How to Diagnose the Exact Cause of Alopecia or Hair Loss?

June 9, 2018

[caption id="attachment_281" align="aligncenter" width="300"] Diagnosis of Hair Loss includes extensive history taking and investigations.[/caption]

Treatment of hair loss depends upon finding and treating the cause of alopecia. Hence diagnosing the cause of alopecia is the first step in the effective management of hair loss. This involves extensive history taking, thorough examination of the hear bearing areas and doing relevant lab tests. What makes the alopecia an enigma is that even after such thorough clinical approach, the cause of hair loss may still remain a mystery,

As we have already seen in the previous article on different types of hair loss, alopecia can either be scarring or non-scarring. Androgenic alopecia or male pattern baldness, alopecia areata, and telogen effluvium are examples for non-scarring alopecia.

Taking extensive history about the hair loss is of utmost importance in making a diagnosis as to the cause of the hair loss. Your dermatologist may ask the following questions:

How long have you been experiencing hair loss?

Is the hair loss gradual or sudden?

Whether extensive or localized and patchy?

Any associated symptoms like itching, scaling, burning sensations etc?

Has the patient noticed hair thinning also, in addition to hair loss? Gradual hair thinning and hair loss may be due to male and female pattern baldness.

Do you feel tired all the time(anemia)?

Any history of hormonal imbalances (Thyroid disease or hyperandrogenism)

Is hair pulling test positive? In hair shedding due to telogen effluvium and alopecia areata, hair pulling test will be positive.

Any history of recent illnesses, trauma, stress, medications?

While doing hair pulling test, is the hair coming out along with the root or is it breaking on traction?

Hair pull test (coming out as a whole with root) is positive in:

Telogen effluvium

Alopecia areata

Androgenic alopecia

Drug induced hair loss

When hair breaks on pulling, showing hair shaft weakness, the causes may be:

Tinea capitis (fungal infection)

Use of hair straighteners and other abrasive hair cosmetic treatments

Hair shaft abnormalities

Hair growth retardation

In females, a detailed menstrual history is important to rule out hormonal causes

Is there hair loss in other body parts as well??

Is there a family history of hair loss? A genetic predisposition has to be ruled out.

What are your food habits? Balanced nutrition is essential for normal hair growth.

How often do you expose your skin to sun? Vitamin D deficiency is an important cause for chronic hair loss and hair thinning.

What is hair pulling test?

This is a simple and easy test to assess the status and degree of hair loss.

Hold around 50- 60 hairs firmly between the thumb, index, and middle fingers , near the base of hair shaft. Pull firmly along the direction of hair follicle.

If more than 10% (5-6) whole hairs (with roots) come out from the scalp, the hair pull test is considered as positive. Shampooing should be avoided at least 1 day before.

Trichoscopy for Hair Loss

Trichoscopy (dermoscopy of hair) is very useful in outpatient diagnosis of hair loss causes. Being non-invasive it carries better patient acceptance as well.

Laboratory investigations in alopecia:

Essential tests in case of chronic hair loss:

Serum ferritin

Hemoglobin

Vitamin D3, Serum Zinc and Calcium levels should be routinely tested

Thyroid Function tests

in women with androgenic alopecia, an endocrinologic profile including serum testosterone, androstenedione and dehydro-epiandrosterone (DHEA) are done to rule out hyperandrogenism.

if discoid lupus erythematosus is suspected, antinuclear antibody tests are indicated.

Once the diagnosis is made, a comprehensive treatment plan can be charted out.