Jung M Y, Shim J H, Lee J H, Lee J H, Yang J M, Lee D-Y, Jang K-T, Lee N Y, Lee J-H, Park J-H, Park K K
Department of Dermatology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Clin Exp Dermatol. 2015 Jul;40(5):479-84. doi: 10.1111/ced.12593. Epub 2015 Feb 16.
Traditionally, the gold standard for diagnosis of onychomycosis has been the combination of direct microscopy with potassium hydroxide (KOH) staining and fungal culture. However, several studies have suggested that periodic-acid-Schiff (PAS) staining of nail-plate clippings may be a very sensitive method for the diagnosis of onychomycosis.
To compare the sensitivities of direct microscopy with KOH, fungal culture and PAS staining of nail-plate clippings, and to define an efficient, high-yield and cost-effective diagnostic strategy for the diagnosis of onychomycosis in the clinical setting.
We evaluated a total of 493 patients with clinically suspected onychomycosis. Group A comprised 400 patient samples, evaluated using fungal culture and PAS stain, while group B comprised 93 patient samples evaluated using KOH, fungal culture and PAS. Diagnosis of onychomycosis was defined as clinical morphology plus at least one positive test result.
In group A, sensitivities of fungal culture and PAS were 49.5% and 93.1% (P < 0.005), respectively. In group B, the most sensitive single test was PAS (88.2%) followed by KOH (55.9%) and fungal culture (29.4%). The combination of fungal culture and PAS (94.1%) was significantly (P < 0.001) more sensitive than that of KOH and culture (72.1%).
PAS staining of nail clippings is much more sensitive than KOH and fungal culture for the diagnosis of onychomycosis. Based on our results, we propose a diagnostic algorithm for onychomycosis that takes into consideration the sensitivity, cost-effectiveness and necessary time for each test.
传统上，甲癣诊断的金标准是氢氧化钾（KOH）染色直接显微镜检查与真菌培养相结合。然而，多项研究表明，甲板剪取物的过碘酸希夫（PAS）染色可能是诊断甲癣的一种非常敏感的方法。
比较KOH直接显微镜检查、真菌培养和甲板剪取物PAS染色的敏感性，并确定一种在临床环境中诊断甲癣的高效、高产且具有成本效益的诊断策略。
我们共评估了493例临床疑似甲癣的患者。A组包括400例患者样本，采用真菌培养和PAS染色进行评估，而B组包括93例患者样本，采用KOH、真菌培养和PAS进行评估。甲癣的诊断定义为临床形态学加上至少一项阳性检测结果。
在A组中，真菌培养和PAS的敏感性分别为49.5%和93.1%（P<0.005）。在B组中，最敏感的单项检测是PAS（88.2%），其次是KOH（55.9%）和真菌培养（29.4%）。真菌培养和PAS联合检测（94.1%）的敏感性显著高于KOH和培养联合检测（72.1%）（P<0.001）。
甲板剪取物的PAS染色在诊断甲癣方面比KOH和真菌培养敏感得多。基于我们的结果，我们提出了一种甲癣诊断算法，该算法考虑了每种检测的敏感性、成本效益和所需时间。
