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Copyright of African Journal of Clinical & Experimental Microbiology is the property of African Journals Online (AJOL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Helicobacter pylori has been associated with chronic diarrhoea, iron deficiency anaemia, growth retardation, gastric malignancies, peptic ulcer disease, and gastritis among children. Diagnosis of this infection has been invasive using biopsies while stool culture is not common or routinely practiced. This study was designed to detect and isolate H.pylori from stool of diarrhoeic children and highlight possible use of such for routine laboratory diagnosis of H.pylori infections. Material and methods: Two hundred and sixty faecal samples obtained from diarrhoeic children were screened for H. pylori antigen, using H. pylori stool antigen test kit (HpSA) and cultured on modified DENTS medium. Cholestyramine and nitrobluetetrazolium salt were added to the stool and the medium respectively to aid isolation of H. pylori. Correlation of BMI and H. pylori infection of the children was also evaluated. Results: Twenty-six (10%) samples showed growth on culture while 91 (35%) tested positive for H. pylori antigen. Of the 26 children with positive culture, 16 had a low BMI. HpSA has sensitivity and specificity of 11.5% and 62.4%. There was a significant association (χ2 = 12.86, df=2, P-value = 0.004) between age group of participants and use of HpSA kit. Conclusion: Stool culture for recovery of H. pylori is feasible in our environment and diarrhoeic children should be screened for H. pylori using both HpSA and culture. H. pylori is suggested to be screened routinely especially among children having diarrhoea and are underweight. Albeit, other causes should be eliminated before concluding on the reason for the underweight. [ABSTRACT FROM AUTHOR]

Copyright of West Indian Medical Journal is the property of West Indian Medical Journal (WIMJ) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Slums are a wide range of low-income settlements with poor living conditions. The quality of the dwellings varies from simple shacks to permanent structures, while access to water, electricity, sanitation and other basic services and infrastructure tends to be limited. Noncommunicable diseases (NCDs) exist in slums as the inhabitants adopt an urbanised lifestyle which places them at high risk. Lack of knowledge about the complications of NCDs and how to control them contributes to a large percentage of undetected and untreated cases. Therefore, our recently concluded study aimed to reduce the prevalence of NCDs by promoting a healthy lifestyle in three Nigerian urban slums using a community-engaged research approach. We decided to adopt this approach since community-engaged research takes place in real-world conditions, thus increasing the applicability of findings to practical applications that improve human health. Literature has shown that meaningful community involvement can improve the research process itself, as well as the ultimate findings. Research questions about health issues that concern the community are developed, and people are more likely to give their support when they understand the purpose of the research, and how the results may positively affect them. Thus, this helps when recruiting participants. In addition, research questions help to identify the health risks that are revealed through people's participation, and helps with the development of appropriate ways to protect participants in this regard. Research questions also assist with improving study and instrument design by producing user-friendly, culturally sensitive, accurate and valid practices and measures. Furthermore, community involvement in analysis and interpretation can provide an important explanation of the results, and provide ideas that the researchers had not even considered. A community-engaged research approach provides an opportunity for greater trust and respect to be built between academic researchers and communities. This can lead to future research collaborations, as well as an improvement in community health. [ABSTRACT FROM AUTHOR]

Presents information on a study aimed at carrying out in-vitro antibiotic susceptibility testing on Helicobacter pylori strains isolated from patients with peptic ulcers and gastritis in Nigeria. Problems with the documentation of eradication rate of Helicobacter pylori; Reasons for high metronidazole and amoxycillin resistance; Drug combination for Helicobacter pylori treatment.

