Understanding the dynamics of onychomycosis: a common nail infection

Onychomycosis is the most common nail infection predominantly caused by the dermatophytes. It is more common in the toenail as compared to the fingernails. The common risk factors include older age, diabetes, comorbidities, smoking, use of tight shoes for prolonged time, and so forth. It is also common among the cases with preexisting mucocutaneous candidiasis. Trichophyton rubrum and Trichophyton mentagrophytes constitute up to 60% of the cases. Based on the part of the nail involved, there are different types of onychomycosis like the white superficial onychomycosis, distal lateral subungual onychomycosis, proximal ungula onychomycosis, and so forth. In India, the prevalence of onychomycosis caused by dermatophytes can range from 0.2 to 41%, prevalence rate is affected by many factors across the country. The common diagnostic methods are KOH microscopy and culture; however, newer visual techniques are coming up with higher sensitivity. Dermoscopy and confocal microscopy are some newer techniques for rapid visualization while PCR, Raman spectroscopy, lateral flow assay methods: are employed for detection of fungus. Artificial intelligence is also being developed for quick diagnosis and management of onychomycosis. For the treatment of onychomycosis, oral as well as topical antifungal agents are available, oral agents are fast in action but there is a risk of side effects while topical agents are free from risk of side effects but takes longer time. Itraconazole and terbinafine are the common oral drugs and tavaborole and efinaconazole are topical agents.