It is a fungal nail infection (onychomycosis) of dermatophytic origin (1).
Tinea unguium is a white decoloration of the nail in which there is subungual hyperkeratosis with separation of the nail plate from the bed. The nail becomes thickened and friable. Toenails (particularly the great toenail) are involved more commonly than the fingernails (2).
Some commonly seen clinical subtypes are:
Concomitant tinea pedis can be seen in most of the patients (2).
Reference:
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