Ringworm (Dermatophyte Fungal Infection of the Skin)

Definition

Ringworm refers to a skin infection caused by the Tinea species of fungi and not by a worm. Also known as dermatophytoses, ringworm can affect the nails or skin of different areas. There are various different types of fungi that can infect the skin but dermatophytes have an affinity for the skin. These are the most common types of fungal skin infections.

Types

Various Tinea species causing ringworm include the following:

  • T. barbae, affecting skin in the beard area and causing barber’s itch
  • T. corporis, affecting body skin
  • T. pedis, affecting the feet and causing athlete’s foot
  • T. cruris, affecting the groin area and causing jock itch
  • T. capitis, affecting the skin of the scalp
  • T. unguium, affecting the fingernails and toenails

Of all these infections, ringworm of the feet, groin and scalp are more common.

Symptoms

Symptoms of ringworm usually include appearance of a ring-like rash on the affected skin. Most of the times, the rashes have sharply defined edges. Different subtypes of ringworm infection may show the following symptoms:

  • Skin ringworm: A ring-like, itchy rash on the skin with red and inflamed edges and healthy-looking core. Area may darken over time.
  • Scalp ringworm: One or more circular, tender or painful patches of scaly or red skin just above the scalp. Patches grow in size. Hairs become brittle or fragile. Hair loss is common. In the case of severe infection, a large, tender and inflammatory scalp mass called kerion is formed. A kerion may have crust and pustules and may look like an abscess.
  • Jock itch: Presence of rash in the skin folds of the groin, which may spread to the buttocks or inner thighs.
  • Barber’s itch (beard ringworm): Superficial ring-like lesions.
  • Athlete’s foot: Red and scaly skin. Thickening and scaling of the soles may also be found.

Causes

Ringworm is a common skin infection. It can affect people of all ages, especially young children. Ringworm is caused when the Tinea fungus grows and multiplies on the skin. It has specialized enzymes that allows it to consume the dead keratinized skin cells. These infections are superficial and do not penetrate deeper into the body.

Ringworm spreads easily from one person to another through direct touch, skin-to-skin contact or by sharing personal items, clothing or personal spaces. Animals are common carriers of the fungi and humans can catch ringworm infection from them as well. Tinea fungi thrives in warm, moist areas and can easily grow on moist, sweaty skin or on sites of minor injuries on the skin, nails, or scalp.

Treatment

Treatment depends on the type of ringworm and severity of infection. Treatment options may include the following antifungal choices:

  • Daily dose of terbinafine, itraconazole or griseofulvin for 2-3 weeks is recommended for beard ringworm. In cases of severely inflammation, prednisone may also be given.
  • Griseofulvin, imidazole, terbinafine or ciclopirox are given to children treat scalp ringworm. Selenium sulfide shampoos are also effective. Adults are given terbinafine or itraconazole with prednisone.
  • For mild infection of body ringworm, imidazole, ciclopirox, naftifine, or terbinafine-based creams, lotions, or gels can be used. Oral itraconazole or terbinafine is recommended in severe or resistant ringworm infection.
  • Jock itch can be successfully treated with include ketoconazole, terbinafine, naftifine, miconazole, clotrimazole, econazole, or ciclopirox. Itraconazole or terbinafine are given to patients with treatment-resistant, widespread, or inflammatory infections.
  • For athlete’s foot, itraconazole or terbinafine can be given. Drying agents like antifungal powders (for example, miconazole), Burow’s solution, gentian violet, or aluminum chloride hexahydrate should also be applied to avoid moisture in the affected areas.

More Related Topics