From the Guidelines
For someone experiencing acute hair loss, a comprehensive laboratory evaluation should include a complete blood count (CBC), iron studies, thyroid function tests, vitamin D levels, zinc levels, vitamin B12, folate, and a comprehensive metabolic panel to identify potential underlying causes. These tests are essential to assess for anemia, iron deficiency, thyroid disorders, and other nutritional deficiencies that can contribute to hair loss. Additional tests such as hormonal testing, including testosterone, DHEAS, and prolactin, may be warranted, particularly for women with signs of androgen excess 1. An antinuclear antibody test can help identify autoimmune conditions, while a scalp biopsy might be necessary in certain cases to determine the specific type of hair loss 1. Some key points to consider include:
- The role of micronutrients, such as vitamin D, in alopecia areata, with studies suggesting lower levels in patients with the condition 1
- The importance of iron status, with some studies suggesting an association between iron deficiency and hair loss, although the evidence is not conclusive 1
- The need for a comprehensive evaluation to identify underlying causes of hair loss, given the potential for nutritional deficiencies, hormonal imbalances, and systemic diseases to manifest as hair loss before other symptoms appear 1 It is crucial to prioritize these tests to identify potential underlying causes of hair loss and provide targeted treatment, potentially reversing the hair loss process and improving morbidity, mortality, and quality of life.
From the Research
Laboratory Tests for Acute Hair Loss
To diagnose the underlying cause of acute hair loss, several laboratory tests can be considered:
- Complete blood count (CBC) to rule out anemia or other blood-related disorders 2
- Ferritin level to assess iron stores, as iron deficiency has been linked to hair loss 3, 2
- Thyroid-stimulating hormone (TSH) level to evaluate thyroid function, as thyroid disorders can cause hair loss 2
- Vitamin D 25OH level to assess vitamin D status, as vitamin D deficiency has been associated with hair loss 2
- Erythrocyte zinc protoporphyrin concentration, transferrin concentration, serum iron concentration, and transferrin saturation to further evaluate iron deficiency 3
Additional Tests
Depending on the patient's medical history and physical examination findings, additional tests may be ordered:
- Scalp biopsy to confirm a diagnosis of cicatricial alopecia or to rule out other scalp conditions 4, 2
- Hair pull, hair tug, Hair Card, and hair mount to evaluate hair loss patterns and scalp condition 2
Considerations
When ordering laboratory tests, it is essential to consider the patient's overall health, medical history, and physical examination findings to determine the most appropriate tests and to avoid unnecessary testing 5, 4, 6