Diseases that Cause Hair Loss and Alopecia

The medical term for hair loss is alopecia. Alopecia can be a side effect of another illness or it can be the predominant feature of the disease. Alopecia can be further divided into scarring and non-scarring conditions. In scarring alopecia, hair follicles are permanently damaged and the chance of re-growth is almost nonexistent.

Alopecia Areata

Alopecia aratea is an autoimmune disease that typically causes circular spots of hair loss. It tends to run in families and occurs when a person's white blood cells attack the hair follicles. Hair loss ranges from patches on the head and beard to loss of all hair on the scalp. In 90% of cases, the hair re-grows without treatment.

Telogen Effluvium

This condition is characterized by the widespread shedding of hair. It occurs when a large number of hair follicles prematurely enter a rest cycle. This is often caused by a traumatic event including acute illness, hormonal changes, major surgery, anesthesia and big life changes. The condition is not permanent and the hair will grow again.

Tinea Capitis

Tinea capitis is a fungal infection that causes hair loss in children. Symptoms include white scaly flakes on the head or a large blister that covers the scalp. Lymph nodes under the ear and on the back of the neck may swell. If treated in the early stages, hair growth should return to normal.

Thyroid Conditions and Alopecia

The thyroid gland regulates the body's metabolism. If the gland is over or underactive, it can affect hair growth causing it to become thin and sparse, or dry, brittle and sparse. Once the thyroid problem has been treated, hair growth should return to normal.

Dietary Problems

Hair loss can sometimes be caused by dietary problems including anemia, diabetes, malnutrition, anorexia and bulimia.

Alopecia caused by Medications

There are a number of medications that cause hair loss but the most well known are the drugs used for treating cancer. Chemotherapy can cause rapid hair loss but this is generally not long lasting. Once the treatment ends, hair growth will begin.

Lupus and Hair Loss

Lupus is an autoimmune disease that causes inflammation of organ tissue. It causes hair loss in up to 50% of sufferers and this can be permanent or temporary. The area around the temples is commonly affected and hair loss is often patchy.

Scarring Alopecia

Scarring alopecia causes invisible scarring beneath the scalp and hair follicles are replaced with scar tissue. This condition is caused by the body's immune system attacking the skin and hair follicles. This usually results in permanent hair loss.

Hair loss or alopecia can be caused by several diseases and the problem may be temporary or permanent. Each condition affects hair growth in different ways and some may cause small spots of baldness while others cause total hair loss. It is important to seek medical help for alopecia as many of the causes are treatable.

Reference:
Hair Loss & Replacement for Dummies, William R Rassman, Wiley Publishing Inc, 2009