnostic tests being available, the goal of early diagnosis and treatment remains elusive. The present study was planned to identify better diagnostic tests for early detection of FGTB and also to compare their diagnostic accuracy with the existing standard diagnostic tests in three subsets of gynaecological conditions (infertility, menstrual abnormalities and pelvic inflammatory disease). Total of 90 patients recruited in three groups of 30 each underwent endometrial sampling. The biopsied tissue was sent for histopathological examination, AFB smear examination, culture in Lowenstein-Jensen (L–J) and BACTEC 460 TB culture media and nested PCR testing. BACTEC had a sensitivity of 40% with a specificity of 90% while PCR showed a sensitivity and specificity of 62.5% and 54%, respectively, as compared to conventional methods (L–J culture or histopathology). Addition of PCR to BACTEC improved sensitivity from 40% to 52%. Hence, we conclude that combination of BACTEC and PCR had an improved detection as compared to conventional tests with an advantage of early results. [ABSTRACT FROM PUBLISHER]

Summary Background Pyrazinamide (PZA) is the most important drug against the latent stage of tuberculosis (TB) and is used in both first and second line treatment regimens. The continued increase in multi-drug resistant TB and the prevalence of PZA resistance makes the development of alternative assays for prompt identification of PZA resistance all the more important. Methods We standardized and evaluated a quantitative variant of the Wayne assay (QW) for determining PZA resistance in Mycobacterium tuberculosis strains. This assay quantifies M. tuberculosis metabolism of PZA and production of pyrazinoic acid (POA) using visible spectrophotometry. We evaluated this method using PZA concentrations of 400 μg/ml and 800 μg/ml at incubation periods of 3, 5 and 7 days. M. tuberculosis strains from 68 sputum samples were also tested with the standard Wayne assay, Tetrazolium Microplate Assay (TEMA), Bactec 460TB and pncA sequencing. We compared QW and standard Wayne assay against a dichotomous reference classification using concordant Bactec 460TB and pncA sequencing. Secondarily, we determined the quantitative correlation between both QW values and TEMA's minimum inhibitory concentration (MIC) against Bactec 460TB percentage growth. Results The standard Wayne showed sensitivity of 88% and specificity of 97.5%, giving a Youden Index (YI) of 0.855 against reference tests. The QW showed maximum YI of 0.934 on day 7 at 400 μg/ml PZA with 96% sensitivity and 97.4% specificity. Absorbance OD values for 400 μg/ml PZA were more accurate than 800 μg/ml PZA. Although QW showed high accuracy for PZA susceptibility, it did not correlate quantitatively with Bactec percentage growth. TEMA testing was unreliable and did not correlate with Bactec results. Conclusions The proposed QW assay is an inexpensive method capable of providing standardization and automation of colorimetric PZA resistance testing, with better discriminatory than the standard Wayne assay. [ABSTRACT FROM AUTHOR]

Background: Infectious diseases are a leading cause of morbidity and mortality in developing countries. The aim of this study was to compare the results of blood culture employing the conventional and BACTEC methods for detection of bacterial infection in Taleghani Hospital, Tehran. Materials and Methods: This was a descriptive study carried out for 3 months (March 2014-May 2014) on 272 inpatients. Their blood culture results were analyzed using the two methods (BACTEC and conventional).The results were analyzed using descriptive statistics (frequency, mean and standard deviation) and inferential tests (cross tab) via SPSS version 17 software. Results: The results of 177 cases (94.1%) out of 271 studied subjects were true positive, 11 (5.8%) were false negative, 2 cases (3.15%) were false positive, and 11 cases (6.48%) were true negative. The sensitivity and specificity of the BACTEC test were 84.6 and 94.1, respectively, and the rate of positive blood cultures employing BACTEC method was equal to 100% (22.22) while in the conventional method, positive results were equal to 59.09% (22.13). Conclusion: Both BACTEC and conventional methods have high validity. In order to evaluate the results of blood culture and infection control, experts can use either of these methods to study the results of bacterial blood culture. [ABSTRACT FROM AUTHOR]

