மருத்துவ நுண்ணுயிரியல் & நோய் கண்டறிதல்

Since 2007 the Netherlands has been faced with serious public health issues resulting from an epidemic outbreak of Q-fever. Although acute Q-fever may etiologically be linked to Coxiella burnetii, there is currently no expert consensus on the primary cause of the pathogenic clinical manifestation in patients suffering from Q-fever fatigue syndrome (QFS). Scientists have been searching for the cause of QFS for many years. In the Netherlands, negative qPCR results and serology tests have led to the conclusion that there were no viable C. burnetii present in patients suffering from the Q-fever fatigue syndrome. In another study, infecting test animals with bacterial remnants taken from QFS patients did not result in a transfer of infection. The conclusion is that no viable bacteria are present and that the clinical condition should be attributed to an immuno-modulatory complex (IMC).

The QFS subjects in this study had been previously serologically diagnosed as having Q-fever. Using Fluorescence in situ Hybridization technology, the authors have found that QFS significantly correlated with the presence of viable large, cell variants (LCV) of C. burnetii. Other studies have shown that the host cells for these LCVs are macrophages, the part of the immune system designed to ingest and destroy pathogens. The cell wall of an LCV has a very limited amount of peptidoglycan and is, in fact, a cell wall deficient bacteria (CWDB). These CWDB hosted in the macrophages can multiply within the lysosome, and eventually revert back to the classical bacterial form given the right conditions.

This article demonstrates that automated Fluorescence in situ Hybridization technology can be used as a method to determine the presence of bacterial DNA of viable L-form bacteria in white blood cells derived from patients suffering from Q-fever Fatigue Syndrome.

Urinary tract infection (UTI) is a common bacterial infection known to affect different parts of the urinary tract of both male and female. Escherichia coli have been found to be responsible for causing 80% to 90% of the infection. An investigation was carried out to determine the prevalence of bacteria, especially E. coli implicated in UTI, and to ascertain their antibiotics susceptibility pattern. Early morning mid-stream urine samples were collected from 250 patients aged 18 to 60 years, between March and July of 2016 from 5 major Hospitals in the study location. The isolates were identified using standard microbiological methods and susceptibility tests were carried out using ten antibiotics. Results Showed that 65 (30.7%) of the isolates were E. coli. Pseudomonas aeruginosa 45 (21.2%), Klebsiella pneumoniae 42 (19.8%), Staphylococcus aureus 32 (15.1%) and Proteus mirabilis 28 (13.2%). The percentages of resistance of E. coli isolates to antimicrobial agents were chloramphenicol (64.9%), sparfloxacin (59.5%), ciprofloxacin (73.0%), septrin (73.0%), amoxacillin (91.9%), augmentin (83.8%), gentamycin (48.7%), perfloxacin (40.5%), ofloxacin (40.5%) and streptomycin (54.1%). The need for constant antimicrobial susceptibility surveillance by health managements system that will help clinicians to provide safe and effective therapy is advocated.

Background: Influenza virus is a significant public health problem throughout the world. Increased insight into the basic biology of the virus may enable the development of more effective anti-influenza preventives and therapeutics.

Methodology: The occurrence of specific amino acid subsequences in H1N1 and H3N2 influenza virus hemagglutinins was used for joint detection of those subsequences in human proteins. Only subsequences consisting of at least 5 contiguous amino acids were considered for further study.

Results: Ten H1N1 hemagglutinin amino acid subsequences and nine H3N2 hemagglutinin amino subsequences were identified as also occurring in proteins of human origin. The length of the subsequences selected for further study, ranged from 5 contiguous amino acids to 8 contiguous amino acids.

Conclusion: The joint occurrence of amino acid subsequences in influenza hemagglutinins and in human proteins may help explain the relatively low efficacy of current anti-influenza vaccines. It is proposed that the identification of the joint subsequences may be useful for the improved design of anti-influenza therapeutics and especially anti-influenza vaccines.

Aim: To evaluate the performance of brain heart infusion (BHI) versus Todd-Hewitt (TH) media for the culture and identification of Group B Streptococcus (GBS) in vaginal swabs from pregnant women in last trimester. Two enrichment broth media were compared in terms of sensitivity, accuracy and cost.

Methodology: 242 vaginal samples collected during March and May 2018 from Tam Anh hospital were included in this study. Each sample was collected in duplicated swabs, each swab was then cultured in BHI and TH broth and following the same method in accordance with the manufacturers’ guidelines.

Results: BHI had excellent diagnostic performance compared to TH, with sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 91.30%, 100%, 100%, 98.00% and 98.35%, respectively. BHI decreased material and supply costs 88.31%.

Conclusion: BHI was chosen for introduction into routine use, due to its better sensitivity and accuracy, meanwhile lower cost than TH.

Background: Kodamaea ohmeri or Pichia ohmeri is relatively rare yeast that belongs to ascomycete group and Saccharomycetaceae family. It is recognized as an important pathogenic fungus in immunocompromised hosts.

Methodology: Herein, we describe three cases where Kodamaea ohmeri was isolated in peripheral samples: nasal in one case and auricular in two cases. The identification was carried out by Vitek®2 YST ID card and confirmed by PCR sequencing. Susceptibility to antifungal was made by E-test.

Results: These yeasts were identified K. ohmeri using phenotypic, biochemical and molecular methods. All isolates were susceptible for voriconazole and amphotericin B, resistant for caspofungin and susceptible-dose-dependent for Fluconazole.

Conclusion: These are firsts cases reported in Tunisia which incites to pay more attention to the emergence of this yeast in human pathology since more it develops resistances to antifungals.