Candida species are common in the human oral microbiota and may cause oral candidiasis (OC) when the microbiota equilibrium is disturbed. Immunosuppressed individuals are susceptible to oral infections as individuals with Down syndrome (IDS) due to particularities of their mouth morphoanatomy, saliva and comorbidities. This study aimed to analyze the molecular epidemiology of Candida spp. from the oral cavity of IDS and their relatives. A case–control study with 80 IDS and 80 non-syndromic (non-DS) was evaluated by oral swab collection for culture on Sabouraud dextrose agar, selection of yeast colonies to Gram staining and culturing on chromogenic media. DNA extraction was performed with the phenol/chloroform method for screening of 6 Candida species medically important in PCR, applying SPSS for statistics. We confirmed four species in 46 IDS without use of antimicrobials (57.54%), with a high prevalence of C. albicans/Ca (93.48%/43) and 3 C. glabrata/Cg (6.52%), being 25 of these IDS (31.25%) colonized by species other than C. albicans: Ca + Cg (16), Ca + C. tropicalis/Ct (7) and Ca + C. krusei/Ck (2). Only 10 non-DS were colonized by one species (11.25%): 6 C. albicans, 2 C. glabrata, 1 C. tropicalis and 1 C. krusei. Previous OC was reported by 39 IDS (48.75%), being 33 positives for Candida spp. (84.61%) and 17 with active OC (21.25%). Five non-DS reported OC previously and had no active lesions. Behavioral changes and buccal health programs directed to IDS may help prevent OC and its recurrence, providing information on oral hygiene for self-care.

念珠菌物种在人类口腔微生物群中很常见，当微生物群平衡受到干扰时，可能导致口腔念珠菌病（OC）。由于其口腔形态解剖，唾液和合并症的特殊性，免疫抑制的个体像唐氏综合症（IDS）个体一样易受口腔感染。本研究旨在分析念珠菌的分子流行病学。来自IDS及其亲属的口腔。通过口服拭子收集，在Sabouraud葡萄糖琼脂上培养，选择酵母菌落进行革兰氏染色和在生色培养基上培养，评估了一项包含80个IDS和80个非综合症（非DS）的病例对照研究。用苯酚/氯仿法进行DNA提取，以筛选6种念珠菌在PCR中具有重要医学意义的物种，应用SPSS进行统计。我们在46个IDS中确认了四种不使用抗菌剂的物种（57.54％），其中白色念珠菌/ Ca（93.48％/ 43）和3 glabrata / Cg（6.52％）的患病率很高，在这些IDS中占25个（ 31.25％）被白色念珠菌以外的物种定居：Ca  +  Cg（16），Ca  +  C.tropicis / Ct（7）和Ca  +  krusei / Ck（2）。6：10只无DS由一个物种（11.25％）定殖白色念珠菌， 2光滑念珠菌，1个热带念珠菌和1克柔念珠菌。39个IDS（48.75％）报告了先前的OC，对假丝酵母属呈阳性33 。（84.61％）和17位活跃的OC（21.25％）。五个非DS先前报告过OC，并且没有活动性病变。针对IDS的行为改变和口腔健康计划可能有助于预防OC及其复发，提供有关口腔卫生的信息以进行自我护理。