Background and Aim: Culture positivity for Mycobacterium tuberculosis complex (MTB) in abdominal tuberculosis (TB) using Lowenstein Jensen medium and Bactec system varies from 25 % to 36 %. Data on the prevalence of drug resistance in primary abdominal TB is scant. Our aim was to study the acid-fast bacilli (AFB) culture positivity rate in primary abdominal TB using Bactec Mycobacterial Growth Indicator Tubes (MGIT) system and the prevalence of drug resistance in these patients. Method: Records of patients with abdominal TB (diagnosed on clinical features, endoscopy, histology, microbiology) seen during the period 2008 to 2013 were retrieved from the Gastroenterology and Microbiology departments. Patients with extra-abdominal TB (five pulmonary, two nodal), adnexal (one), and HIV (one) were excluded from analysis. Results: Of 61 patients, 31 (50.8 %) had a positive AFB culture. In the 30 culture-negative patients, histology showed non-caseating granulomas in 25 patients. Drug sensitivity pattern was analyzed in 18 patients; resistance was detected in eight (14.3 % of all patients and 44.4 % of patients in whom drug sensitivity was done) including three (5.4 % of all subjects and 16.6 % in whom drug sensitivity was available) who were multidrug-resistant. Conclusions: The rate of AFB culture positivity in primary abdominal TB was 50.8 % using Bactec MGIT. Likelihood of drug resistance was seen in 14.3 %, of whom 5.4 % were multidrug-resistant. [ABSTRACT FROM AUTHOR]

Background For the diagnosis of prosthetic joint infection (PJI) automated BACTECTM blood culture bottle methods have comparable sensitivity, specificity and a shorter time to positivity than traditional cooked meat enrichment broth methods. We evaluate the culture incubation period required to maximise sensitivity and specificity of microbiological diagnosis, and the ability of BACTECTM to detect slow growing Propionibacteria spp. Methods Multiple periprosthetic tissue samples taken by a standardised method from 332 patients undergoing prosthetic joint revision arthroplasty were cultured for 14 days, using a BD BACTECTM instrumented blood culture system, in a prospective study from 1st January to 31st August 2012. The "gold standard" definition for PJI was the presence of at least one histological criterion, the presence of a sinus tract or purulence around the device. Cases where > =2 samples yielded indistinguishable isolates were considered culture-positive. 1000 BACTECTM bottle cultures which were negative after 14 days incubation were sub-cultured for Propionibacteria spp. Results 79 patients fulfilled the definition for PJI, and 66 of these were culture-positive. All but 1 of these 66 culture-positive cases of PJI were detected within 3 days of incubation. Only one additional (clinically-insignificant) Propionibacterium spp. was identified on terminal subculture of 1000 bottles. Conclusions Prolonged microbiological culture for 2 weeks is unnecessary when using BACTECTM culture methods. The majority of clinically significant organisms grow within 3 days, and Propionibacteria spp. are identified without the need for terminal subculture. These findings should facilitate earlier decisions on final antimicrobial prescribing. [ABSTRACT FROM AUTHOR]

Background: Tuberculous Lymphadenitis is the commonest form of extra pulmonary tuberculosis and tissue diagnosis is the main stay in the diagnosis of extra-pulmonary tuberculosis. This study was conducted to compare cytology, ZN staining and culture findings of clinically suspected tuberculosis lymphadenitis cases. Methods: In the Present Study clinically suspected cases of Lymphadenopathy were undergone Fine Needle Aspiration. The aspirate were examined cytologically followed by ZN staining and BACTEC culture. Results: The cytology suggestive of tuberculous lymphadenitis was found in 46(76.6%) cases out of total 61 cases. Ziehl Neelsen stain demonstrated acid fast bacilli (AFB) in 14 (22.9%) cases and BACTEC isolated mycobacteria in 36 (59%) cases. Out of 61 cases as many as 15(24.5%) cases yielded pus and in 13 of those cases cytology of tuberculous lymphadenitis was found. Cases from blood mixed aspirate demonstrated AFB positivity in 2 (5.88%) and mycobacteria were isolated in 16 (48.48%) cases and cytology also suggest least numbers of tuberculous lymphadenitis i.e. 21 (63.63%) cases. Seven out of Nine cases of necrosis with or without neutrophils show presence of AFB. Samples having epithelioid cell granuloma with or without necrosis show presence of AFB in 5 (16.66%) and 2 (25%) cases and mycobacteria was isolated in 22 (73.73%) and 5 (62.5%) cases respectively. Conclusion: In spite of the diagnostic pitfalls, the results obtained on analytical examination of the study carried out reinforce the opinion that Fine Needle Aspiration Cytology serves as a potent and accurate diagnostic tool for patients presenting with Lymphadenopathy due to tuberculosis.

