Athlete’s foot, ringworm, and dhobi itch are some of the names by which we commonly know cutaneous fungal infections.
How does one get a fungal infection?
Fungal infections or Tinea are caused by infection of the skin, hair, or nail by the growth of fungi. These may occur over any part of the skin, however, the presence of wet skin with occlusion (in between toes in people who wear closed shoes, under the breasts, groin area), humid environment increases the chances of infection. People with immunosuppression (diabetics) may experience more infections than the general population.
How can dermatologists diagnose fungal infection?
Fungal infections can be diagnosed by their clinical presentation. Often, they appear as concentric reddish rings with central clearing (hence the term ringworm). However, over the scalp, it can present as patches of hair loss and pus. Over the hands and feet, it can present as whitish areas in the web spaces or scaly plaques over the feet and hands.
The diagnostic test involves a scraping of the affected area, which is then mounted under KOH and observed under a microscope. The fungal hyphae can be easily identified. The fungal culture tests are also available but they can take up to 4 weeks to show growth. They are restricted to diagnose drug-resistant fungal infections and for research purposes.
How are fungal infections treated?
Fungal infections are treated with a combination of topical antifungal creams and oral antifungals. The duration of treatment depends on the site of infection. Skin infections resolve quicker with improvement seen in 2 weeks post-treatment, infections over the scalp, hands, and feet may take up to a month of treatment. Nail infections usually will take over 3 months for complete resolution.
As the oral antifungals are hepatotoxic, there is a need to check the liver function before the commencement of antifungal treatments, as well as during treatments.
Why should one avoid OTC creams for fungal infections?
Most OTC creams contain a combination of antifungals and steroid creams. Steroid creams can mask the inflammation, allowing the infection to spread. They can also mask the signs of infection, making diagnosis difficult. This condition is known as Tinea Incognito or Steroid modified Tinea.