Ringworm

Some people experience itching and bald spots as a result of infection with tinea capitis, a contagious fungus also known as ringworm. The U.S. National Library of Medicine cites additional symptoms of the disorder that may include unusually dark or light skin and raised, red patches that sometimes blister.

Alopecia Areata

Some individuals lose round patches of scalp hair as a result of a disorder called alopecia areata. Researchers do not clearly understand the underlying causes of this condition, which may disappear and reappear multiple times.

Seborrheic Dermatitis

Scalp itchiness may also result from the common condition seborrheic dermatitis, which can also trigger dandruff formation. The Mayo Clinic cites potential causes for this condition such as yeast, bacteria, fatigue, stress, nerve disorders such as Parkinson's disease, seasonal changes of weather and HIV/AIDS infection.

Considerations

Ringworm may also appear on the body, feet or groin.

Additional Considerations

Some individuals may experience a form of alopecia areata that triggers baldness across the entire scalp. This condition is called alopecia totalis.

Source:

U.S. National Library of Medicine-National Institutes of Health: Ringworm

The Mayo Clinic-Seborrheic Dermatitis (Pages 1-3)

U.S. National Library of Medicine-National Institutes of Health: Alopecia Areata