I am experiencing severe and non-stop hair loss for the last 6 months. I am confused about what blood tests I am supposed to get? What is the standard panel that my doctor should be ordering?
Thanks for the question. This is an important question that is too often overlooked. In general terms, blood tests are required for most women with hair loss. For men, they are usually not. However, each patient's hair loss needs to be reviewed on a case by case basis as there is not simple rule about what tests are needed. The exact tests that are needed depends on the patient’s history and their examination findings.
Women with hair loss
For women, I'll not go without blood tests. Blood tests are required for all women with hair loss. Blood tests are mandatory. Simply put there are so many mimickers of female hair loss and diagnosing female hair loss is far more complex than diagnosing hair loss in men. I will order tests for basic blood counts (CBC), thyroid (TSH) and iron (ferritin) in all women with hair loss.
For young women with acne or increased facial hair, a tests for DHEAS (hormones from the adrenal gland), androstenedione (hormones from the ovaries) as well as free and total testosterone and sex hormone binding globulin (SHBG) are ordered. Women with irregular menstrual cycles may require blood tests to evaluate polycystic ovarian syndrome including tests for LH, FSH, DHEAS, androstenedione, prolactin, estrogen, free and total testosterone and 17 hydroxyprogesterone (17OHP) and sex hormone binding globulin (SHBG). Blood sugars may also be checked.
Women with dietary restriction may also have zinc levels checked and a few other minerals as well (i.e. selenium). Sometimes vitamin D is checked depending on where the patient lives. Women with low ferritin and hemoblogin may, in some situations, benefit from celiac screening before consideration of further testing.
Similar to the discussion for men, women with potential autoimmune causes of hair loss require comprehensive evaluation including complete blood counts (CBC), thyroid (TSH), iron (ferritin), ESR, ANA, B12.
This is typically the extent of tests for most. However, should there by any suspicion of a larger systemic issue, liver tests (AST, ALT, bilirubin) might be ordered and kidney function tests (including creatinine and urinalysis) might be considered). One must always consider syphilis screening in all patients as rates are increasing worldwide.
Men with hair loss
For men with male pattern balding (androgenetic alopecia), blood tests are not needed most of the time. I may check 25 hydroxyvitamin D levels depending on the background of the patent and where in the world they live. For young males with male pattern balding, I often test cholesterol level as there may an increased risk of lipid abnormalities in this patient group. This is an important and poorly recognized issue and I’ve written about it in previous articles:
For men with hair loss due to various autoimmune causes (such as alopecia areata or lichen planopilaris) I often check blood tests such as basic blood counts (CBC) , thyroid (TSH), iron status (ferritin), ANA, B12, ESR. In some situations, I'll consider a free and total testosterone.
This is typically the extent of tests for most. However, should there by any suspicion of a larger systemic issue, liver tests (AST, ALT, bilirubin) might be ordered and kidney function tests (including creatinine and urinalysis) might be considered). Men with nutritional issues and weight loss, require a far more involved work up including consideration for zinc, selenium screening. Men with low ferritin and hemoglogin may warrant celiac screening before consideration of further testing. One must always consider syphilis screening in all patients as rates are increasing worldwide.
Dozens of other tests available.
There are dozens of other tests available but most of the time they are inappropriate. I see serum iron and serum TIBC ordered inappropriately much of the time. I also see free T3 and free T4 ordered in appropriately as well. There may be a role for some patients but not most.
In other situations a variety of tests can be considered. In a patient with a positive ANA result, anti-double stranded DNA might be considered (along with urinalysis, creatinine, liver function etc). Patients with suspected sarcoidosis may benefit from serum ACE. HIV testing may be appropriate in some situations as well. There are dozens of other sophisticated tests that can be ordered but are generally inappropriate to order as basic screening tests.
All in all, there is no standard template for ordering blood tests for a patient with hair loss. The tests that need to be ordered are determined once the patient’s story is fully understood and their scalps are examined. If certain tests are abnormal, additional tests may then be considered.