ABSTRACT
PURPOSE: Helicobacter pylori infection is common in the developing countries. The cagA gene is a marker of pathogenicity island (PAI) in H. pylori . The aim of this study was to determine the prevalence of cagA among dyspeptic patients in Bahrain directly from gastric biopsy and stool specimen. METHODS: A total of 100 gastric biopsy samples, 16 clinical isolates and 44 faecal specimens were collected from Bahraini adult dyspeptic patients. cagA gene of H. pylori was assessed using polymerase chain reaction (PCR). RESULTS: The cagA gene was detected in 59 (59%) from biopsy specimens, 10 (62%) clinical isolates and in 10 (22.7%) faecal specimens. The detection of cagA positive H. pylori was significantly higher in patients with duodenal ulcer (80%) compared to those with other endoscopic finding (42%) (P < 0.05). CONCLUSIONS: Using PCR to detect cagA gene directly from biopsy is a rapid and reliable technique. However, using stool specimen for genotyping in our patients showed reduced sensitivity.
Subject(s)
Adolescent , Adult , Aged , Antigens, Bacterial/genetics , Bacterial Proteins/genetics , Bahrain , Biopsy , DNA, Bacterial/isolation & purification , Feces/microbiology , Female , Helicobacter Infections/microbiology , Helicobacter pylori/genetics , Humans , Male , Middle Aged , Polymerase Chain Reaction/methods , Sensitivity and Specificity , Stomach/microbiologyABSTRACT
An essential element in the control of tuberculosis is the rapid, sensitive and specific identification of the causative agent. Until now, screening and diagnosis are largely based on clinical signs, radiological examination, tuberculin tests, sputum examination under the microscope, or culture for mycobacteria. Tuberculin tests lack specificity and only give an indication of previous exposure to mycobacteria. Direct microscopic examination of sputum is neither specific nor sensitive enough, and mycobacterial isolation is time-consuming. As an alternative to these classical methods, new nucleic acid-based technologies show promise as a more rapid, sensitive, and specific means of identification of mycobacteria. Two commercial standardized nucleic acid-based amplification techniques have been reported to yield reliable results within 5 to 7 hrs. Roche Amplicor MTB (Roche Diagnostic System, Somerville, N.J.) and Gen-Probe AMTB (Gen-Probe Inc., San Diego, Calif.). The amplified target is part of the 16S rRNA gene which is common to all the mycobacteria. An attempt has been made to describe the use of the target DNA, SenX3-RegX3, in a multiplex PCR to detect and differentiate M. tuberculosis from other mycobacteria directly from clinical specimens.
Subject(s)
DNA, Bacterial/genetics , Humans , Mycobacterium tuberculosis/classification , Polymerase Chain Reaction/methods , RNA, Ribosomal, 16S/genetics , Sensitivity and Specificity , Time Factors , Tuberculosis/diagnosisABSTRACT
Bahrain has a relatively low incidence of male urethritis; about one-half of these cases are due to N.gonorrhoeae. Despite the overall low frequency of sexually transmitted disease in Bahrain, N. gonorrhoeae isolates are often highly resistant. One-fourth of recent strains were resistant to penicillin, and 65% of the remaining isolates showed evidence of a chromosomally mediated diminished sensitivity to penicillin. Resistance to tetracycline is not yet common, but emerging chromosomal resistance and potentially poor compliance make tetracyclines inferior agents for gonorrhea therapy. We recommend ceftriaxone as primary therapy for N.gonorrhoeae in Bahrain; spectinomycin would be a reasonable second choice