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Objectives: To evaluate the epidemiology of clostridioides difficile infections and colonisation in a tertiary-care setting., Methods: The cross-sectional study was conducted at the Combined Military Hospital, Rawalpindi, Pakistan, from June 1, 2017, to October 31, 2019, and comprised adult patients admitted in high-risk units of the hospital for any disease experiencing watery stools after 48 hours of hospital admission and passing more than 3 stools per day with no other recognised aetiology. Stool samples of the participants, diagnosed with antibiotic associated diarrhoea, were submitted for glutamate dehydrogenase antigen assay and clostridioides toxin A/B assay detected by enzyme-linked immunosorbent assay and clostridioides difficile toxin gene detection by polymerase chain reaction. Clostridium difficile-associated diarrhoea was diagnosed by a positive toxin assay or polymerase chain reaction. Data was analysed using SPSS25., Results: Of the 715 subjects, 322(45%) were males and 393(55%) were females. The overall mean age was 56.64±8.57 years, and 488(68.3%) were aged <60 years, while 227(31.7%) were aged >60 years. The incidence of clostridioides difficile-associated diarrhoea was found in 10(1.4%) patients and was highest in oncology unit 3(4.3%). No positive case was detected from the high dependency unit and the surgical ward. All the10(1.4%) positive cases were on >2 antibiotics with a combination of oral vancomycin and intravenous metronidazole. Mortality rate was significantly higher in the positive cases compared to those with clostridioides difficile colonisation (p<0.05)., Conclusions: The incidence of clostridioides difficile-associated diarrhoea was found to be low.

Objective: To compare the efficacy of Gene Xpert mycobacterium tuberculosis-rifampicin and multiplex polymerase chain reacton for the detection of mycobacterium tuberculosis and Rifampicin resistance., Methods: The cross-sectional validation study was conducted at the Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi, Pakistan, from March to October 2018, and comprised mycobacterium tuberculosis-positive rifampicin-resistant and rifampicin-susceptible samples, with the latter acting as negative controls. Gene Xpert mycobacterium tuberculosis-rifampicin assasy and multiplex polymerase chain reacton were applied simultaneously and compared with gold standard mycobacterium growth indicator tube 960. Data was analysed using SPSS 24., Results: Of the 192 samples, 84(44%) were culture-positive rifampicin-resistant and 108(56%) were culture-positive rifampicin-susceptible. Overall, 84(44%) were found positive. Gene Xpert mycobacterium tuberculosis-rifampicin assay detected all 84(100%) rifampicin-resistant samples, while multiplex polymerase chain reacton detected 44(52.3%) such samples. Sensitivity, specificity, positive predictive value and negative predictive value of Gene Xpert were 100% each respectively, while the corresponding values for multiplex polymerase chain reacton were 52%, 100%, 100% and 72% respectively., Conclusions: Molecular detection of mycobacterium tuberculosis and resistance by Gene Xpert and multiplex polymerase chain reacton simultaneously was found to be a rapid and cost-effective method.

Objective: To assess the utility of galactomannan and beta-D-glucan assays in the diagnosis of invasive aspergillosis in clinically suspected cases, and to compare their diagnostic potential to determine whether a combination of the two may result in an early and specific diagnosis., Methods: The descriptive cross-sectional case-control study was conducted at the Armed Forces Institute of Pathology, Rawalpindi, Pakistan, from April 1, 2017, to March 31, 2018, and comprised serum samples from clinically suspected invasive aspergillosis patients and healthy controls. The sera were tested for galactomannan and beta-D-glucan detection. Proven, probable and possible categories of invasive aspergillosis according to European Organisation for Research and Treatment of Cancer / Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group criteria. Galactomannan antigen was detected using a one-stage immunoenzymatic sandwich microplate assay. Beta-D-Glucan antigen was detected using a protease zymogen-based colorimetric assay. Sensitivity and positive / negative likelihood ratio of both the cases and the controls were calculated and compared., Results: Of the 178 subjects, 119(67%) were cases and 59(33%) were controls. Beta-D-glucan assay was more sensitive than galactomannan assay (91.6% versus 80.67%) whereas galactomannan assay was more specific than beta-D-glucan assay (86.44% versus 76.27%) in the diagnosis of invasive aspergillosis. The sensitivities of both assays decreased with decreasing probability of invasive aspergillosis, i.e., maximum sensitivities of both beta-D-glucan and galactomannan assays were for proven cases (100% versus 87.5%), followed by probable cases (89.29% versus 85.71%), and possible cases (91.57% versus 78.31%)., Conclusions: Both beta-D-glucan and galactomannan assays seemed to play an encouraging role in the diagnosis of invasive aspergillosis in high-risk clinically suspected cases, with the former assay being more sensitive and the latter assay being more specific.

Objective: To evaluate a direct antibiotic susceptibility testing method for blood culture.., Methods: The cross-sectional comparative study was conducted at the Armed Forces Institute of Pathology, Rawalpindi, Pakistan, from December 2016 to October 2017. Direct antimicrobial susceptibility testing was performed from positive blood culture bottles. Bacterial identification was done by using API 10S. Different antimicrobial panels were employed for Gram-negative rods (GNRs), gram-positive cocci (like suspected Staphylococci and Enterococci). Results were compared with conventional disk diffusion testing and very major, major and minor errors were calculated. Result agreement and kappa coefficient scores were generated for categorical agreement. SPSS 24 was used for data analysis., Results: Of the 101 bacterial isolates, 82(81.2%) were Gram negative rods and 19(18.8%) were Grampositive cocci. Among 781 bacteria-antibiotic comparisons, the number of very major errors was 3(0.4%), major errors were 7(0.9%) and minor errors were 12(1.5%), while, 759(97.2%) comparisons yielded the same results. The kappa coefficient was 0.946, showing almost perfect agreement. Direct identification of Gram negative rods was successful in 53(64.6%) cases., Conclusions: Direct susceptibility testing of blood culture produced reliable results for majority of the antimicrobials.

Objective: To determine the pattern of blood stream infections and their antibiotic susceptibility profile with infectivity predictors in a neonatal setting., Methods: The descriptive cross-sectional study was conducted at the Armed Forces Institute of Pathology, Rawalpindi, Pakistan, from December 1, 2016,to April 30, 2018, and comprised blood culture samples received in Bactec/BactAlert paediatric bottles from neonates aged 0-30 days admitted in the neonatal intensive care unit. The samples were processed as per the standard guidelines. Antibiotic susceptibility was checked as per guidelines of the Clinical and Laboratory Institute. VITEK 2 system was used for rapid identification and minimum inhibitory concentrations of the drugs. SPSS 24 was used for data analysis., Results: Out of 640 samples, 172(27%) were culture-positive. Among them, 98(57%) were gramnegative rods, 50(29%) gram-positive cocci and 24(14%) were fungi. Of the 172 pathogens identified, Klebsiella pneumoniae was 39(22.7%) followed by Candida species 24(14%) and methicillin-resistant Coagulase-negative staphylococci 20(11.6%). Of Klebsiella pneumoniae isolates, 26(58%) were extended spectrum -lactamase producers. Among Acinetobacterbaumanii, 11(58%) were extensively drug resistant and Carbapenem-resistant strains were 20(91%). Also, 4(8%) isolates of Enterococcus faecium were vancomycin-resistant., Conclusions: Majority of the isolates causing blood stream infections in neonatal intensive care unit were multi drug resistant, posing a therapeutic challenge for the neo natologists .

A 61 year male, admitted in Combined Military Hospital Rawlpindi on 12th March 2017, operated for diverticulitis became colonized with Staphylococcus haemolyticus. Patient suffered repeated septic episodes caused by the same organism during his stay in hospital. The strain was identified as methicillin resistant Staphylococcus haemolyticus (MRSH) also resistant to Linezolid by analytical profile index for Staphylococcus (API Staph) and VITEK 2 Gram positive cocci panel. The isolate was cultured from blood cultures, Central Venous Catheter (CVC) tip and skin swabs. Patient was successfully treated with injectable vancomycin and skin decolonization was acheived with chlorhexidine bath after which no episode of MRSH infection occurred. Patient had an uneventful recovery and was discharged on 21st June. His follow up visit showed clinical improvement.