Department of Veterinary Microbiology, Faculty of Veterinary Medicine, Institute of Preclinical Veterinary Sciences, University of Life Sciences, Lublin, Poland.
Department of Mycology and Genetics, Faculty of Biological Sciences, Institute of Genetics and Microbiology, University of Wroclaw, Wroclaw, Poland.
J Appl Microbiol. 2021 Jan;130(1):278-291. doi: 10.1111/jam.14778. Epub 2020 Jul 21.
Accurate identification of dermatophytes is essential for implementing appropriate antifungal treatment and epidemiological analysis. However, the limitations of conventional diagnostics are a frequently discussed topic, and new diagnostic techniques are constantly expanding. In this study, we assess the suitability of conventional diagnostic techniques in comparison to the real-time PCR assay and MALDI-TOF MS in detection and identification of dermatophytes.
Strains included in this study were obtained from human and animals with symptomatic, and asymptomatic infection. A direct examination revealed that 31·7 and 60·9% of samples from symptomatic patients, and 25·7 and 60% from asymptomatic animals were positive, as shown by light and fluorescence microscopy respectively. In turn, dermatophytes were isolated from 90·2 and 71·4% of these samples. The pan-dermatophyte primers in real-time PCR assay facilitated detection in 85·3 and 82·9% of the symptomatic and asymptomatic dermatophytoses respectively. Additionally, species-specific PCR assays were positive in 70·7 and 37·1% of these samples. The MALDI-TOF MS analysis yielded positive results consistent with conventional techniques in 97·2 and 72% of symptomatic and asymptomatic infections respectively.
Our study revealed that there is no universal diagnostic method that would be ideal in each of the cases considered. Nonetheless, conventional techniques are still the most effective and reliable tools for mycological diagnostics.
Dermatologists and veterinarians have difficulties in making a diagnosis of dermatophytoses based only on observed symptoms of fungal infections, as they mimic symptoms of other dermatoses. In this context, a comparative analysis of the results of diagnostics performed using conventional methods and new technologies are crucial for implementing these pioneer methods into routine laboratory practice.
准确鉴定皮肤癣菌对于实施适当的抗真菌治疗和流行病学分析至关重要。然而，常规诊断的局限性是一个经常讨论的话题，新的诊断技术也在不断扩展。在这项研究中，我们评估了传统诊断技术与实时 PCR 检测和 MALDI-TOF MS 在检测和鉴定皮肤癣菌方面的适用性。
本研究纳入的菌株来自有症状和无症状感染的人和动物。直接镜检显示，在有症状的患者中，31.7%和 60.9%的样本，以及在无症状的动物中，60%和 60%的样本，分别通过亮场和荧光显微镜观察为阳性。反过来，从这些样本中分离出 90.2%和 71.4%的皮肤癣菌。实时 PCR 检测中的泛皮肤癣菌引物分别有助于检测 85.3%和 82.9%的有症状和无症状皮肤癣病。此外，这些样本中，70.7%和 37.1%的样本的种特异性 PCR 检测呈阳性。MALDI-TOF MS 分析在 97.2%和 72%的有症状和无症状感染中与常规技术的结果一致。
我们的研究表明，在考虑的每种情况下，没有一种通用的诊断方法是理想的。尽管如此，常规技术仍然是最有效的和可靠的用于真菌学诊断的工具。
皮肤科医生和兽医仅根据真菌感染的观察到的症状来诊断皮肤癣病存在困难，因为它们模仿其他皮肤病的症状。在这种情况下，对使用常规方法和新技术进行的诊断结果进行比较分析对于将这些先驱方法引入常规实验室实践至关重要。
