Ringworm

Definition

Ringworm is a common fungal infection of the skin. The name is a misnomer because the disease is not caused by a worm.

Description

Ringworm is characterized by patches of rough, reddened skin. Raised eruptions usually form the circular pattern that gives the condition its name. As lesions grow, the centers start to heal. The inflamed borders expand and spread the infection. Ringworm may also be referred to as dermatophyte infection. It is more common in males than females, and is most common among children ages three to nine years.

Types of ringworm

Ringworm is a term that is commonly used to encompass several types of fungal infection. Sometimes, however, only body ringworm is classified as true ringworm.

Body ringworm (tinea corporis) can affect any part of the body except the scalp, feet, and facial area where a man's beard grows. The well-defined, flaky sores can be dry and scaly or moist and crusty.

Scalp ringworm (tinea capitis) is most common in children. It causes scaly, swollen blisters or a rash that looks like black dots. Sometimes inflamed and filled with pus, scalp ringworm lesions can cause crusting, flaking, and round bald patches. Most common in black children, scalp ringworm can cause scarring and permanent hair loss.

Ringworm of the groin (tinea cruris or jock itch) produces raised red sores with well-marked edges. It can spread to the buttocks, inner thighs, and external genitals.

Ringworm of the nails (tinea unguium) generally starts at the tip of one or more toenails, which gradually thicken and discolor. The nail may deteriorate or pull away from the nail bed. Fingernail infection is far less common.

Demographics

Ringworm can affect people at any age. It is more common among children, athletes, and people with poor hygiene habits.

Causes and symptoms

Ringworm can be transmitted by infected people or pets or by towels, hairbrushes, or other objects contaminated by them. Symptoms include inflammation, scaling, and sometimes, itching.

Diabetes mellitus increases susceptibility to ringworm. Dampness, humidity, and dirty, crowded living areas also increase susceptibility. Braiding hair tightly and using hair gel also raise the risk.

When to call the doctor

A health professional should be consulted when signs of ringworm appear or if exposure to someone with ringworm is suspected.

Diagnosis

Diagnosis is based on microscopic examination of scrapings taken from lesions. A dermatologist may also study the scalp of a person with suspected tinea capitis under ultraviolet light.


Advertisement
Advertisement