From the Guidelines
Laboratory tests for alopecia should prioritize non-invasive methods such as trichoscopy, hair counts, and hair diameter measurement to assess treatment response and guide management decisions. When evaluating alopecia, it is essential to consider the most recent and highest quality evidence, which suggests that a combination of non-invasive tests can provide valuable information on hair growth and treatment response 1.
Key Tests for Alopecia
- Trichoscopy: involves using a specialized magnifying device to examine the scalp and hair follicles in detail, helping identify signs of hair thinning and miniaturization 1.
- Hair counts and hair diameter measurement: provide objective data on treatment response and can be used to assess improvements in hair growth 1.
- Patient self-assessment questionnaires: allow patients to evaluate their own hair growth and satisfaction with treatment, providing valuable subjective data 1.
- Global Physician Assessment (GPA): offers an overall evaluation of treatment response and can be used in conjunction with other tests to guide management decisions 1. In some cases, a scalp biopsy may be necessary to examine the hair follicles under a microscope, particularly when the diagnosis is unclear or when scarring alopecia is suspected 1.
Additional Considerations
- Photography, including before-and-after photos, can be used to visually compare treatment response and evaluate improvements in hair growth 1.
- The pull test can assess active shedding, while trichogram analysis can provide objective data on hair density, diameter, and terminal/vellus ratio 1. By prioritizing these non-invasive tests and considering the individual patient's needs and circumstances, healthcare providers can develop effective treatment plans that improve outcomes and quality of life for patients with alopecia.
From the Research
Lab Tests for Alopecia
Lab tests for alopecia are essential in determining the underlying cause of hair loss. Some of the key lab tests include:
- Blood tests to check for iron deficiency, autoimmune diseases, and thyroid disorders 2
- Hemoglobin (Hb) test to check for anemia, which can be a cause of hair loss 2
- Ferritin test to check for iron deficiency, which is a common cause of hair loss in women 2
- Zinc (Zn) test to check for zinc deficiency, which can also cause hair loss 2
- Autoimmune and thyroid profiles to check for underlying autoimmune or thyroid disorders that can cause hair loss 2, 3
Importance of Lab Tests
Lab tests are crucial in diagnosing the underlying cause of alopecia, as the condition can have various etiologies, including:
- Nutrient deficiencies, such as iron deficiency 2
- Autoimmune diseases, such as alopecia areata 3, 4
- Thyroid disorders, such as hypothyroidism or hyperthyroidism 2, 3
- Psychological stress, which can cause telogen effluvium 2, 3
- Systemic diseases, such as malnutrition or endocrine diseases 3, 5
Diagnostic Approach
A comprehensive diagnostic approach is necessary to evaluate patients with alopecia, including: