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Anti-platelet factor 4 (PF4) disorders are a group of platelet-consumptive disorders characterized by platelet-activating antibodies against PF4, thrombocytopenia and an increased risk of thrombosis. PF4 is a chemokine released by platelet alpha granules upon activation, which can form immune complexes with negatively charged substances, such as heparin, cartilage components, nucleic acids, and viral and bacterial agents. Antibodies formed in response to PF4-polyanion complexes may display platelet-activating properties and cause pan-cellular activation, leading to the marked prothrombotic state of anti-PF4 disorders. In recent years, the landscape of anti-PF4 disorders has evolved to include classic heparin-induced thrombocytopenia (cHIT), autoimmune HIT (aHIT), spontaneous HIT (SpHIT), vaccine-induced immune thrombotic thrombocytopenia (VITT), and the newly recognized spontaneous VITT (SpVITT). These disorders have garnered increased attention due to their association with severe clinical outcomes. Recent discoveries have expanded the understanding of these conditions, highlighting the role of various triggers, such as upper respiratory tract infections and monoclonal gammopathy of undetermined significance, in their development. Compared to cHIT, the less common anti-PF4 disorders VITT, aHIT, SpHIT and SpVITT generally appear more severe, with aggressive disease courses, more severe thrombocytopenia and a higher frequency of bleeding, thrombosis at unusual sites, involvement of the central nervous system and of multiple vascular beds. Clinical suspicion and knowledge of the less well-known triggers of anti-PF4 disorders are pivotal to ordering the appropriate laboratory tests and initiating the necessary treatments. Herein, we will review cHIT, aHIT, SpHIT and VITT, focusing on their clinical presentation and therapeutic management.

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Background and aims. The aim of the present study was to evaluate the new chemiluminescence TGS TA system of Technogenetics (Milan, Italy) for detecting anti-Toxoplasma IgG and IgM antibodies and IgG avidity. The TGS TA system was compared with our chemiluminescence routinely used system, LIAISON XL, supplied by Diasorin (Saluggia, Italy), for the detection of IgG and IgM antibodies. Only in positive IgM samples (retrospective study) and for the IgG avidity (if existent), TGS TA system was compared to an Enzyme Linked Fluorescent Assay (ELFA) test (VIDAS, BioMérieux, Marcy-l’Étoile, France). Materials and methods. Three hundred and one sera samples, from women who came to our centre for the routine follow up pregnancy, were examined with the TGS TA system and divided in 3 groups according to IgG and IgM screening LIAISON XL tests: 106 were non-immune women (Group 1), 100 were pregnant with past infection (Group 2) and 95 were pregnant with positive or equivocal IgM (82 with positive IgG and 13 with negative IgG) (Group 3). Results. The overall concordance of the IgG results between LIAISON XL and TGS TA was 99.3%: 100% in Group 1, 98% in Group 2 and 100% in Group 3. The overall concordance of the IgM results between LIAISON XL and TGS TA was 93.9%: 100% in Group 1, 94% in Group 2 and 82.8% in Group 3. In Group 3, the concordance between the results of the IgG avidity with the ELFA and TGS TA tests was 81.7%. Comparing the clinical diagnosis obtained with our protocol and that of the TGS TA system, the overall concordance was 92.7%: 100% in Group 1, 92.0% in Group 2 and 78.9% in Group 3. Conclusions. The overall concordance of IgG antibodies is excellent for both protocols while for IgM antibodies is very high in the first group and lower in the third group, due to the presence of non-specific IgM subjects in this group. The TGS TA avidity test seems to predict ealier the maturation of the IgG compared to the ELFA test since many samples with low avidity with the ELFA were seen with moderate avidity with TGS TA and all those with borderline avidity with the ELFA were seen with high avidity with TGS TA. This system shows to be a valuable tool with overall good clinical correlation and able to clearly identify nonspecific subjects, those with a non-recent infection.

