Fungal nail infection - Onychomycosis

Low urgency
Common-

It is an infection of the fingernails and toenails, which modifies their thickness and color, thus altering their appearance.

It is caused by fungi that live in the skin.

It presents with whitish or yellowish, brittle, fragile and deformed nails.

The diagnosis will be made by examination of the nails. It can be confirmed by microscopic examination of nail scrapings or by a mycological culture of a sample. 

The treatment of choice is an oral antifungal for a prolonged period of time.  In cases refractory to treatment, it may be necessary to remove the nail to achieve a definitive cure.  

Bibliographic references
  1. Adam O Goldstein. Onychomycosis: Epidemiology, clinical features, and diagnosis. UpToDate. Abril 2016
  2. Adam O Goldstein. Onychomycosis: Management. UpToDate. Septiembre 2016
  3. de Berker D. Clinical practice. Fungal nail disease. N Engl J Med 2009; 360:2108.
  4. Gupta AK. Update in antifungal therapy of dermatophytosis. Mycopathologia 2008; 166:353.
  5. Leslie P. Lawley. Eccema, psoriasis, infecciones cutáneas, acné y otros trastornos cutáneos frecuentes. Harrison. Principios de Medicina Interna, 19e. Capítulo 71
Author
Dr. Patricia Sánchez
Copyright
© TeckelMedical 2026

Symptoms

    White and/or yellowish nail


    Cracked nails


    Nails fall off the fingers / toes


    Nail-flaking


    Pain in the nail

Symptoms to watch out for

Bleeding around the nails
Swelling or pain around the nails
History of immunodeficiency (HIV, Diabetes Mellitus, oncological disorders, long-term corticosteroid consumption).
Fever (temperature higher than 100.4 ºF)
Difficulty walking without help

Self-care

Apply over-the-counter topical antifungals.
Trim and file the nails.
Avoid prolonged sweating of the feet, change socks twice a day.
Wear shoes in the pool and locker room areas.
Avoid sharing footwear.
Dry feet well, especially between the toes.