Department of Health Sciences, İstanbul Kent University, İstanbul, Turkey.
Department of Medical Microbiology, Medical Faculty, Pamukkale University, Denizli, Turkey.
Mycoses. 2022 Jul;65(7):704-708. doi: 10.1111/myc.13450. Epub 2022 May 25.
Lipophilic basidiomycetous yeasts of the Malassezia genus can cause various skin diseases, such as seborrheic dermatitis, pityriasis versicolor, folliculitis and atopic dermatitis, and even life-threatening fungemia in newborns and immunocompromised individuals. Routine mycological media used in clinical practice do not contain sufficient lipid ingredients required for the growth of Malassezia species. A recently developed medium, FastFung agar, is promising for culturing fastidious fungal species.
In this study, we compared FastFung agar and mDixon agar for culturing Malassezia species from nasolabial fold and retroauricular specimens of 83 healthy individuals and 187 and 57 patients with acne vulgaris and seborrheic dermatitis, respectively.
Malassezia species were identified using conventional tests and matrix-assisted laser desorption/ionisation mass spectrometry. In total, 96 of 654 samples (14.6%) contained Malassezia species. The total isolation rate was significantly higher in patients with seborrheic dermatitis (40.4%) than in healthy volunteers (21.7%; p < .05), and the rate of M. furfur isolation was significantly higher for patients with acne vulgaris (13.9%) and seborrheic dermatitis (24.6%) than for healthy individuals (1.5%; p < .05). FastFung agar was superior to mDixon agar in M. furfur isolation (p = .004) but showed similar performance in the case of non-M. furfur species (p > .05). Among cultured Malassezia species, perfect agreement between mDixon agar and FastFung agar was found only for M. globosa (κ = 0.90).
Our results indicate that FastFung agar favours the growth of Malassezia species and should be useful in clinical mycology laboratories.
马拉色菌属的亲脂性担子菌酵母可引起各种皮肤疾病,如脂溢性皮炎、花斑癣、毛囊炎和特应性皮炎,甚至在新生儿和免疫功能低下的个体中引起危及生命的真菌血症。临床实践中常用的常规真菌培养基不含马拉色菌属生长所需的足够脂质成分。最近开发的一种培养基,FastFung 琼脂,对于培养难培养的真菌种具有很大的潜力。
在这项研究中,我们比较了 FastFung 琼脂和 mDixon 琼脂在培养来自 83 名健康个体的鼻唇沟和耳后标本以及分别患有寻常痤疮和脂溢性皮炎的 187 名和 57 名患者的马拉色菌属的效果。
使用常规试验和基质辅助激光解吸/电离质谱鉴定马拉色菌属。总共,654 个样本中有 96 个(14.6%)含有马拉色菌属。脂溢性皮炎患者(40.4%)的总分离率明显高于健康志愿者(21.7%;p<0.05),且痤疮患者(13.9%)和脂溢性皮炎患者(24.6%)的 M. furfur 分离率明显高于健康个体(1.5%;p<0.05)。FastFung 琼脂在分离 M. furfur 方面优于 mDixon 琼脂(p=0.004),但在非 M. furfur 种的情况下表现相似(p>0.05)。在所培养的马拉色菌属中,仅 M. globosa 在 mDixon 琼脂和 FastFung 琼脂之间存在完美的一致性(κ=0.90)。
我们的结果表明,FastFung 琼脂有利于马拉色菌属的生长,应该对临床真菌学实验室有用。