SMALL-INTESTINAL BACTERIAL OVERGROWTH IN PATIENTS WITH RHEUMATOID-ARTHRITIS

Objectives-To examine the microflora of the upper small intestine in p atients with seropositive rheumatoid arthritis (RA) using a combinatio n of microbial cultivation and tests for microbial metabolic activity. Methods-Twenty five patients with seropositive RA, 12 achlorhydric co ntrol subjects, and 11 control subjects with normal gastric acid secre tion were investigated. Disease activity was evaluated in the patients with RA by three different indices. Eight (32%) of the patients with RA had hypochlorhydria or achlorhydria. The acid secetory capacity was determined with pentagastrin stimulation. A modified Crosby capsule w as used to obtain biopsy specimens and samples of intestinal fluid fro m the proximal jejunum; aerobic and anaerobic microbial cultivation of mucosal specimens/intestinal fluid was carried out, and gas productio n and microflora associated characteristics in jejunal fluid were dete rmined. Additionally, a bile acid deconjugation breath test was perfor med. Results-Subjects with at least one of the following findings were considered to have bacterial overgrowth: positive bile acid deconjuga tion test; growth of Enterobacteriaceae; positive gas production; or l ow tryptic activity. By these criteria half of the patients with RA wi th hypochlorhydria or achlorhydria and half of the achlorhydric contro ls had bacterial overgrowth. Thirty five per cent of the patients with RA with normal gastric acid secretion had bacterial overgrowth compar ed with none of the normal controls. Disease activity indices and rheu matoid factor titres were significantly higher in patients with RA wit h bacterial overgrowth than in those without. Conclusions-A high frequ ency of small intestinal bacterial overgrowth was found in patients wi th RA; it was associated with a high disease activity and observed in patients with hypochlorhydria or achlorhydria and in those with normal acid secretion.