Crespo Erchiga V, Ojeda Martos A, Vera Casaño A, Crespo Erchiga A, Sanchez Fajardo F
Servicio de Dermatología, Complejo Hospitalario Carlos Haya, C/Especerias 7, 29005 Málaga, Spain.
Br J Dermatol. 2000 Oct;143(4):799-803. doi: 10.1046/j.1365-2133.2000.03779.x.
The taxonomic revision carried out in 1996 on the genus Malassezia, which now comprises seven different species, made necessary a re-evaluation of the data concerning the ecology and pathogenicity of these lipophilic yeasts. Very little has been published since then.
The aim of this work was to contribute to the knowledge of the aetiology of pityriasis versicolor (PV) with a mycological study made according to the new species.
Ninety-six patients with PV completed the study. In all of them, samples were taken from the lesions for direct microscopy with KOH+ Parker ink and culture. Samples were also taken from normal skin of the trunk and the forehead of the same patients for culture. Cultures were made in modified Dixon medium in Petri dishes, incubated at 31 degrees C and the isolates were identified by morphological and physiological characteristics.
In the PV lesions, direct microscopy always showed the typical mixture of globose blastoconidia and pseudomycelium. Only one patient, having received previous topical antimycotic treatment, was negative. The spherical yeasts observed in vivo were morphologically identical to the globose yeasts characteristic of M. globosa. In culture, M. globosa was found in 97% of cases, alone in 60% of them and associated with M. sympodialis in 29% and M. slooffiae in 7%. These two species were also found in similar percentages on the clinically uninvolved skin of the trunk, whereas M. globosa was not isolated at these sites. However, on the forehead, a small number of colonies of M. globosa was recovered in 12% of cases.
These results support the data previously reported and strongly suggest that M. globosa in its mycelial phase is the causative agent of PV.
1996年对马拉色菌属进行了分类修订，该属现包含七个不同的物种，这使得有必要重新评估有关这些亲脂性酵母的生态学和致病性的数据。从那时起，相关的公开报道很少。
本研究旨在通过根据新物种进行的真菌学研究，为花斑糠疹（PV）的病因学知识做出贡献。
96例PV患者完成了本研究。对所有患者，从皮损处取材进行KOH + 派克墨水直接显微镜检查和培养。还从同一患者的躯干和前额正常皮肤取材进行培养。培养物接种于改良的迪克森培养基平皿中，在31℃下孵育，并根据形态和生理特征鉴定分离株。
在PV皮损中，直接显微镜检查始终显示典型的球形芽生孢子和假菌丝混合物。只有一名先前接受过局部抗真菌治疗的患者为阴性。体内观察到的球形酵母在形态上与球形马拉色菌的球形酵母特征相同。在培养中，97%的病例中发现了球形马拉色菌，其中60%为单独存在，29%与合轴马拉色菌相关，7%与斯洛菲马拉色菌相关。在躯干临床未受累皮肤中也发现了这两个物种，比例相似，而在这些部位未分离到球形马拉色菌。然而，在前额，12%的病例中分离到少量球形马拉色菌菌落。
这些结果支持了先前报道的数据，并强烈表明处于菌丝体阶段的球形马拉色菌是PV的病原体。