A total of 186 Helicobacter pylori isolates and 532 gastric biopsies recovered from 532 patients with varying degrees of gastroduodenal pathology are subjected to in vitro antibiotic susceptibility testing using the disc-diffusion method, Etest (MIC breakpoints) and molecular testing using the polymerase chain reaction (PCR). In the isolates studied, antibiotic resistance was as follows: piperacillin (72%), amoxicillin (66%), erythromycin (78%), tetracycline (100%) and metronidazole (95%). All isolates were sensitive to ofloxacin, ciprofloxacin and norfloxacin. None of the 245 amplicons (positive for H. pylori) from the biopsies were digested with the Bbs1 and Bsal restriction enzyme used in the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique, showing sensitivity to clarithromycin. However, a 238 bp fragment from H. pylori chromosomal DNA (corresponding to the quinolone resistance determining region [QRDR]) of the gyrA gene was amplified successfully. Twelve (4.9%) of the 245 strains studied had the described mutation at position 91, from asparagine (Asn) to glycine (Gly). The study showed that all the H. pylori strains were sensitive to clarithromycin and ciprofloxacin. It also highlighted PCR as a potential tool for faster diagnosis and determination of antibiotic susceptibility (within 24 h) of H. pylori from biopsies and/or isolates recovered from peptic ulcer and gastritis patients.

Aim: To comparatively evaluate PCR and other diagnostic methods (the rapid urease test and / or culture) in order to determine which of the three PCR methods (ureA, glmM and 26-kDa, SSA gene) was most appropriate in the diagnosis of Helicobacter pylori (H pylori ) infection and also to evaluate the detection of a putative virulence marker of H pylori, the cagA gene, by PCR in biopsy specimens., Methods: One hundred and eighty-nine biopsy specimens were collected from 63 patients (three biopsies each) undergoing upper gastroduodenal endoscopy for various dyspeptic symptoms. The PCR methods used to detect H pylori DNA directly from biopsies were the glmM, 26-kDa, ureA and then cagA was used to compare the culture technique and CLO for urease with the culture technique being used as the gold standard., Results: Thirty-five percent of the biopsies were positive for H pylori DNA using the 3 PCR methods, while 68% of these were positive for the cagA gene. Twenty-four percent of the biopsies were negative for H pylori DNA in all PCR methods screened. The remaining 41% were either positive for ureA gene only, glmM only, 26-kDa only, or ureA + glmM, ureA + 26-kDa, glmM + 26-kDa. Out of the 35% positive biopsies, 41% and 82% were positive by culture and CLO respectively, while all negative biopsies were also negative by culture and cagA. Cag A+ infection was also predominantly found in H pylori DNA of the biopsies irrespective of the clinical diagnosis., Conclusion: This method is useful for correctly identifying infections caused by H pylori and can be easily applied in our laboratory for diagnostic purposes.

We studied the efficacy of a home-made urease test (HUT) in the detection of Helicobacter pylori (HP) infection in patients undergoing upper gastrointestinal endoscopy. In the first phase of the study, two antral biopsies each were obtained from 43 patients for urease tests using the CLOtest and a home-made buffered 2% urea solution with phenol red as indicator at pH 6.8 (2% HUT). Twenty-six patients (60.5%) were HP positive, both by the 2% HUT and CLOtest with 100% concordance. In the second phase of the study three antral biopsies each and blood were obtained from 42 patients for the determination of HP status using a 10% HUT and a combination of culture and serology. Twenty-three patients (54.8%) were HP positive using the 10% HUT, while 32 patients (76.2%) were positive using the combination of 2 tests. Compared to this the sensitivity and specificity of the 10% HUT were 72% and 100% respectively. The CLOtest produced a colour change in a shorter time than the 2% and 10% HUT (median 1 hour versus 10 hours versus 16 hours p < 0.0001). In the third phase of the study, we observed that by doubling the biopsy size, the time required to obtain a colour change was significantly reduced (median 4.5 hours versus 10 hours p < 0.05). The HUT is easy to prepare, cheap, sufficiently sensitive and it is reliable enough to start treatment when positive. With 100% concordance and 1% the cost per test when compared to the commercially available CLOtest; the 10% HUT is hereby recommended for the detection of UP infection in our region.

