癌症病童口腔念珠菌感染之分析研究

Isolation and Identification of Oral Candida Species in Child Cancer Patients

盧建佑(CHIEN-YU LU)

指導教授 ： 李憲明 ； 黃芳亮

中臺科技大學/健康科學院/生物科技暨醫學工程研究所/碩士(2017年)

摘要

兒童癌症病患常因化學治療，引發白血球低下、口腔黏膜受損，而導致口腔念珠菌感染。以傳統培養方法檢測其感染曠日廢時，若利用分子檢測分析真菌rRNA的內轉錄間隔區（internal transcribed spacer, ITS），則可簡便、快速篩檢大量樣品。為了探討癌症病童之口腔念珠菌感染情形，本研究收集55位癌症病童及25位正常族群之oral rinse solution，首先使用Real-time PCR針對ITS篩選真菌陽性之樣品，再挑選陽性之病童與對照組樣品各 15 個，利用Length heterogeneity-polymerization chain reaction (LH-PCR) 進行菌種的鑑定。此外，另行挑選陽性之病童與對照組樣品各5個進行次世代定序 (Next Generation Sequencing, NGS），分析病患與正常族群口腔真菌菌叢的多樣性以及數量的差異。病患檢體之LH-PCR分析中，C. albicans、C. parapsirosis、C. dubliniensis與C. guilliermondi之組成比例平均值高於對照組。在NGS的結果中，5個病患檢體的C. albicans、C. glabrata、C. parapsirosis與C. tropicalis數目，其中至少一種明顯高於對照組。上述結果顯示：一、LH-PCR和NGS可有效評估於兒童癌症病患口腔念珠菌感染；二、癌症病童之口腔真菌以念珠菌為主。

關鍵字

兒童癌症病患 ； 口腔念珠菌感染 ； 內轉錄間隔區

並列摘要

Side effects of chemotherapy, leukopenia and oral mucosa injury, often caused oral candidal infection in child cancer patients. The traditional culturing methods for the diagnosis of Candida infection are time consuming and laborious. Instead, molecular genetic analysis of internal transcribed spacer (ITS) regions of fungal rRNA provided a simple and rapid way to screen a large amount of samples. To investigate the prevalence of oral candidiasis in child cancer patients, the oral rinse solution from 55 child cancer patients and 25 healthy controls were collected in this study, and screened for Candida specific ITS signal by real-time PCR. Then, 15 child cancer patient and 15 control samples showing Candida specific ITS signal were chosen for fungal species identification by length heterogeneity-polymerization chain reaction (LH-PCR). Furthermore, additional 5 child cancer patients and the same amount of control samples were analyzed by next generation sequencing (NGS) to find out the diversity and abundance of Candida species in these samples. In the analysis of LH-PCR, the mean composition ratios of C. albicans, C. parapsirosis, C. dubliniensis and C. guilliermondii in patients were higher than controls. The NGS results demonstrated that the abundance of Candida species in patients is significantly higher than controls, at least one species among C. albicans, C. glabrata、C. parapsirosis and C. tropicalis. These results suggest that LH-PCR and NGC are useful techniques for assessing the severity of oral candidal infection in child cancer patient, and Candida is the most predominant fungi in oral cavity of child cancer patients.

並列關鍵字

child cancer patients ； oral candidal infection ； ITS ； LH-PCR ； NGS

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