How do we distinguish DUPA from CTE?
Diffuse unpatterned alopecia (DUPA) can generally be differentiated from chronic telogen effluvium (CTE) by careful review of the patient's history, and examination of the scalp using dermoscopy. Rarely a biopsy can be confirmatory but usually this is not needed.
On history, patients with DUPA report diffuse thinning. They usually don't have all that much in terms of increased shedding. Typically, the hair loss is first noticed between age 15-24. Examination of the scalp shows variation in the sizes of follicles. We call this 'anisotrichosis'. Some hairs are thick and some are thin. The miniaturization occurs all over the scalp. A biopsy shows a terminal to vellus ratio of much less than 4:1.
In contrast to DUPA, patients with true CTE are usually a bit older when they first notice hair loss, often 35-60. Their stories are markes by concerns about massive shedding that comes and goes, some weeks good and some weeks bad. Patients with CTE don't usually look like they have hair loss to others whereas patients with DUPA often do look like they have hair loss. In CTE, examination shows terminal thick hairs. The temples may or may not show recession but often do in the setting of CTE. A biopsy shows T: V ratios that are high - and ratios 8:1 or higher are suggestive of CTE (compared to less than 4:1 for DUPA).
In summary, DUPA and CTE can usually be easily differentiated with careful examination and review of the patient's story.
Dr. Jeff Donovan is a Canadian and US board certified dermatologist specializing exclusively in hair loss. To schedule a consultation, please call the Whistler office at 604.283.1887