Role of Tinea Unguium and Other Factors in Chronic and Recurrent Dermatophytosis: A Case Control Study

CONTEXT: There is an alarming rise in the incidence of chronic and recurrent dermatophytosis (CRD) in India. Many factors including tinea unguium may be responsible for it. AIMS: To evaluate various epidemiological and clinical factors including the presence of tinea unguium as a risk factor for CRD. SETTINGS AND DESIGN: This was a case-control study in which patients attending the dermatology outpatient department of a tertiary care hospital in February–March 2019 were recruited. A total of 80 consecutive clinically diagnosed patients with CRD as per the case definition (cases) were selected. Another 80 consecutive patients with dermatophytosis other than CRD (controls) were also selected. Patients were clinically evaluated with special attention for the presence of tinea unguium. RESULTS: Among the total of 80 cases, 44 (55%) and 36 (45%) were diagnosed to have chronic dermatophytosis and recurrent dermatophytosis respectively. CRD was relatively uncommon in patients younger than 20 years. Sharing of linen, family history, and topical corticosteroid abuse were also frequent among patients with CRD. Tinea unguium was present in six cases (7.5%) and two controls (2.5%) which was not statistically significant (P = 0.27). CONCLUSIONS: The current epidemic of CRD may be primarily due to a pathogen with certain specific epidemiological and clinical determinants. It may be primarily a skin pathogen with less or no affinity toward the hair and nail.