No relationship between gastric pH, small bowel bacterial colonisation, and diarrhoea in HIV-1 infected patients

Gut. 1999 Jan;44(1):101-5. doi: 10.1136/gut.44.1.101.


Background/aims: Conclusive studies of small bowel bacterial overgrowth in patients with HIV-1 infection are limited. The relation was therefore determined between the quantity and species of bacteria in the proximal small intestine of HIV-1 infected patients and the presence of diarrhoea, gastric acidity, severity of immune deficiency, and clinical outcome.

Methods: Bacteria in the duodenal fluids obtained endoscopically from 32 HIV-1 infected patients, 21 of whom had diarrhoea, and seven control subjects without HIV-1 risk factors were quantified and speciated. Gastric pH was determined at the time of endoscopy. Clinical follow up was performed to assess outcome.

Results: Oropharyngeal Gram positive cocci were present in fluids from 28 patients (88%). Gram negative aerobic or facultatively anaerobic bacteria were present in fluids from 12 patients (38%), and strict anaerobes were detected in six patients (19%), but for both groups colony counts infrequently exceeded 10(4) colony forming units/ml. The number and species of bacteria did not correlate with the presence of diarrhoea, gastric pH, or CD4 lymphocyte count.

Conclusions: Small bowel bacterial overgrowth is not common in HIV-1 infected patients, regardless of the presence of diarrhoea, and is not associated with hypochlorhydria

MeSH terms

  • AIDS-Related Opportunistic Infections / microbiology
  • Adult
  • Algorithms
  • Bacteria / isolation & purification
  • CD4 Lymphocyte Count
  • Diarrhea / microbiology*
  • Duodenum / microbiology*
  • Follow-Up Studies
  • Gastric Juice / metabolism*
  • HIV Infections / immunology
  • HIV Infections / microbiology*
  • HIV-1*
  • Humans
  • Hydrogen-Ion Concentration
  • Prospective Studies