Other causes of hair loss
Alopecia areata (AA) is a recurrent disease, which can cause hair loss in any hair-bearing area. The most common type of alopecia areata presents as round or oval patches of hair loss most noticeably on the scalp or in the eyebrows. The hair usually grows back within 6 months to one year. Most patients will suffer episodes of hair loss in the same area in the future. Those who develop round or oval areas of hair loss can progress to loss of all scalp hair (alopecia totalis). The cause of alopecia areata is unknown but commonly thought to be an autoimmune disorder (the body does not recognize the hair follicles and attacks them). Stress and anxiety are frequently blamed by patients as the cause of their hair loss.
60% of cases in this disease are self limited. The most common treatment is with steroids (cortisone is one form) either topically or by injection. The outcome of treatment is good when the alopecia areata process is present less than one year and poor, especially in adults, if the disease has been present for longer periods of time. Minoxidil (Rogaine) can help to regrow hair. Surgical treatment of this disorder is not recommended if the disease is active.
|60% of cases in this disease are self limited
Hair loss due to scarring of the scalp is called scarring alopecia. Scarring can be due to a variety of causes. Traction alopecia over a period of time may lead to scarring and permanent hair loss. Trichotillomania (compulsive hair-plucking) can cause permanent scalp scarring over time.
Injury to the scalp caused by physical trauma or burns may leave permanent scars and permanent hair loss. Diseases that may cause permanent hair loss due to scalp scarring include (1) the autoimmune conditions lupus erythematosus and scleroderma, and (2) bacterial infections such as folliculitis, fungal infections, and viral infections such as shingles (herpes zoster).
Scarring alopecia from burn
See Hair transplant over scarred scalp
Traction alopecia is caused by chronic traction (pulling) on the hair follicle and is seen most commonly in African-American females associated with tight braiding or cornrow hair styles, pony tail. It is generally present along the hairline. Men who attach hairpieces to their existing hair can experience this type of permanent hair loss if the hairpiece is attached in the same location over a long period of time. Trichotillomania is a traction alopecia related to a compulsive disorder caused when patients pull on and pluck hairs, often creating bizarre patterns of hair loss.
Trichotillomania is the name given to habitual, compulsive plucking of hair from the scalp or other hair-bearing areas of the body. Over time, continual plucking of scalp hair will result in a hairless area-a bald spot. Long-term trichotillomania can result in permanent damage to scalp skin and to scarring alopecia. It is not known whether trichotillomania should be classified as a habit or as obsessive-compulsive behavior. In its mildest form, trichotillomania is a habitual plucking of hair while a person reads or watches television. In its more severe forms, trichotillomania has a ritualistic pattern and the hair-plucking may be conducted in front of a mirror. The person with trichotillomania often has guilt feelings about his or her "odd" behavior and will attempt to conceal it.
Consult with psychiatry, psychology, or developmental-behavioral pediatrics specialists.
Patients present with diffuse hair loss after an exposure to drugs or toxic chemicals. Chemotherapeutic agents are most commonly responsible for hair loss. Other medications that can cause anagen effluvium include bismuth, levodopa, colchicine, and cyclosporine. Hair loss usually begins 7-14 days after a single pulse of chemotherapy. The hair loss is clinically most apparent after 1-2 months.
- Although topical minoxidil is not effective in preventing chemotherapy-induced alopecia, it shortens the period of baldness by about 50 days.
- The application of a pressure cuff around the scalp and local hypothermia retard anagen arrest, if these measures are implemented during the infusion of medication.
- Anagen effluvium is entirely reversible.
- Upon the cessation of drug therapy, the follicle resumes its normal activity within a few weeks.
- In some cases, hair regrows despite continued or maintenance therapy.
- On occasion, the color and texture of the hair that regrows after chemotherapy-induced alopecia is different from those of the original hair.
Telogen effluvium is a form of non-scarring alopecia characterized by diffuse hair shedding, often with an acute onset. A chronic form with a more insidious onset and a longer duration also exists. Telogen effluvium is a reactive process caused by a metabolic or hormonal stress or by medications. Generally, recovery is spontaneous and occurs within 6 months.
The symptom of both acute and chronic telogen effluvium is increased hair shedding. Patients usually only complain that their hair is falling out at an increased rate. Occasionally, they note that the remaining hair feels less dense. In both forms of telogen effluvium, hair is lost diffusely from the entire scalp. Complete alopecia is not seen.
- Acute telogen effluvium is defined as hair shedding lasting less than 6 months. Patients with acute telogen effluvium usually complain of relatively sudden onset of hair loss. Careful questioning usually reveals a metabolic or physiologic stress 1-6 months before the start of the hair shedding. Physiologic stresses that can induce telogen effluvium include febrile illness, major injury, change in diet, pregnancy and delivery, and starting a new medication. Immunizations also have been reported to cause acute hair shedding. Papulosquamous diseases of the scalp, such as psoriasis and seborrheic dermatitis, can produce telogen effluvium.
- Chronic telogen effluvium is hair shedding lasting longer than 6 months. The onset is often insidious, and it can be difficult to identify an inciting event. Because of the duration of the hair shedding, patients are more likely to complain of decreased scalp hair density, or they may note that their hair appears thin and lifeless.
Physiologic stress is the cause of telogen effluvium. These inciting factors can be organized into several categories, noted below. In humans, however, the role these effects play in hair loss has not yet been determined.
- Acute illness such as febrile illness, severe infection, major surgery and severe trauma
- Chronic illness such as malignancy, particularly lymphoproliferative malignancy; and any chronic debilitating illness, such as systemic lupus erythematosus, end-stage renal disease, or liver disease
- Hormonal changes such as pregnancy and delivery (can affect both mother and child), hypothyroidism, and discontinuation of estrogen-containing medications
- Changes in diet like crash dieting, anorexia, low protein intake, and chronic iron deficiency
- Heavy metals such as selenium, arsenic, and thallium
Medications, of which the most frequency cited are beta-blockers, anticoagulants, retinoids (including excess vitamin A), propylthiouracil (induces hypothyroidism), carbamazepine, and immunizations
- Allergic contact dermatitis of the scalp
- Because acute telogen effluvium is a reactive process, which resolves spontaneously, treatment usually is limited to reassurance.
- While chronic telogen effluvium is less likely to resolve rapidly, reassurance is appropriate for these patients. Often, the knowledge that the hair loss will not progress to baldness is comforting to the patient. The patient should be encouraged to style the hair in a way, which masks any perceived defects in hair density.
- Any reversible cause of hair shedding, such as poor diet, iron deficiency, hypothyroidism, or medication use, should be corrected.
- While topical minoxidil is not proven to promote recovery of hair in telogen effluvium, this medication has a theoretical benefit and is well tolerated. Patients who are eager to play an active role in their treatment may choose to use minoxidil.
Hair transplantation is not an effective treatment for telogen effluvium.
- Prognosis is good for recovery of normal hair density in acute telogen effluvium. A good cosmetic outcome can be expected in chronic telogen effluvium, even if hair shedding continues.