"Condições clínicas e a presença de leveduras em cavidade bucal de pacientes portadores de doença renal crônica"

Abstract

Immunosuppressive conditions of the chronic kidney disease (CKD) on hemodialysis (HD) or post-kidney transplant (TX), predispose patients to the development of oral lesions (OL) and colonization by yeasts in the oral cavity, the latter with high risk of progressing to fungal infections such as candidemia. However, the scarce and contradictory information on the issue indicate the need for further investigations. Thus, the general objective of this thesis was to evaluate the correlation between the colonization by, and the different species of, yeasts with the oral status of patients with CKD under HD and TX. The specific objectives were to verify, in the oral cavity of patients with CKD: (1) the incidence of yeasts in association with the presence of OLs and the use of dental prostheses; (2) the incidence of tongue coating (TC) and the presence of yeasts on it; and (3) the rate of colonization by yeasts in patients one year after TX, and its association with their oral and systemic clinical status. The study population was comprised by patients with CKD stage 5 in HD and TX. Stimulated salivary flow test, and anamnesis and physical examination of the oral mucosa, in which patients' habits and systemic and oral clinical status were registered, were conducted. Salivary and tongue samples were collected and analyzed by mycological examinations. In the first study, 42.31% of patients were colonized by yeasts, 100% of them belonging to the genus Candida, with predominance of C. albicans (69.23%). Half of the patients presented some type of OL, the majority (63.33%) suggestive of candidiasis. The presence of OL and the use of prosthesis increased the chances of yeast isolation in 6.33 and 2.62 times, respectively. In the second study, TC was the most common OL (78.26%). Among the samples collected, 13 (72.22%) from the tongue dorsum, and one (5.55%) from the saliva were positive for yeasts. The presence of yeasts on the tongue dorsum was significant (p = 0.0106) in relation to the saliva. There was a predominance of C. albicans (55.55%) while C. parapsilosis comprised 50% of non-albican Candida species. In the last study, the salivary cultures were positive for yeasts in 29% of the patients. There was a significant association between the presence of yeasts with xerostomia, diabetes mellitus, hypertension and lack of oral care in the pre-TX phase. All yeasts were of the Candida genus, with predominance of C. albicans. It can be concluded that: (1) in HD patients, the occurrence of OLs and the colonization rates by yeasts were high, especially in patients with removable dental prosthesis; (2) TC was the most common OL, with high incidence of yeasts, suggesting tongue biofilm formation; 3 - TX patients with xerostomia, diabetes mellitus, hypertension and no history of oral care in the pre-TX phase should be monitored through oral and mycological clinical examinations. Such actions would help guiding the nephrology anamnesis, preventing problems such as oral candidiasis, and would consequently reduce the risk of systemic infections such as disseminated candidiasis.