Tinea capitis in AdultSee also in: Hair and Scalp
Alerts and Notices
SynopsisTinea capitis is also known as scalp ringworm. It is an infection caused by dermatophyte species of fungi, most often those of the genera Trichophyton and Microsporum. Some of the most common causative species in the United States are Trichophyton tonsurans, Microsporum audouinii, and Microsporum canis. The condition manifests as numerous scaly lesions and patches of broken hair on the scalp. Lesions may suppurate and evolve into kerions. Two patterns of infections are recognized: ectothrix and endothrix. An ectothrix infection involves the outside of the hair shaft, while an endothrix infection involves the inside. Tinea capitis is most commonly encountered in children, but it is also seen in adults. Contact with animals or immunosuppression (HIV, corticosteroid therapy, renal transplantation) may predispose adults to infection. Some adults have tinea capitis that went untreated in childhood.
Majocchi-like granulomas, deep ulcerated fungal infections, severe tinea capitis and corporis, and fungal nail involvement are characteristic of an inherited deficiency of CARD9 (caspase recruitment domain-containing protein 9), an inflammatory cascade-associated protein. The disorder is autosomal recessive and is most common in North Africa countries including Algeria, Morocco, and Tunisia. The infections usually begin in childhood and are caused by Trichophyton rubrum and Trichophyton violaceum. Lymphadenopathy, high IgE antibody levels, and eosinophilia are common, and the disorder can be fatal.
B35.0 – Tinea barbae and tinea capitis
5441008 – Tinea capitis
Differential Diagnosis & Pitfalls
Patient Information for Tinea capitis in Adult
OverviewTinea capitis is the medical term for ringworm, a very common fungal infection, of the scalp. Despite the name, there are no worms involved in scalp ringworm, rather the rash forms a scaly, round patch that sometimes clears or improves in the middle, thus looking like a ring. Ringworm can occur on other parts of the body, but scalp ringworm is commonly seen in children. It is contagious and is acquired by contact with infected people, animals, or objects (such as towels, combs, and pillows). Scalp ringworm should be treated (by a prescription medicine your doctor can prescribe) because it is contagious and because, if left untreated, the affected area can develop hair loss and sometimes another, more serious, infection called a kerion.
Who’s At RiskAnyone can get scalp ringworm, though it is most commonly seen in children under the age of 10. In the United States, African American children are more likely to have scalp ringworm than others. Boys are more commonly affected than girls.
Signs & SymptomsThe most common locations for scalp ringworm include:
- Eyebrow (rare)
- Eyelash (very rare)
The lymph nodes at the back of the scalp, behind the ears, or along the sides of the neck may be swollen.
One complication of scalp ringworm is a kerion, a large, oozing, pus-filled lump. If not treated aggressively, a kerion can lead to scarring and permanent hair loss.
Scalp ringworm is usually itchy.
Self-Care GuidelinesThere are no effective self-care measures to treat scalp ringworm.
In order to prevent scalp ringworm, be sure to avoid close contact with infected people and pets. Do not share combs, brushes, hats, and hair accessories with friends.
When to Seek Medical CareIf you have hair loss or itchy, scaly spots on the scalp, it is probably a good idea to make an appointment with a physician.
If a sibling, classmate, or friend is diagnosed with scalp ringworm, make sure you examine your own scalp to look for scaly spots. If you are suspicious about an area, see a doctor for an examination.
If you are diagnosed with scalp ringworm, make sure any household pets are evaluated by a veterinarian to be certain that they do not also have a dermatophyte infection. If the veterinarian discovers an infection, the animal should be treated.
TreatmentsIn order to confirm the diagnosis of scalp ringworm, your physician may wish to scrape some surface skin material onto a slide and examine it under a microscope. This procedure, called a KOH (potassium hydroxide) preparation, allows the doctor to look for tell-tale signs of fungal infection.
The doctor may also wish to perform a fungal culture in order to document the presence of fungus or to discover the particular organism that is causing the scalp ringworm. The procedure involves:
- Plucking a few hairs from involved areas of scalp
- Rubbing a sterile cotton-tipped applicator across the skin to collect scale and any pus
- Sending the specimen away to a laboratory
Occasionally, a Wood's lamp is used to look for the fungus. In this exam, the doctor shines a black light at the scalp, and certain types of dermatophyte may appear as yellow-green fluorescent spots.
Scalp ringworm is treated with oral antifungal medicines because the fungus invades deep into the hair follicle, where topical creams and lotions cannot penetrate. Scalp ringworm usually requires at least 6-8 weeks of treatment with oral antifungal pills, including:
- Selenium sulfide shampoo
- Ketoconazole shampoo
Bolognia, Jean L., ed. Dermatology, pp.1174-1185. New York: Mosby, 2003.
Freedberg, Irwin M., ed. Fitzpatrick's Dermatology in General Medicine. 6th ed. pp.645-646, 1993-1995, 2443-2446. New York: McGraw-Hill, 2003.
Tinea capitis in AdultSee also in: Hair and Scalp