Co-trimoxazole impairs colonization resistance in healthy volunteers

Abstract

The influence of co-trimoxazole on colonization resistance of the bowel was investigated in six healthy volunteers, by measuring the numbers of indigenous aerobic flora and of a co-trimoxazole resistant challenge strain of Klebsiella pneumoniae. Impairment of colonization resistance of the bowel was shown by a significant increase in the numbers of yeasts in the faeces of five of six volunteers, by a significant increase in the numbers of Gram-negative bacilli in the faeces of two of six volunteers, and by facilitation of colonization of the bowel by the challenge strain in all volunteers. Impairment of colonization resistance of the mouth was shown by the development of glossitis caused by Candida albicans in two volunteers, and by a significant increase in the numbers of yeasts in mouth washings from four volunteers. It is concluded that co-trimoxazole impairs colonization resistance of the gastro-intestinal tract.

Colonization resistance

“…Apart from enterococci, staphylococci or streptococci colonized the bowel in some of our volunteers at low concentrations ('105 CFU/g of feces) (57)(58)(59)(60)(61)64).…”

“…However, the initial regimens of selective decontamination in neutropenic patients contain co-trimoxazole (12), and most regimens used in patients on mechanical ventilation contain cefotaxime (54). It has now been proven that neither of these agents spares CR (61,64). Consequently, the very success of these regimens implies that selectivity is not necessary for efficacy in decontamination of the bowel.…”

“…All 18 volunteers treated with cefotaxime, clindamycin, or co-trimoxazole became colonized with these strains. Subsequently, these strains remained detectable in feces for variable periods of time up to 3 weeks after treatment (57,61,64). Concurrently, cefotaxime and clindamycin increased the concentration of enterococci in feces and all three antimicrobial agents increased the concentration of yeasts in feces.…”

From Structure to Function: the Ecology of Host-Associated Microbial Communities

“…Cotrimoxazole, for instance, was used to disrupt the human microbiota. This resulted in colonization of the colon by an experimentally introduced invader in all subjects, as well as a Candida albicans infection of the mouth in two of the volunteers (346). Because of the ethical issues faced when infecting humans with known pathogens, animal models are often used to investigate community resistance to pathogen invasion.…”

Pathogenetische Bedeutung der intestinalen Candidabesiedelung

“…gegenüber der bakteriellen Darmflora, zu einer Überwuche-rung des Darmes mit Hefen kommen, so dass die Candidazahlen über 10 5 KBE/g Stuhl ansteigen; außerdem setzt vermehrte Mycelbildung ein [84,101,106,107,110,111,112,113,114,115,116,117]. Zur Bedeutung der bakteriellen Flora s. Levy [105].…”