Association between gastrointestinal tract carriage of Candida, blood group O, and nonsecretion of blood group antigens in patients with peptic ulcer.

Of 112 patients with peptic ulcer disease examined for oral carriage of Candida, 66 (59%) were carriers. Candida carriage was associated with blood group O (P < 0.05) and, independently, with nonsecretion of blood group antigens (P < 0.01). For each subject, the presence or absence of yeasts was found to be a constant characteristic, and only among patients positive for Candida was blood group O or nonsecretion more frequent than expected in the general population. The quantity of yeasts isolated was significantly greater in patients than in normal subjects (P < 0.002), as was the frequency of carriage in the patient population (59% vs 32%). This increase was not associated with treatment with H2-receptor antagonists. The results of paired oral and gastroduodenal aspirate cultures suggested that identifying Candida in the oral cavity was a good indicator of the presence of yeasts elsewhere in the gastrointestinal tract. Mechanisms whereby overgrowth of Candida in the upper gastrointestinal tract might contribute to the inflammatory background of peptic ulcer disease are discussed.