Division of Pathology, Department of Pathology and Microbiology, Nihon University School of Medicine, and Nihon University Itabashi Hospital, 30-1 Oyaguchi-Kamimachi, Itabashi-ku, Tokyo 173-8610, Japan.
Histopathology. 2010 Feb;56(3):372-83. doi: 10.1111/j.1365-2559.2010.03477.x.
Although Trichosporon is a causative pathogen of white piedra and summer-type hypersensitivity pneumonitis, fatal disseminated trichosporonosis cases have recently been increasing. However, Trichosporon is often confused with other fungi, especially Candida, in pathological specimens. The aim was to determine the utility of histopathological stains and electron microscopy for diagnosing trichosporonosis.
Autopsy cases of trichosporonosis, candidiasis, aspergillosis and cryptococcosis were investigated using histopathological stains and electron microscopy. Using Grocott's method, Trichosporon was weakly detected compared with other fungi. In contrast, diluted periodic acid methenamine silver (PAM) stain clearly enhanced the intensity of staining of Trichosporon compared with Candida. Furthermore, Alcian blue and colloidal iron stains predominantly detected Trichosporon. Electron microscopy after staining with diluted PAM demonstrated that Trichosporon has a variety of hyphal sizes and laminar deposition of rough silver granules, whereas Candida has uniform pseudohyphae and fine granules. The average diameter and population area of the granules were significantly higher in Trichosporon compared with Candida (P<0.01). Meanwhile, the laminar structure was preserved in the cell walls of Trichosporon without silver stains, whereas a low-density structure was observed in Candida.
Histopathological staining patterns and electron microscopic findings can facilitate the diagnosis of trichosporonosis.
虽然申克孢子丝菌是白色念珠菌病和夏型过敏性肺炎的致病病原体，但最近致命性播散性申克孢子丝菌病的病例正在增加。然而，在病理标本中，申克孢子丝菌常与其他真菌（尤其是假丝酵母菌）混淆。本研究旨在确定组织病理学染色和电子显微镜在诊断申克孢子丝菌病中的应用价值。
对申克孢子丝菌病、假丝酵母菌病、曲霉菌病和隐球菌病的尸检病例进行了组织病理学染色和电子显微镜检查。与其他真菌相比，使用 Grocott 法时，申克孢子丝菌的检出较弱。相比之下，稀释后的过碘酸-雪夫（PAS）银染色法能明显增强申克孢子丝菌的染色强度，而假丝酵母菌的染色强度则减弱。此外，阿尔辛蓝和胶体铁染色主要检测到申克孢子丝菌。用稀释后的 PAS 染色后的电子显微镜显示，申克孢子丝菌具有多种大小的菌丝和层状沉积的粗糙银颗粒，而假丝酵母菌则具有均匀的假菌丝和细颗粒。与假丝酵母菌相比，申克孢子丝菌的颗粒平均直径和群体面积明显更高（P<0.01）。同时，在未进行银染色的申克孢子丝菌细胞壁中保留了层状结构，而假丝酵母菌则观察到低密度结构。
组织病理学染色模式和电子显微镜检查结果有助于申克孢子丝菌病的诊断。
