Intestinal microflora in a chronic carrier of vibrio cholerae

Bacterial populations of the small and large intestine were examined in a chronic carrier of Vibrio cholerae el tor. Vibrios were present throughout the small bowel, although the highest concentrations were noted in duodenal fluid after stimulation of the gallbladder. The numbers of vibrios were markedly reduced in the cecum and disappeared in the ascending colon. Normally passed stools were usually negative for vibrios but became positive during diarrhea, either occurring naturally or induced by saline purgation, and during administration of polymyxin B. The vibrio carrier state was terminated after 2 days of treatment with tetracycline, and the patient remained free from vibrios during subsequent follow-up examinations. Small numbers of coliforms were also present in the duodenum and jejunum of this cholera carrier. Despite transient reduction during treatment with tetracycline, these organisms persisted for an additional 1-2 months after vibrio clearance and then disappeared spontaneously. Similar persistence of coliforms has also been noted in patients convalescing from cholera who did not become vibrio carriers. Malabsorption of vitamin B₁₂ and D-xylose and abnormal jejunal histology were found in this patient. B12 absorption improved after treatment with tetracycline and may have been related to direct intraluminal binding of this substance by vibrios.