Background and objectives: There are limitations in time and technique for isolation of Brucella from patients. We developed a new Brucella culture medium and evaluated its efficiency compared to BACTEC blood culture system and serology. Materials and Methods: A bi-phasic medium containing Urea agar and Brain Heart Infusion was formulated. Appearance of clear red color in liquid phase was the basis of positivity for Brucella. The new medium which is designated as TUMS medium (TUMS refers to Tehran University of Medical Sciences) and BACTEC blood culture vials were inoculated with different concentrations of 20 Brucella strains. The blood samples from 58 suspected patients were tested by both media and serology (Wright and Coombs). Any growth was sub-cultured and suspected colonies were identified by standard methods. Results: The TUMS medium detected more positive samples (100%) than BACTEC (85%) when the organism was suspended at lower concentration (10 CFU). Of 58 blood cultures, 47 (81%) samples tested on TUMS medium (incubation period =4.2 days) and 39 (67.2 %) samples tested on BACTEC (incubation period =3.3 days) were found positive. Conclusion: The TUMS medium was superior to others in detecting the organism from patients with clinical signs or who took medications for >1year. The TUMS medium is easy to prepare and use in endemic areas where resources are limited.

A head-to-head, simultaneous, clinical comparison of BACTEC (Becton Dickinson) and BacT/Alert FAN (bioMérieux) aerobic blood culture media demonstrates that BACTEC has improved recovery of pathogens, septic events, and cultures that had antibiotics administered prior to culture collection.Background. Antimicrobial removal devices in blood culture media are designed to remove antibiotics from the blood culture solution, thereby facilitating bacterial growth. How well these devices function clinically has not been established.Methods. All blood drawn for culture from adult inpatients and emergency department visitors in a level I trauma center was placed in paired BACTEC Plus and BacT/Alert FAN culture media and studied simultaneously, consecutively, and prospectively between 1 February and 30 September 2011. All cultures were processed per standard laboratory protocols.Results. Of 9395 total cultures collected, 1219 (13%) were positive, 831 were included, and 524 (33%) contained pathogens. BACTEC had a 4.5-hour faster detection time (P < .0001), and isolated exclusively 182 of 524 (35%; P < .001) pathogens, 136 of 345 (39%) of the gram-positive cocci (P < .001), 48 of 175 (27%; P = .02) of the gram-negative rods, 101 of 195 (52%) of Staphylococcus aureus (P < .001), and 59 of 120 (49%; P = .004) septic events. If active antibiotics had been dosed 0–4 or 4–48 hours prior to culture collection, the odds of that culture growing in BACTEC were 4.8- and 5.2-fold greater, respectively, than of growing in BacT/Alert (P < .0001). Both were equivalent in the recovery of yeast and when no antimicrobials were dosed.Conclusions. BACTEC media has faster time to detection and increased bacterial recovery over the BacT/Alert media in the following categories: overall growth, pathogens, septic events, gram-positive cocci, gram-negative rods, Staphylococcus aureus, and cultures where antimicrobials were dosed up to 48 hours before culture collection. [ABSTRACT FROM PUBLISHER]

