Onychomycosis: Is colour change a hallmark of the disease?

Nail colour changes were examined in 91 mycologically confirmed cases of onychomycosis. Dermatophytes were the most common fungi seen in 63 patients, followed by Candida in 16 patients and non-dermatophytic moulds in 12 cases. Clinico-aetiological correlation was determined with special reference to variegate colour changes. None of the patients had any clinical evidence of skin or systemic disease, drug reaction or chemical application. Colour change was the most common sign and symptom observed in all patients (100%). Predominant colour changes caused by dermatophytic infection were yellowish-brown (95%) and greyish-white (100%), p<0.05. In contrast, non-dermatophytic moulds exhibited greenish discoloration (100%), p<0.05. Candidal infection did not show any significant correlation with a particular colour change. Colour change is a hallmark of onychomycosis and the appearance of yellowish-brown and greyish-white discoloration is suggestive of dermatophytic nail infection while greenish discoloration indicates mould infection.