Clinicomycological Correlation of Tinea Incognito

Background: Tinea incognito refers to the unusual clinical manifestation of dermatophytosis brought on by prior topical or systemic medication use. Given the widespread and easy diagnosis of dermatophytic infections, steroid usage has created a diagnostic conundrum, thus turning a straightforward infection that may be treated into a persistent, long-term skin disease. Objective: To examine the clinical characteristics of tinea incognito and correlate the clinical manifestations with the microbiological findings. Methods: An observational study was conducted with 100 cases in a department of microbiology, dermatology, venereology, and leprology, in India. The baseline data of the patients and clinical features of tinea incognito were recorded. To identify the causative agents, skin scrapes were collected and tested as per standard protocol. Results: In this study, 30% of the patients were between 31 and 40 years old. The male-to-female ratio was 2:1, 66% reported a history of application of the triple combination of steroids, and 34% used single steroids. Tinea corporis was seen in 30% of the patients, and the trunk/body (52%) was the most frequent site, followed by other sites (34%). Potassium hydroxide positivity was observed in 75% of the cases, cultural positivity in 77%, and both tests were positive in 75%. The most common organisms found were T. mentagrophytes (72.7 (56/77)%), T. rubrum (19.5 (15/77)%), and T. tonsurens 7.8 (6/77)%. Conclusion: Tinea incognito is a fungal skin infection that can present with various nonspecific clinical features. This steroid-modified dermatophytosis is largely under-reported because the underlying fungal infection is masked by the irrational use of topical steroids