Helicobacter pylori: prevalence and antibiotic susceptibility among Kenyans.
BACKGROUND
Helicobacter pylori infection in Kenya is staggeringly high. Evidence links infection of the gastric mucosa by H. pylori with subsequent development of gastric pathologies.


OBJECTIVE
We investigated the prevalence of H. pylori in dyspeptic patients, its relationship with gastric pathologies, and associated antibiotic susceptibility profiles, and compared two media to find the appropriate medium that enhances growth and expedites culture and isolation.


METHODS
Rapid urease and histological tests were used to screen for H. pylori. Culture was performed to test sensitivity and evaluate media. Selective and nutritional supplements were added to culture media (Colombia blood agar and brain-heart infusion agar) for growth enhancement. E-test strips for metronidazole, amoxicillin and clarithromycin were used for susceptibility testing.


RESULTS
The prevalence of H. pylori infection in children was 73.3%, and 54.8% in adults. All the H. pylori investigated in this study were largely sensitive to clarithromycin (100%, minimum inhibiting concentration (MIC) <2 microg/ml), amoxicillin (100%, MIC <2 microg/ml) and metronidazole (95.4%, MIC <8 microg/ml). There was, however, occasional resistance to metronidazole (4.6%, MIC >8 microg/ml). Both Colombia blood and brain-heart infusion agar, with the supplements, effectively supported H. pylori growth. Growth was achieved in an average of 36 hours for primary isolations and 24 hours for subcultures.


CONCLUSIONS
The media described here reduce the time required to culture and isolate bacteria and perform susceptibility testing. Despite the high prevalence of H. pylori infection, the associated pathology is low and does not parallel H. pylori prevalence in the population.
Kimang'a
Andrew Nyerere
AN
Medical Microbiology Subdepartment, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya. kinyerere@yahoo.com
Revathi
Gunturu
G
Kariuki
Samuel
S
Sayed
Shahin
S
Devani
Smita
S
D000328:Adult; D000658:Amoxicillin / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D044383:Black People / Q000706:statistics & numerical data*; D002648:Child; D017291:Clarithromycin / Q000627:therapeutic use; D015331:Cohort Studies; D024881:Drug Resistance, Bacterial; D004415:Dyspepsia / Q000382:microbiology*; D016481:Helicobacter Infections / Q000175:diagnosis / Q000188:drug therapy* / Q000208:ethnology*; D016480:Helicobacter pylori; D006801:Humans; D007630:Kenya; D008795:Metronidazole / Q000627:therapeutic use; D008826:Microbial Sensitivity Tests; D015995:Prevalence
D000900:Anti-Bacterial Agents; D008795:Metronidazole; D000658:Amoxicillin; D017291:Clarithromycin