Clinical signs and laboratory tests for the differential diagnosis ofandrogenic and post-COVID-19 alopecia in women

Abstract

Background. The most common type of pathological hair loss in women is androgenetic alopecia (AGA), arises due to hormonal and micronutrient imbalances. During the COVID-19 epidemic, there has been an increase in the number of female patients with alopecia as a complication, with some individuals experiencing alopecia the sole indication of asymptomatic COVID-19. Aims. The search for objective criteria for the differential diagnosis of AGA and post-COVID alopecia in women based on trichological and laboratory markers. Methods. The including criteria for AGA were elevated dihydrotestosterone (DHT) levels, for the post-COVID alopecia — a diagnosis of COVID-19 using RT-PCR and the presence of alopecia symptoms for both conditions. Quantitative characteristics of hairs were analyzed based on trichogram and phototrichogram. Levels of DHT, vitamins B9, B12, D, E, Ca, Fe, Mg, Se, Cu, and Zn were evaluated in serum. CART algorithm (Classification and Regression Trees) was applied to determine criteria to differentiate between patients with androgenetic and post-COVID alopecia. Results. Analysis revealed the change in telogen/anagen ratio in the androgen-dependent zone in in AGA, and in androgen-dependent (parietal) area in post-COVID. Notably, patients with post-COVID alopecia exhibited elevated DHT levels compared to reference, with no significant difference in comparison to AGA. There was a significant 46.4% reduction in Cu content (p = 0.006) alongside an 24.7% increase in Se levels (p = 0.003) in post-COVID alopecia. Conclusion. The percent of telogen hair and serum Se level as the objective criteria for the differential diagnosis of AGA and post-COVID alopecia in women are presented.