Association of CagA and VacA genotypes of helicobacter pylori with gastroduodenal diseases

Helicobacter pylori [H. pylori] infects the majority of the population in developing countries. However, the rate of gastrointestinal complications has no parallel with the infection. In the present study our aim was to detect and type the cagA [cytotoxin associated gene] status and the vacA [vacuolating cytotoxin] genotypes directly from biopsy DNA, and to further define the relationship between H. pylori genotypes and gastroduodenal pathology. Antral gastric biopsies were obtained for molecular analysis and histopathological diagnosis from 105 patients with dyspeptic symptoms undergoing upper gastrointestinal endoscopy. H. pylori DNA, cagA status and vacA s and m types were detected by polymerase chain reaction [PCR]. H. pylori DNA was detected in 100 [95.2%] of gastric biopsy specimens, of those, 43 [43%] were cagA positive and all [100%] were vacA positive. The vacA s2/m2 genotype was the most prevalent [54%] followed by s1/m2 [27%], then s1/m1 [16%] and 3% showed multiple genotypes. We found 90.5% and 75% of cases with peptic ulcer disease [PUD] and gastric adenocarcinoma respectively to be cagA positive in contrast to only 28% of gastritis cases. The vacA s1 allele was the commonest in PUD and gastric adenocarcinoma cases [85.7% and 75% respectively], while the vacA s2 allele was the commonest in gastritis cases [70.7%]. In conclusion, we suggest the possibility of a genotype-phenotype association of H. pylori disease. Determination of cagA status and vacA genotypes may contribute to the potential clinical identification of patients at different levels of risk. We recommend further studies involving other virulence genes

Evaluation of prognostic value of adhesion molecules in septic critically Ill patients

Septic shock is the most frequent cause of death in intensive care units. Despite major advances in antimicrobial therapy, critical care and surgical techniques, there has been little improvement in morbidity or mortality due to sepsis or septic shock. The aim of this study was to evaluate the role of vascular cell adhesion molecule-1 [VCAM-1] and intercellular adhesion molecule-1 [ICAM-1] in sepsis, septic shock, haemodynamic changes and outcome. Thirty intensive care unit patients suffering from sepsis with or without shock were subjected to blood culture, culture from the site of infection if possible, blood gases analysis, acute physiology and chronic health evaluation score [APACHE II] at baseline, multiple organ failure score on day one [MOF1], cummulative organ failure score [MOFC] on day 5, haemodynamic measurements, as well as serum VCAM-1 and ICAM-1 levels for 5 days after admission. Ten healthy control subjects were also included in the study. The most common site of infection was the chest, the isolates were mostly Gram negative [60%of cases], 9 patients [30%] had positive blood cultures. Serum ICAM-1 and VCAM-1 levels gradually increased from a baseline till day 5 of the study and were significantly higher in patients on admission [62 +/- 20.21, 404.67 +/- 130.85 ng/ml, respectively] than in the control group [14.0 +/- 4.71, 128.0 +/- 34.9 ng/ml respectively], [P=0.00]. They were higher in shocked than in non-shocked patients, and significantly so in non-survivors than in survivors and in patients with positive blood cultures than in those with negative blood cultures, throughout the study period [P=0.00]. A significant positive correlation was observed between serum ICAM-1 and VCAM-1 levels on one hand, and APACHE II as well as both organ failure scores for the 1st day or cumulative on the other hand. We conclude that these adhesion molecules could be measured in critically ill septic patients to predict prognosis and guide therapy

Detection of enteroviral RNA in cerebrospinal fluid [CSF] specimens of children presenting with aseptic meningitis using reverse transcription- polymerase chain reaction [RT-PCR]: correlation with CSF cell counts and elevated protein levels

Enteroviruses are known to be involved in at least 85% of cases of aseptic meningitis [AM] for which an aetiology can be determined, particularly among children and infants. The diagnosis of enteroviral meningitis presents a challenge for the clinician and is frequently a diagnosis of exclusion as clinical criteria alone are not enough to distinguish between enteroviral AM and other, more serious, central nervous system [CNS] infections caused by other neurotropic viruses and some bacteria. This has raised concerns regarding accuracy of diagnosis and its impact on patient management. The aim of this study was to determine whether cerebrospinal fluid [CSF] parameters mainly pleocytosis and elevated protein level can be used to establish viral aetiology of meningitis and to indicate if Enteroviral Reverse Transcription- Polymerase Chain Reaction [EV RT-PCR] should be performed. The material of this study consisted of 50 CSF specimens obtained by lumbar puncture from children presenting with clinical features of meningitis, and with no Gram stain or culture evidence of bacterial or fungal infection who were admitted to El Shatby University Paediatrics Hospital in Alexandria, throughout a period of approximately 6 months starting from April 2005. CSF samples were used to perform laboratory analysis including cell count, differential leucocyte count, protein level, and for detection of enteroviral RNA by EV RTPCR using general primers selected in the highly conserved 5' non-coding region. Twenty four percent of samples tested positive for EV RNA by EV RT-PCR. Pleocytosis was detected in 54% of the studied samples with lymphocyte predominance in 63% of them. Lack of CSF pleocytosis in CSF samples that were positive for EV RNA was limited to one case below 2 months of age. For all ages, the sensitivity, specificity, positive predictive value [PPV], and negative predictive value [NPV] of presence of pleocytosis in relation to the results of RT-PCR were: 92%, 58%, 41% and 96% respectively. They dropped to 67%, 50%, 33% and 80% respectively in the age group 2 months and were 100%, 60%, 43% and 100% respectively in the >2 months age group. Elevated CSF protein level was found in 58.3% of EV RT-PCR positive cases and 58% of EV RT-PCR negative cases. For all ages, the sensitivity, specificity, PPV, and NPV of elevated protein levels in relation to the results of RT-PCR were 58%, 42%, 24%, and 76%, respectively. When we examined a combination of CSF parameters: the presence of both pleocytosis and elevated protein level, in relation to EV RT-PCR results, the sensitivity, specificity, PPV, and NPV were 58%, 74%, 41%, and 85% respectively. We conclude that CSF parameters namely pleocytosis and elevated protein level are not satisfactory to establish viral aetiology of meningitis even when used in combination. We recommend the introduction of EV RT-PCR as a simple, rapid and reliable routine test to establish enteroviral diagnosis in the early course of meningitis to eliminate unnecessary treatment with parenteral antibiotics until a bacterial cause can be disproved, and shorten hospitalization periods