Abstract: Blood culture is the most valuable laboratory test for the diagnosis of bacteremia and sepsis. The BACTEC FX and BacT/Alert 3D automated blood culture systems are commonly used in Korean health care facilities. A controlled clinical evaluation of the resin-containing BACTEC Plus aerobic (BA) and anaerobic (BN), and the charcoal-containing FAN aerobic (FA) and anaerobic (FN) bottles using blood from intensive care unit (ICU) patients was designed. The performances of these 2 systems with media containing particle absorbing antimicrobial agents were evaluated using the culture positivity rate and time to detection (TTD). TTD was collected using data management systems, either the Epicenter (BD Diagnostic Systems) or the hospital laboratory information system. A total of 1539 four-bottle sets were collected from 270 patients in medical and surgical ICUs. Blood culture samples included 1539 bottles each of BA, BN, FA, and FN, and yielded 113 (7.3%), 90 (5.8%), 104 (6.8%), and 80 (5.2%) positive bacterial or fungal isolates, respectively. There were significant differences between the resin-containing BA and BN samples in culture positivity and also between the charcoal-containing FA and FN samples, especially for Escherichia coli (25/27 versus 17/27, P < 0.05) and Acinetobacter baumannii (14/15 versus 7/15, P < 0.05). Significantly shorter recovery time was observed in BACTEC Plus aerobic bottles than in FAN aerobic bottles (17.2 and 24.7 h, respectively) (P < 0.001). [Copyright &y& Elsevier]

Objective: Infections are the major cause of morbidity and mortality in febrile neutropenic patients with malignancy. Rapid diagnostic tests are needed for prompt diagnosis and early treatment which is crucial for optimal management. We assessed the utility of soluble triggering receptor expressed on myeloid cells (sTREM-1) in the diagnosis of bacteremia and fungemia in febrile neutropenic patients. Methods: Sixty-five febrile neutropenic children with malignancy hospitalized in Mofid Children's Hospital during a period of one year from January 2007 were recruited for this cross sectional study (mean age 66.2± 37 months; 35 females and 30 males). Thirty patients (46.2%) had acute lymphoblastic leukemia, 2 (3.1%) acute myeloid leukemia, one (1.5%) lymphoma and 32 (49.2%) were under treatment for solid tumors. Simultaneous blood samples were collected for measurement of serum sTREM-1 levels and for blood cultures which were grown in BACTEC media. Gold standard for the presence of infection was a positive BACTEC culture as a more sensitive method compared to current blood culture techniques. Findings: Blood cultures with BACTEC system were positive in 13(20%) patients (12 bacterial and one fungal culture). The mean serum sTREM-1 level in BACTEC positive patients was 948.2±592.9 pg/ml but in BACTEC negative cases it was 76.3±118.8 pg/ml (P<0.001). The optimal cut-off point of sTREM-1 for detecting patients with positive result of BACTEC was 525 pg/ml with sensitivity and specificity of 84.6% and 100%, respectively. Conclusion: Our study revealed a significant association between serum sTREM-1 level and bacteremia and fungemia in febrile neutropenic patients suffering malignancy with acceptable sensitivity and specificity. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To highlight the spectrum of clinical manifestations, labs, complications, treatment and outcome of brucellosis. Methods: Retrospective study was conducted in Kasturba Medical College, Manipal University, Karnataka, India which included 68 confirmed cases of brucellosis from January 2006- April 2010. Diagnosis of brucellosis was made by culturing the sera/body fluids by standard BACTEC method (or) by testing the sera for Brucella agglutinins using the standard agglutination test (SAT). A titer of 1:320 or more was considered as significant. SPSS 16 was used for statistical analysis and Microsoft Excel for graphical representation. Results: Of the 68 patients, 46 (68%) were male and 22 (32%) were female patients with age distribution of 9–75 years. Forty four (64.7%) had history of contact with unpasteurized dairy products or infected animals. Symptoms included fever (68, 100%), myalgia (21, 31%), musculoskeletal symptoms (23, 34%), headache (16, 24%), gastrointestinal symptoms (19, 28%) and altered sensorium (3, 4%). Co-morbidities and associations included HIV positivity (2, 3%), type 2 diabetes mellitus (13, 19%), steroid therapy (3, 4%) and HBsAg positivity (8, 12%). Ten (15%) patients had cervical lymphadenopathy, 4(6%) had splenic enlargement, 6 (7%) had hepatomegaly, 19 (28%) had hepatosplenomegaly and 2(3%) got meningeal signs. Anaemia was observed in 39 (57.3%) cases, high erythrocyte sedimentation rate (ESR) was present in 55 (80.8%) cases, leucocytosis in 10(14.7%), leucopenia in 10(14.7%), thrombocytopenia in 23 (33.82%) and thrombocytosis in 2 (2.94%) cases. Conclusions: In countries like India, where brucellosis and tuberculosis are endemic; rapid, sensitive and highly specific diagnostic methods are required to make early diagnosis and prevent resistance as there is an overlap in therapy. [Copyright &y& Elsevier]

