Rapid Identification of Medically Important Molds by an Oligonucleotide Array

• Main Authors: Chen-Ren Hsiao, 蕭淳仁
• Other Authors: Tsung-Chain Chang
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/72856415278087341068

碩士 === 國立成功大學 === 醫事技術學系 === 92 === 　　Mold infection is increasing in recent years. Because of the advance of medical science and the growing population of immumocompromised, bone marrow transplantation and solid organ transplantation patients, fungi become important pathogens. Accurate and rapid identification of molds causing infections is important for appreciate patient treatment with antifungal agents. The conventional identification methods of molds heavily rely on the morphological characteristics and biochemical tests. Some fungal species may grow slowly and are morphologically indistinguishable, so the conventional methods are sometimes not suitable. We utilized ribosomal RNA internal transcribed spacer (ITS) sequence and an oligonucleotide array to identify clinically relevant molds. Specific probes were designed from the ITS sequences and were spotted onto a nylon membrane. The ITS regions of molds were amplified by PCR and hybridized to probes on the membrane chip. The hybridization results were visualized by color development on the chip. In this study, 57 specific probes were spotted on an 1.1 cm × 0.9 cm chip, which was used to identify 65 species, belonging to 34 genera. A total of 258 reference strains were tested and a sensitivity of 98.5% (196/199) was obtained, whereas the specificity was 93.2% (55/59). Seventy one clinical isolates were tested and the sensitivity was 94.4% (51/54), however the specificity was 88.2% (15/17). The sensitivities for the identification of 7 Aspergillus species including 53 reference strains and 22 clinical isolates were both 100%. In conclusion, oligonucleotide array is a powerful tool to rapidly and accurately identify most important mold pathogens.