Scalp Biopsies for Black Women with Hair Loss Often Lead to Change in Diagnosis

Keep a Low Threshold for Doing Scalp Biopsies in Black Women

Authors from Philadelphia set out to investigate the role of scalp biopsies in the diagnosis and management of Black women diagnosed with hair loss. The authors performed a retrospective chart review of all Black women over 18 years old diagnosed with hair loss by  general dermatologists from 2015 to 2020 in a single academic center.  

Of 420 patients in the study, 34.5% were diagnosed with more than one type of alopecia (multi- subtype alopecia), and 18.3% were not given a specific diagnosis. The other common diagnoses included alopecia areata (AA) (18%), traction alopecia (12.1%), and central centrifugal cicatricial alopecia (CCCA) (9.8%). Among those patients who were felt to have more than one diagnosis, traction alopecia was the most common (30.7%)  

 

Scalp Biopsies Changed the Diagnosis 70 % of the Time

About 40 of the 420 patients (9.5%) in the study underwent a scalp biopsy. The most common pre-biopsy diagnosis in this cohort was multi-subtype alopecia (50%), CCCA (15%), and no specific diagnosis (12.5%).

Biopsy led to a change in diagnosis 70.0% of the time!

The most common diagnosis became CCCA (27.5%) followed by other scarring alopecia subtypes, and the most common non-scarring alopecia became AA (15%).

Biopsies Reduce the Number of Patients with Multiple Diagnoses and Reduce Traction Alopecia

What was interesting is that after the biopsy the proportion of patients felt to have multiple diagnoses decreased from 50% to 5%. Furthermore, of all those who had no specific diagnosis before a biopsy, all had a diagnosis after the biopsy results came back. While traction alopecia was the most common diagnosis among patients who received more than one  alopecia diagnosis, post biopsy, its frequency was significantly reduced from 38% to 5%.  

For patients whose pre-biopsy diagnosis of traction alopecia was changed  as a result of doing the biopsy, the new diagnosis was LPP (70%), AA (20%), and psoriasis (10%). Over 75% of patients whose biopsy led to a change in the diagnosis had a change in their treatment plan.

Conclusions

This is a wonderful study. It reminds us just how important biopsies are in black women with hair loss. I’m of the opinion generally that a low threshold should exist for doing biopsies in black women presenting with hair loss – unless the diagnosis is extremely clear cut. We don’t need to do biopsies for most classic alopecia areata. We don’t need to do biopsies for most young patients under 25 with classic traction alopecia. But a low threshold needs to be put in place for many conditions. Without any doubt whatsoever, I perform biopsies for hair loss in  black women the most of any patient group.

In this study, scalp biopsies helped change the diagnosis in an incredibly high proportion of patients (70%). This is remarkable. Biopsies reduced the proportion of patients who end up being told them have “multiple hair loss issues” and decreased the number of patients who are told “it’s all due to traction alopecia.” It appears that traction alopecia is perhaps over diagnosed and too many black women are leaving the office with multiple incorrect diagnoses.

This study calls for a low threshold to do biopsies in black women. Certainly, we need to advanced our trichoscopy skills too but biopsies can be very helpful for evaluating hair loss in black women.

REFERENCE

Douglas A et al. Scalp Biopsy Influences Diagnostic Accuracy and Treatment in Black Women with Alopecia: A Retrospective Study. J Am Acad Dermatol . 2023 Jan 31;S0190-9622(23)00157-3.