Laboratory Tests and Ancillaries
Androgenic Alopecia in Males/Females
It must be noted that diagnostic tests are rarely indicated for
MPHL and females with normal menstrual cycles. If there is evidence of androgen
excess in FPHL, total testosterone, free testosterone, dehydroepiandrosterone
sulfate (DHEAS), prolactin levels can be considered. If without evidence of androgen excess, thyroid
disease, syphilis, iron deficiency, and systemic lupus erythematosus (SLE) are
ruled out as possible cause of hair loss. Biopsy is sometimes necessary at times for FPHL to exclude
chronic telogen effluvium, diffuse alopecia areata or cicatricial hair loss. Trichoscopy, also known as dermoscopy, should
be considered in doubtful cases. In trichoscopy, features typical for
androgenic alopecia include vellus hairs >10%, increased percentage of
follicular units with only one hair shaft, hair shaft thickness heterogeneity
of ≥20%, yellow dots, perifollicular discoloration, empty follicles, and circle
hair and honeycomb pigment pattern.
Alopecia Areata
Trichoscopy (dermoscopy) may be helpful for visualizing findings
consistent with alopecia areata. Features typical of alopecia areata include
short vellus hairs, black dots, yellow dots, tapering hairs and broken hairs. Patch biopsy of the scalp may be performed
in rare, difficult cases if diffuse alopecia reata is suspected. Thyroid stimulating hormone (TSH)
level determination is routinely performed by many physicians to rule out any
related thyroid abnormality. A trichogram may be considered as a complementary tool for
clinical assessment, diagnosis and monitoring response to treatment. Laboratory
exams such as blood count, thyroid values, liver and kidney function tests, ANA
titer may be carried out.
Alopecia_Diagnostics
Imaging
Medical photography is recommended to be done in alopecia areata for a baseline.