Objectives. The aim of our study was to evaluate the LIAISON® system for the detection of GDH of C. difficile by comparing the results with those obtained with the our routine EIA test, from both of unselected samples and selected samples according to the Bristol scale for stool consistency. Study Design. We examined 114 unselected stool samples (Group 1) and 104 selected samples according to the Bristol scale (type 4-7: Group 2) for the detection of GDH with enzyme immunoassay (EIA) and chemiluminescence LIAISON® system. In case of positivity for one or both tests toxins A and B were searched, with EIA, and, in case of negativity of the toxins, the test of gene amplification for the search of the locus of pathogenicity for toxins A and B was performed. Results. In Group 1, sixteen samples were positive for both tests for GDH, 93 negative for both tests, and five discordant (three EIA positive and LIAISON® negative; two EIA negative and LIAISON® positive): total concordance between the two methods: 95.6%. Of the five discordant samples, all were toxin A & B negative, of these only one was positive to molecular biology. In Group 2, fifteen samples were positive for both tests for GDH, 89 negative for both tests and no discordant: total concordance between the two methods: 100%. Conclusions. Our data indicate a perfect correlation between LIAISON® and EIA, when samples are chosen according to stool consistency at least grade 4 of the Bristol scale.The possibility to use an automatic and fast system, like LIAISON®, also allows an optimization of workflows.

We evaluated the correlation among four commercial ELISA tests for the presence of anti-Mycoplasma pneumoniae IgM antibodies in 36 samples obtained from patients with respiratory infections.The overall concordance among the four tests was 30%, while the one among single tests varies from 39% to 75%. Given the variability of the results, it is necessary to implement a External Quality Control specific for anti-Mycoplasma pneumoniae IgM antibodies.

Chlamydia trachomatis (C.t.) infection is one of the most prevalent sexually transmitted disease in Europe and in developed countries. The main biological features and pathogenic mechanisms of C.t. infection are summarized in this review. It usually occurs without symptoms and often goes undiagnosed. If untreated, it can cause severe consequences for women, including pelvic inflammatory disease (PID), ectopic pregnancy and tubal infertility. Several studies have found that Chlamydia is more common among young women

The introduction of new diagnostic instruments in the Microbiology Laboratory imposes a trial period which must precede introduction in the routine. This period is aimed to minimize any organizational difficulty and/or staff distress. In this context, we suggest an organizational model that can quickly evaluate accuracy, repeatability and carry over of new diagnostic instruments.

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Background: A recent World Health Organization survey estimated about 10.4 million new tuberculosis (TB) cases per year with a high mortality rate. A rapid and accurate diagnosis of TB is very important for the optimal treatment and the prevention of spread. In the last few years rapid nucleic acid amplification tests for the detection of Mycobacterium tuberculosis complex (MTB) were developed. Materials and methods: In this study we have compared TRCReady MTB, based on the Transcription Reverse Transcription Concerted Reaction technology (TRC) and MTB ELITe MGB Kit, a qualitative nucleic acid amplification assay, for the direct detection of MTB in 56 respiratory and 24 non-respiratory specimens, collected from September to November 2015. Results: Both methods did not detect any MTB in 45 respiratory samples and in 22 non-respiratory specimens with negative cultures. MTB ELITe MGB Kit identified MTB in 8 respiratory samples with MTB positive cultures, 7 of which were detected by TRCReady MTB as well. Two non-respiratory MTB positive cultures were correctly identified by both methods. In two respiratory samples with Mycobacterium Other Than Tuberculosis positive cultures both methods provided negative results. Conclusions: In conclusion, TRCReady MTB performance proved comparable to that of MTB ELITe MGB Kit in the diagnosis of pulmonary and extra-pulmonary TB, with a shorter analytical time (50 vs 110 min).

An unexplainable error that occurred in the normal laboratory routine is described: a positive result for the anti-HCV antibodies detection was found in a single blood tube collected from a patient, while the other samples taken simultaneously were anti- HCV negative. After the first checks that did not highlight any special problems, an internal committee composed of the chiefs of the units involved was established. This committee, using investigative analysis with the Root Causes Analyses model was able to understand the error.

Background and aims: The aim of the present study was to evaluate the new Technogenetics TGS TA system for detecting antirubella IgG and IgM antibodies and IgG avidity. TGS TA system was compared with our routinely used system, LIAISON XL, for the detection of IgG and IgM antibodies. Only in positive IgM samples (retrospective study), TGS TA system was compared to an ELFA IgM test and with an ELISA test for the IgG avidity (if existent).Materials and methods: Two hundred and seventy six sera samples from women were examined with TGS TA system and divided in 3 groups according to IgG and IgM screening LIAISON XL tests: 112 were of childbearing age and non-immune women (Group 1), 106 were pregnant with past infection or vaccinated (Group 2) and 49 were pregnant with positive or equivocal IgM (Group 3). Results: The overall concordance of the IgG results between LIAISON XL and TGS TA was 93.3%: 86.6% in Group 1, 97.2% in Group 2 and 100% in Group 3. The overall concordance of the IgM results between LIAISON XL and TGS TA was 89.0%: 100% in Group 1, 100% in Group 2 and 35.6% in Group 3. In Group 3, the concordance between the results of the IgG avidity with the ELISA and TGS TA tests was 85.7%. Comparing the clinical diagnosis obtained with our protocol and that of the TGS TA system, the overall concordance was 97.4%: 86.6% in Group 1, 97.2% in Group 2 and 85.7% in Group 3. Conclusions: TGA TS system shows to be a valuable tool with overall good clinical correlation and able to clearly identify nonspecific subjects, those with a non-recent infection or those who are vaccinated. The TGS TA test also seems to be especially sensitive in indicating vaccinated subjects with low IgG levels as immune.

Background and aims: The aim of the present study was to evaluate the new Technogenetics TGS TA system for detecting anti-Cytomegalovirus IgG and IgM antibodies and IgG avidity. The TGS TA system was compared with our routinely used system, LIAISON XL, for the detection of IgG and IgM antibodies. Only in positive IgM samples, TGS TA system was compared to an enzyme linked fluorescent assay (ELFA) test (VIDAS, BioMérieux, Marcy-l’Étoile, France) and with LIAISON XL system for the IgG avidity (if possible). Materials and methods: Three hundred sera samples from pregnant women were examined with the TGS TA system and divided in 3 groups according to IgG and IgM screening LIAISON XL tests: 102 were non-immune women (Group 1), 98 were pregnant with past infection (Group 2) and 100 were pregnant with positive or equivocal IgM (95 with positive IgG and 5 with negative IgG) (Group 3). Results: The overall concordance of the IgG results between LIAISON XL and TGS TA was 98.3%: 97.1% in Group 1, 100% in Group 2 and 98.0% in Group 3. The overall concordance of the IgM results between LIAISON XL and TGS TA was 92.1%: 100% in Group 1, 99.0% in Group 2 and 70.1% in Group 3. In Group 3, the concordance between the results of the IgG avidity with the LIAISON XL and TGS TA tests was 87.4%. Comparing the clinical diagnosis obtained with our protocol and that of the TGS TA system, the overall concordance was 94.3%: 97.1% in Group 1, 99.0% in Group 2 and 87.0% in Group 3. Conclusions: In conclusion, the overall clinical concordance between the LIAISON XL/VIDAS protocol and the TGS TA system is excellent. TGA TA system shows to be a valuable tool able to clearly identify non-specific subjects, those with a non-recent infection and classify as either recent or past infection half of the subjects with undetermined infection with our protocol.

Background and aims: Blood culture (BC) results are essential to guide antimicrobial chemotherapy for patients with sepsis. However, BC is a time-consuming exam, which can take several days. Reducing BCs turn around time (TAT) could impact on multiple outcome parameters and TAT monitoring is an important tool for measurement of microbiology laboratory performance. The aim of this study was to provide an overview of BC TATs among Italian microbiology laboratories. Materials and methods: Five laboratories collected and recorded, for a month period, date and time of the BC processing events. Cumulative TATs were analysed using the GraphPad software. Results: Participating laboratories reported data from 302 sepsis episodes. The median time from when the BC system produced a positive signal until Gram-stain results were reported was 7.6 hours. A rapid molecular identification and antimicrobial susceptibility testing (AST) was performed in 26.5% of BCs. Mean TAT for identification report was significantly lower when a molecular approach was adopted (12 vs. 28.7 hours, PConclusions: BC is a time-consuming exam, however, molecular identification and AST methods can drastically reduce time to results. The lack of difference between TATs observed for laboratories working 7 days/week and 6 days/week, coupled with a high rate of BCs turning positive during the night enable to conclude that the most urgent measure to reduce TATs is the expansion of laboratory regular duty hours.

Serological tests for antibodies against specific EBV antigens are commonly used to define the state of the infection as well as for differential diagnosis with the other agents responsible for mononucleosis syndrome.The use of only three parameters (VCA IgG and IgM and IgG EBNA-1) is normally enough to distinguish acute and past infection in immunocompetent patients: the presence of VCA IgG and IgM without EBNA-1 IgG indicates acute infection, whereas the presence of VCA IgG and EBNA-1 IgG without VCA IgM is typical of past infection. These profiles (beyond the negative profile for all three markers indicating the absence of infection) cover the vast majority of situations that can be found in the routine laboratory. In a minority of cases, however, the serological pattern may sometimes be difficult to interpret: presence of VCA IgG without either VCA IgM or EBNA-1 IgG, simultaneous presence of VCA IgG,VCA IgM and EBNA-1 IgG, presence of EBNA-1 IgG without either VCA IgM or VCA-1 IgG. In order to interpret these serological patterns correctly, it is necessary to use other laboratory tests: VCA IgG avidity, immunoblotting for EBV IgG and IgMV, or a search for heterophile antibodies, anti-EA antibodies or viral genome by means of gene amplification techniques.

Pseudomonas aeruginosa has emerged as a major opportunistic pathogen causing catheter-associated urinary tract infections (CA-UTIs) associated with high mortality and morbidity. In this study 18 P. aeruginosa isolates from urine of catheterized patients were evaluated for in vitro biofilm formation.All the tested strains showed the ability to form biofilm more thicker than those formed by a cohort of 29 blood culture strains belonging to the same species. Photodynamic antimicrobial chemotherapy (PACT) is a novel antimicrobial treatment that exploits a photosensitizer (PS) and visible light to induce lethal oxidative damages in bacterial cells and could be used as local antimicrobial approach in CA-UTIs. Here we tested the susceptibility of planktonic and sessile cultures of P. aeruginosa strains, the model strain PAO1 and CA-UTI isolates, to photodynamic inactivation with a di cationic porphyrinic photosensitizer, the 5, 15-di (N-benzyl-4-pyridynium)-porphyrin di chloride.Although Pseudomonas aeruginosa is regarded as a difficult target for antimicrobial chemotherapy, satisfactory bactericidal activities on both planktonic and biofilm cultures were observed.

The dry leaves of two African plants of the Combretaceae family, furnished by the botanist of the St. Jean de Dieu hospital of Tangueità (Benin, central Africa),were extracted with a sequence of 5 solvents with increasing polarity (from cyclohexane to water).The raw materials, obtained from these extractions following solvent evaporations, were tested for antibiotic activity against gram negative and gram positive bacterial strains. According to the results of a modified Kirby-Bauer test, no promising effect was obtained against Gram negative bacteria while interesting dose-effect activities were observed against Gram positive strains. In particular, from G. senegalensis active compounds were found in the low polarity extract (dichloromethane) which, at a concentration of 800 μg/disk (13 mm diameter disk), resulted in a grow inhibition crown of 4.7 mm and 2.6 mm on Enterococcus faecalis and Staphylococcus aureus MSSA, respectively. An higher amount of the aqueous extract (4760 μg/disk) also produced a good result as 5.7 mm and 5.0 mm crowns were observed. The extracts from C. micranthum showed an inhibiting effect in the more polar extracts (i.e. from ethanol and water) which gave 1 mm of grow inhibition crown on both strains at a concentration of 1000 μg/disk. The most promising extract from each plant was partially purified and then tested on some clinical relevant bacterial strains: S. aureus MRSA, Clostridium difficile, Streptococcus pyogenes, Streptococcus pneumoniae, Corynebacterium striatum, Neisseria gonorrhoeae, Haemophylus influenzae, Escherichia coli, obtaining a good killing effects on the Gram positive bacteria of the panel.

Background. The IgG avidity test is usually used for differentiating between primary and non-primary HCMV infection within 3 months. Weak avidity is highly suggestive of a primary infection, while high avidity tends to exclude it.An indeterminate or moderate avidity, however, does not allow a clear dating. Since there are several avidity tests with different performances, those tests that are able to minimize the results with indeterminate/moderate avidity are particularly useful. Objectives. The aim of our work was to evaluate the results obtained with two IgG avidity tests in IgG and IgM anti-HCMV positive patients. Study Design. 113 anti-HCMV IgG and IgM positive samples were tested with Enzime Linked Fluorescent Assay (ELFA) and Chemiluminescence Immuno Assay (CLIA) IgG avidity test. Results. 21 samples (18.6%), 50 (44.2%) and 42 (37.2%) with ELFA and 53 samples (46.9%), 10 (8.8%) and 50 (44.2%) with CLIA were found to have respectively low, indeterminate/moderate and high avidity. Of the 50 ELFA indeterminate avidity samples, 32 (64%), 10 (20%) and 8 (16%) were found to have respectively low, moderate and high CLIA.avidity. For 11 cases of the 32 ELFA indeterminate avidity and CLIA low avidity, there were previous data showing a seroconversion within three months. In a case of the 8 ELFA indeterminate avidity and CLIA high avidity, there were, instead, previous data of IgG and IgM positivity already four months earlier. Conclusions. It appears that the CLIA test for IgG avidity is more effective than ELFA for dating HCMV infection.

The ELISA screening detection of anti-EBNA-1 IgG in the absence of VCA IgG and IgM is rare but may lead to doubts in interpretation.We used immunoblotting to characterise 23 serum samples with “isolated EBNA-1 IgG” upon ELISA screening, and found that all showed VCA anti-p23 and 13 (56.6%) also showed VCA anti-p18 antibodies. It therefore seems impossible for a sample to show anti-EBNA-1 IgG without anti-VCA IgG antibodies. Furthermore, although anti-p18 antibodies are thought to develop later and therefore considered to be markers of past infection, about 1% of all previously infected EBNA-1 IgG-positive patients do not have them.

The aim of our study was to evaluate the performance of screening for toxoplasmosis in pregnancy through comparing the data obtained from Italian and foreign women. 3074 women, 2465 Italians (80.2%) and 609 foreigners (19.8%) had undergone screening for serological detection of anti-Toxoplasma IgG and IgM antibodies in the years 2005-2007. 85.0% of the Italian women and 84.1% of the foreign women had the first blood test in the first trimester of pregnancy (difference not statistically significant).Among anti-Toxoplasma negative women average of blood tests during pregnancy was 3.69 for the Italians and 3.42 for the foreigners (p

Introduction. Anti-Toxoplasma antibodies prevalence varies worldwide, showing to be lower in industrializes countries of Northern Europe, and higher in developing countries. In Europe from the 80s’ to 2000 a progressive lessening of the prevalence within different ages was observed. Aim of our survey is to analyze the prevalence of anti-Toxoplasma antibodies among Italian and foreign women afferent to Legnano Hospital from 2000 till 2005. Method. The IgG antibody level of anti-Toxoplasma was tested in 11246 women, aged between 15 and 44 years, 1230 of which (10.9%) were foreigners. Results. The prevalence of IgG anti-Toxoplasma decreased from the 31.2% in 2000 to the 21.4,% in the 2005 (P