Maintenance of gastric juxtamucosal pH at a stable near neutral value may be the cumulative effect of the various components of the mucosal defense system. In order to assess the effect of helicobacter pylori (HP) infection on mucosal defense, we measured the gastric antral juxtamucosal pH in 40 dyspeptic patients by using a flexible glass pH microelectrode which can be passed down the instrument channel of standard gastroscopes. HP status was determined using serology, culture, histology and urease test. We also investigated the relationship between juxtamucosal pH and the severity of antral HP infection. The mean antral juxtamucosal pH in 26 (65%) HP positive patients was 6.49 +/- 0.20 compared to 6.19 +/- 0.21 in 14 (35%) HP negative patients (p < 0.00001). Other factors like age, sex, duodenogastric reflux or presence of chronic duodenal ulcer did not significantly affect juxtamucosal pH (p > 0.05). Subset analysis of data on HP positive patients (n = 26) revealed no significant correlations between antral chronic gastritis anti-HP IgG titre and antral juxtamucosal pH (p > 0.05). This study shows that HP increases gastric antral juxtamucosal pH. This finding supports the suggested role of HP in producing hypergastrinaemia and gastric acid hypersecretion.

The pathological role of Helicobacter pylori is largely unproven in our region of high incidence of infection but very low incidence of serious gastroduodenal lesions. The aim of this study was to investigate the effect of H. pylori infection on gastric acid secretion. One week after gastroduodenoscopy, basal and pentagastrin (8 micrograms/kg) stimulated gastric acid secretion were measured in 39 dyspeptic Nigerians. H. pylori status was determined using urease test, culture, histology and serology, while gastritis was assessed using the Sydney system criteria. The median maximal acid output (MAO) and peak acid output (PAO) in mmol/h were significantly higher in H. pylori positive (29.3, range 7.4-81.6 and 34.4, range 7.6-144.0) than in H. pylori negative (16.6, range 4.2-44.1 and 22.4, range 5.6-48.6) patients, p = 0.019 and p = 0.029, respectively. Stimulated gastric acid secretion was significantly higher in patients with duodenal ulcer (n = 8) than in H. pylori negative (n = 11) patients, but was similar in non-ulcer dyspeptics (n = 20) and H. pylori negative patients. The median basal acid output was not significantly different between the groups of patients. Our patients (median age 32 years) had normal mucosa (12.1%), pangastritis with corpus predominance (12.1%), antrum-only gastritis (24.3%) and pangastritis with antral predominance (51.5%). In the subset of H. pylori positive patients (n = 28, 71.8%), there were no significant correlations between grade of antral chronic inflammation, gastritis index score, anti-H. pylori IgG titre and gastric acid secretion, p > 0.05. H. pylori infection increases MAO and PAO in our relatively young patients with antral predominant chronic gastritis.

Samples (98 plaque and 72 saliva) from 93 patients with dental caries were investigated for Lactobacillus species which comprised 65 (62.5%) of 104 isolates. Yeasts (20.1%), Streptococcus spp. (8.7%), Staphylococcus spp. (2.9%) and a few unidentified species (5.8%), were also found. The Lactobacillus isolates were L. brevis (24.6%) L. fermentum (18.5%) L. casei (16.9%), L. delbrueckii (15.4%), L. plantarum (9.23%), L. acidophilus (7.69%), L. jensenii (4.62%), L. salivarius (1.54%) and L. gasseri (1.54%). The most common species was L. brevis (24.6%). The strains tested for beta-lactamase production showed 75.4% positive. All the Lactobacillus strains were tested for bacteriocin production against Escherichia coli, Salmonella spp., Shigella dysenteriae, S. sonnei, Klebsiella spp. and Campylobacter sp. All the lactobacilli except L. jensenii produced bacteriocin against at least one of the indicator organisms. The involvement of Lactobacillus in dental caries was established, although its role and mechanism is not well understood. The ability of Lactobacillus spp. to protect their host against certain diseases by inhibiting the growth of potential pathogens was evident.