Recently, matrix-assisted laser desorption ionization time-offlight mass spectrometry (MALDI-TOF MS) has been presented as a novel method for the direct identification of bacteria from positive blood culture bottles. The rate of the MALDI TOF MSbased identification in the present study from positive BacT/ ALERT (bioMérieux, Marcy l'Etoile, France) blood culture bottles was 30%, which is far below the previously reported sensitivities using the BACTEC (Becton Dickinson, Franklin Lakes, NJ, USA) system. We also found evidence that the Biotyper algorithm did not identify a second pathogen in cases of positive BacT/ALERT blood culture bottles containing two different species. [ABSTRACT FROM AUTHOR]

Abstract: Aims To study and compare the clinical profile, hematological features, antimicrobial susceptibility pattern of the isolates and the time to defervescence with treatment among children with culture proven enteric fever presenting at two different healthcare facilities in Mumbai. Material and Methods It is a prospective analysis of culture proven cases of enteric fever carried out at two set ups: a trust hospital providing medical care to the Mathadi workers and their families in Navi Mumbai and the other a private nursing home. The two hospitals cater to patients from two different socioeconomic strata. The Mathadi Trust hospital provides health care to potters from low socioeconomic strata while patients at the private hospital at Vashi belong to a higher socioeconomic background The above two hospital settings were selected in order to compare the characteristics of enteric fever in two different scenarios. Cases of enteric fever, diagnosed by a positive blood culture over a period of 16 months between January 2008 and April 2009 were analyzed. The clinical picture at the time of presentation, complete blood count, peripheral smear, history of typhoid immunization, results of blood culture and antimicrobial sensitivity pattern and response to treatment were recorded, compared and analysed. Results A total of 98 cases were included in the study; 42 from the trust hospital and 56 from the private nursing home. Amongst the patients from the trust hospital, 95% (40 out of 42)of the isolates were Salmonella typhi and rest (2, 5%)were Salmonella paratyphi while at the private hospital 64% (36 out of 56) were Salmonella typhi and the rest (20, 36%) were Salmonella parayphi. A or B .13 out of these 20 patients with paratyphoid were immunized against typhoid with the Vi polysaccharide vaccine. Leucocytosis with counts more than 11,000/mm3 was seen in 12% (12 out of 98) of patients. Thrombocytopenia (platelet count<1.5 lacs) was seen in 30%. None of the patients had eosinopenia. Thirty percent received antibiotics prior to blood culture sampling and in 70% of patients the cultures were obtained in the 1st week of febrile illness. The mean time to defervescence was 5 days. Conclusions Isolating salmonella from the blood of patients with enteric fever presenting as febrile illness without focus is not difficult and gives unequivocal diagnosis with antimicrobial sensitivity. The higher percentage prevalence of S. paratyphi in patients attending the private nursing home may be attributed to vaccination with Vi polysaccharide vaccine. Neutrophilic leucopenia is the norm in enteric fever but leucocytosis is also seen in patients with enteric fever. Thrombocytopenia is a common occurrence and lack of eosinopenia not uncommon.Prevalence of Nalidixic acid resistance was high. Addition of a second antibiotic did not reduce the time to defervescence. [Copyright &y& Elsevier]

