Mycological Aspects of Gastrointestinal Microflora

Abstract

There are two aspects about the presence of Candida in the human orointestinal tract: (i) it is a part of normal human flora and (ii) it is a risk factor for immunocompromised patients. The orointestinal tract can be considered a reservoir for Candida species, several of which are from the oral cavity, stomach, duodenal juice and faeces. Their germ counts in normal small and large bowel do not exceed 10(4) cfu/ml resp.g. The input of Candida to a well-developed faecal flora system under continuous flow culture conditions did not lead to a multiplication of the yeast. The take in of faecal flora into a Candida continuous flow culture diminish Candida germ counts. If, however, the faecal flora was destroyed, e.g. by antibiotics, we found the yeasts multiplying, with the formation of germ tubes and mycelial structures. Colonization by Candida has to be seen as a starting-point of the development of subsequent candidosis in immunosuppressed or intensive care patients. The best protection against Candida colonization in the gut is the existence of a normal bacterial flora. Lactulose, which promotes the Gram-positive potential of faecal flora, may protect indirectly by supporting the indigenous flora.

Oral Candida spp. colonization in human immunodeficiency virus-infected individuals

“…Excessive growth of Candida spp. at those colonization sites may facilitate tissue invasion, mainly in predisposed hosts (8).…”

Prospective evaluation of Candida species colonization in hospitalized cancer patients: impact on short-term survival in recipients of marrow transplantation and patients with hematological malignancies

“…9,17,19 As mentioned earlier, most infections originate from endogenous host reservoirs, and the orointestinal tract is though to be the principle source for hematogenous invasion, especially in critically ill patients at risk of fungal dissemination. 22,23 Experiments using animal models suggest that high-grade, sustained Candida gastrointestinal tract colonization increases the risk of systemic yeast dissemination and prior to bloodstream invasion a disruption of the mucosal barrier was consistently found among immunosuppressed animals. 24,25 We report no statistically significant difference in the impact of colonization of either respiratory, orointestinal or urinary tract on short-term survival (P Ͼ 0.5).…”

Role of Hormones and Neuropeptides in IBS and other Gastrointestinal Disorders: Understanding Variability and Chrononutrition

“…It is by understanding variability in human subjects, e.g. increasing gut microflora from proximal small bowel to ileum [168,169], through the science of chronobiology, that variability may be exploited for chronotherapy.…”