Chapter 29-18: Tinea Corporis

TEXTBOOK PRESENTATION

Tinea corporis commonly presents as round, pink plaques with small peripheral papules and a rim of scales. The neck and back are the most common locations (Figure 29-12).

DISEASE HIGHLIGHTS

1. Description of the lesion: multiple lesions are possible.

   1. Circular lesions with a sharply marginated raised border and central clearing, arising by centrifugal spread of the fungus from the initial site of infection

   2. Inflammatory lesions may demonstrate pustules or vesicles, especially around the margin.

   3. Overlying scale is common, typically more prominent at the border of the lesion.

   4. Solitary lesions may occur, or there may be multiple plaques that remain discrete or become confluent.

2. The degree of associated inflammatory change is variable, depending on the causative species of fungus.

3. The wide variation in clinical presentation depends on the species of fungus, size of the inoculum, body site infected, and immune status of the patient.

EVIDENCE-BASED DIAGNOSIS

1. Microscopic identification of fungal elements after application of 5–20% potassium hydroxide (KOH) solution to lesional scrapings collected on a microscope slide

2. Culture of tissue material (such as lesional scrapings)

3. Histopathology is rarely necessary to make the diagnosis of a superficial infection, but with the use of special stains (periodic acid-Schiff or Gomori methenamine silver) the fungal elements may be visible in fixed sections.

TREATMENT

1. Both topical and systemic antifungal agents are effective. The choice is determined by the extent and location of the infection.

2. Hair-bearing sites often require systemic therapy.