Department of Pathology-Microbiology, Faculty of Medicine, University of Jordan, 11942, Amman, Jordan.
BMC Pediatr. 2011 Sep 9;11:79. doi: 10.1186/1471-2431-11-79.
There is evidence that Candida colonization contributes to increasing invasion of candidiasis in hospitalized neonates. Few studies investigated the epidemiology and risk factors of Candida colonization among hospitalized and non-hospitalized infants. This prospective study investigated the major epidemiological characteristics of Candida species colonizing oral and rectal sites of Jordanian infants.
Infants aged one year or less who were examined at the pediatrics outpatient clinic or hospitalized at the Jordan University Hospital, Amman, Jordan, were included in this study. Culture swabs were collected from oral and rectal sites and inoculated on Sabouraud dextrose agar. All Candida isolates were confirmed by the Remel RapID yeast plus system, and further investigated for specific virulence factors and antifungal susceptibility MIC using E-test. Genotyping of C. albicans isolates was determined using random amplified polymorphic DNA (RAPD) analysis method.
A total of 61/492 (12.4%) infants were colonized with Candida species by either their oral/rectal sites or both. Rectal colonization was significantly more detected than oral colonization (64.6% verses 35.4%), particularly among hospitalized infants aged more than one month. The pattern and rates of colonization were as follows: C. albicans was the commonest species isolated from both sites and accounted for 67.1% of all isolates, followed by C.kefyr (11.4%), each C. tropicalis and C. glabrata (8.9%) and C. parapsilosis (3.8%). A various rates of Candida isolates proved to secrete putative virulence factors in vitro; asparatyl proteinase, phospholipase and hemolysin. C. albicans were associated significantly (P < 0.05) with these enzymes than other Candida species. All Candida isolates were susceptible to amphotericin B and caspofungin, whereas 97% of Candida species isolates were susceptible to fluconazole using E-test. The genetic similarity of 53 C. albicans isolates as demonstrated by dendrogram revealed the presence of 29 genotypes, and of these one genotype accounted for 22% of the isolates.
This study presents important epidemiological features of Candida colonization of Jordanian infants.
有证据表明,假丝酵母菌定植有助于增加住院新生儿侵袭性假丝酵母菌病的感染。很少有研究调查住院和非住院婴儿中假丝酵母菌定植的流行病学和危险因素。本前瞻性研究调查了约旦婴儿口腔和直肠部位定植假丝酵母菌种的主要流行病学特征。
本研究纳入了在约旦安曼的儿科门诊就诊或在约旦大学医院住院的年龄在 1 岁以下的婴儿。从口腔和直肠部位采集培养拭子并接种于沙氏葡萄糖琼脂。所有假丝酵母菌分离株均通过 Remel RapID 酵母加系统确认,并使用 E 试验进一步检测特定毒力因子和抗真菌药敏 MIC。通过随机扩增多态性 DNA(RAPD)分析方法确定白假丝酵母菌分离株的基因分型。
共有 61/492(12.4%)名婴儿的口腔/直肠部位或两者均被假丝酵母菌定植。直肠定植明显多于口腔定植(64.6%比 35.4%),尤其是 1 个月以上的住院婴儿。定植模式和率如下:口腔和直肠部位最常见的分离株均为白假丝酵母菌,占所有分离株的 67.1%,其次为卡氏假丝酵母菌(11.4%)、近平滑假丝酵母菌和光滑假丝酵母菌(各 8.9%)和近平滑假丝酵母菌(3.8%)。体外试验证明,不同比例的假丝酵母菌分离株可分泌潜在的毒力因子;天冬氨酸蛋白酶、磷脂酶和溶血素。白假丝酵母菌与这些酶显著相关(P<0.05),而其他假丝酵母菌则无此关联。所有假丝酵母菌分离株均对两性霉素 B 和卡泊芬净敏感,而 E 试验显示 97%的假丝酵母菌分离株对氟康唑敏感。53 株白假丝酵母菌分离株的遗传相似性通过聚类树状图显示存在 29 种基因型,其中一种基因型占分离株的 22%。
本研究揭示了约旦婴儿假丝酵母菌定植的重要流行病学特征。