Diagnosis of tubercular meningitis (TBM) is difficult in children. The GeneXpert MTB/RIF assay has been recommended by WHO in 2013 to be used in children and in extra pulmonary clinical specimens. The present study was designed to assess the diagnostic utility of GeneXpert in detecting Mycobacterium tuberculosis in cerebrospinal fluid (CSF) in TBM cases and to compare the results with liquid culture BACTEC 460. Thirty four subjects <15 y were diagnosed as TBM based on clinical, CSF and imaging details. Sensitivity of GeneXpert in CSF was 38.24 % as compared to Bactec culture which was only 14.71 % (p 0.0279). To conclude, GeneXpert MTB/RIF test is able to rapidly confirm diagnosis of TBM with higher sensitivity as compared to conventional methods and liquid culture. [ABSTRACT FROM AUTHOR]

The culture results of 4,807 blood and 383 sterile body fluid specimens received in our laboratory during a 54-month period, were analyzed to determine the time required for culture to become positive, time at which a culture could safely be considered negative, and the spectrum of isolated organisms. The specimens were processed by automated BACTEC 9120 culture system. A total of 1,677 clinically significant microorganisms were isolated. Gram positive and negative bacterial isolation rates were found to be 62.55% and 32.20%, respectively. Yeasts were recovered in 5.24%. False positivity rate was 1.5%. Clinically significant isolates recovered on day four and five were 97.81% and 99.88%, respectively. At day five, the sensitivity was 99.94% and negative predictive value 99.96%. Our data support a five-day incubation protocol for recovery of all clinically significant organisms with sensitivity reduced by 0.06%, when compared with a six-day protocol. [ABSTRACT FROM AUTHOR]

Abstract: Because of the low sensitivity of sputum smears and the delay in cultures (2–4 weeks for a result), a variety of new technologies have been developed for the more rapid and sensitive detection of PTB. This article address the new diagnostic techniques for Tuberculosis. These techniques help in early daignosis of tuberculosis. [Copyright &y& Elsevier]

Objective. Past decade has seen increase in cases of tuberculous meningitis (TBM) and multidrug resistance in such cases. The mortality rate for a mismanaged IBM is very high which increases manifold in presence of associated complicating factors. The present study was thus planned to evaluate the prevalence of MDR-TBM and look for associated complicating factors and carry Out drug sensitivity pattern in all culture positive isolates. Methods: One hundred cerebro-spinal fluid (CSF) samples from children clinically suspected of having TBM were collected and processed for detection of Mycobacterium tuberculosis by conventional methods like Ziehl-Neelsen (ZN) staining, Lowenstein- Jensen (U) culture and newer method like BACTEC 460 TB culture. Antimicrobial susceptibility was performed on all culture positive isolates by BACTEC 460 TB system. Findings: Twenty two cases could be diagnosed as definitive TBM based on BACTEC culture. Of these 22 cases, six cases (27.3%) were positive by ZN staining and/or U culture. Of all isolates tested for drug sensitivity 18 were Sensitive to all four drugs whereas 4 isolates were resistant to more than one drug. conclusion: Since the prevalence of MDR-TBM is very high we conclude that all CSF samples should be subjected to sensitivity testing to diagnose it at an early time and determine its sensitivity pattern in view of its very high mortality. [ABSTRACT FROM AUTHOR]

Summary: New drugs that can shorten tuberculosis (TB) treatment and target drug resistant strains are urgently needed. A test which could predict patients at risk of a delayed response to treatment would facilitate clinical trials of new anti-tuberculosis drugs. A widely-used test for the assessment of response to treatment is sputum smear examination. Patients who are smear positive after 2 and 3months of treatment are said to have delayed and significantly delayed treatment responses respectively. Time to positivity (TTP) values of Bactec cultures, from the first 2weeks of treatment were used to predict delayed and significantly delayed treatment responses in patients with first time pulmonary tuberculosis. Changes in TTP values early in treatment were transformed to a response ratio (r). Values of r that were less than a threshold value (r c) indicated patients who were at risk of having delayed or significantly delayed response to treatment. Accuracy of prediction was sensitive to the timing of sputum sampling and adherence to therapy in the first 2weeks. Based on TTP data from the first 2weeks of treatment, significantly delayed treatment response could be predicted with a sensitivity of 75% and a specificity of 62% while the positive (PPV) and negative predictive values (NPV) were 14% and 97% respectively. While the high NPV indicates that a large proportion of patients with a satisfactory response to treatment can be reliably identified, the low PPV value underlines the need to use TTP in conjunction with other markers of disease activity to predict unfavourable treatment response in tuberculosis treatment. [Copyright &y& Elsevier]

Objective To identify the optimum pooling rate for pooled faecal culture (PFC) as a diagnostic tool in bovine Johne's disease control, for detection of cattle shedding low concentrations of Mycobacterium avium subsp paratuberculosis ( Map). Method Thirteen target animals were selected by delayed growth of Map from initial individual radiometric faecal cultures (first growth index at 5 weeks or later). A procedure based on radiometric culture and IS900 polymerase chain reaction and restriction endonuclease analysis confirmation was then used for PFC. Results Eight samples (stored for up to 17 months at −80°C) yielded Map on subsequent culture, either from undiluted faeces or those mixed with normal cattle faeces at dilution rates from 1 in 5 to 1 in 50. From a regression equation, culture-positive animals were considered to be shedding relatively low levels of Map (< 6 × 104/g of faeces). Pooling dilutions of more than 1 in 5 reduced PFC sensitivity. A minimum incubation period of 10 weeks at a dilution of 1 in 5 is recommended to detect such infected cattle. This pooling rate in radiometric culture is probably capable of detecting cattle shedding ≤ 5 × 103 Map organisms/g of faeces, representing an estimated inoculum per culture vial of fewer than 20 viable organisms. Conclusion Map was detected in more than 50% of the stored faecal samples from cattle shedding low concentrations of the organism. A pooling rate of 5 samples per pool is required to reliably detect infected low-shedder cattle using PFC based on radiometric culture. [ABSTRACT FROM AUTHOR]

Aim: Tuberculosis remains a significant and threatening disease, particularly in developing countries. Mycobacterium tuberculosisshould be detected and identified as soon as possible to ensure the prevention of the spread of the disease. For this purpose, use of fast and reliable laboratory diagnostic methods with high sensitivity and specificity was initiated in recent years. Materials and Methods: In this study, 107 respiratory and 198 nonrespiratory (305 in total) samples submitted to Dicle University Faculty of Medicine Clinical Microbiology Laboratory were examined using the Ehrlich-Ziehl-Neelsen (EZN), BACTEC 460 TB (Becton and Dickinson Diagnostic Instrument System, Towson, MD), and MTD (Amplified Mycobacterium tuberculosis Direct Test, Gen-Probe, USA) methods. Results: In respiratory samples, sensitivity of EZN was found as 83.33%, specificity as 95.04%, positive predictive value as 50%, and negative predictive value as 98.96%, whereas in nonrespiratory samples these values were 18.18%, 98.39%, 40%, and 95.37%, respectively. In respiratory samples, sensitivity of MTD was found as 83.33%, specificity as 94.05%, positive predictive value as 45.45%, and negative predictive value as 98.95%, whereas in nonrespiratory samples these values were 54.54%, 88.23%, 21.42%, and 97.05%, respectively. Conclusions: In view of the above, the pre-diagnostic EZN test and the MTD method based on nucleic acid amplification should be applied together with the BACTEC 460 system, which is considered as a gold standard, and the evaluation should be made accordingly. Furthermore, MTD should not be used as a screening test due to its high cost, and should rather be preferred in smear-positive samples. [ABSTRACT FROM AUTHOR]

Ethanol extracts of nine lichen species, namely Everniastrum cirrhatum (Fr.) Hale ex Sipman (Parmeliaceae), Flavoparmelia caperata (L) Hale (Parmeliaceae), Heterodermia leucomela (L) Poelt (Physciaceae), Lecanora flavidorufa Hue (Lecanoraceae), Leptogium pedicellatum P.M. Jorg (Collemataceae), Lobaria isidiosa (Bory) Trevisan (Stictaceae), Rimelia reticulata (Taylor) Hale and Fletcher (Parmeliaceae), Phaeophyscia hispidula (Ach.) Essl (Physciaceae), and Stereocaulon foliolosum Nyl. (Stereocaulaceae), were evaluated for antimycobacteral properties against Mycobacterium tuberculosis H37Rv and H37Ra strains using the radiometric BACTEC method. Among the tested lichens, the virulent strain of M. tuberculosis H37Rv was found more susceptible to ethanol extract of F. caperata and H. leucomela (MIC 250 µg/mL). E. cirrhatum, R. reticulata, and S. foliolosum were found active at the concentration of 500 µg/mL. L. isidiosa, L. pedicellatum, P. hispidula, and L. flavidorufa did not exhibit activity at the maximum tested concentration of 1000 µg/mL. [ABSTRACT FROM AUTHOR]

Abstract: To compare the utility and diagnostic accuracy of BACTEC and MGIT culture systems, a total of 41 pooled faecal samples, each containing faeces from one sheep infected with the S strain of Mycobacterium paratuberculosis and four uninfected sheep was cultured. The MGIT culture system did not support the growth of the S strain of M. paratuberculosis from faeces within the time frame of the experiments, although a laboratory adapted S strain grew slowly in MGIT provided that sufficient bacteria were inoculated. In contrast, C strain grew rapidly in MGIT. The sensitivity of culture was calculated relative to the infection status of the animals, none of which had clinical signs of ovine Johne''s disease. The overall sensitivity of pooled faecal culture in the BACTEC culture system was 21.9% (95% confidence limits, 10.5–37.6), a figure dependant on the proportion of multibacillary cases. The sensitivities of the BACTEC culture system for pools containing animals with multibacillary and paucibacillary lesions were 100.0% (95% confidence limits, 47.2–100.0) and 17.8% (95% confidence limits 6.06–36.8), respectively. The contamination rate of BACTEC cultures was 9.7% compared to 14.3% for MGIT. The effect of 100μg/ml ampicillin on the S strain of the M. paratuberculosis was examined and in both BACTEC and MGIT media it delayed growth by about 1 week. The composition of MGIT medium, particularly presence of vancomycin hydrochloride, slowed the growth of the S strain. The low content of egg yolk was considered to be another possible factor. The radiometric BACTEC culture system remains the best alternative for the culture of S strain and is recommended in circumstances where the genotype (s) of the strains present in a region/farm is either unknown or S strain. [Copyright &y& Elsevier]

Abstract: We report a direct polymerase chain reaction/sequence (d-PCRS)-based method for the rapid identification of clinically significant fungi from 5 different types of commercial broth enrichment media inoculated with clinical specimens. Media including BacT/ALERT FA (BioMérieux, Marcy l''Etoile, France) (n = 87), BACTEC Plus Aerobic/F (Becton Dickinson, Microbiology Systems, Sparks, MD) (n = 16), BACTEC Peds Plus/F (Becton Dickinson) (n = 15), BACTEC Lytic/10 Anaerobic/F (Becton Dickinson) (n = 11) bottles, and BBL MGIT (Becton Dickinson) (n = 11) were inoculated with specimens from 138 patients. A universal DNA extraction method was used combining a novel pretreatment step to remove PCR inhibitors with a column-based DNA extraction kit. Target sequences in the noncoding internal transcribed spacer regions of the rRNA gene were amplified by PCR and sequenced using a rapid (24 h) automated capillary electrophoresis system. Using sequence alignment software, fungi were identified by sequence similarity with sequences derived from isolates identified by upper-level reference laboratories or isolates defined as ex-type strains. We identified Candida albicans (n = 14), Candida parapsilosis (n = 8), Candida glabrata (n = 7), Candida krusei (n = 2), Scedosporium prolificans (n = 4), and 1 each of Candida orthopsilosis, Candida dubliniensis, Candida kefyr, Candida tropicalis, Candida guilliermondii, Saccharomyces cerevisiae, Cryptococcus neoformans, Aspergillus fumigatus, Histoplasma capsulatum, and Malassezia pachydermatis by d-PCRS analysis. All d-PCRS identifications from positive broths were in agreement with the final species identification of the isolates grown from subculture. Earlier identification of fungi using d-PCRS may facilitate prompt and more appropriate antifungal therapy. [Copyright &y& Elsevier]