Amyloidosis in hidradenitis suppurativa: a cross-sectional study and review of the literature.

BACKGROUND

Coexistence of hidradenitis suppurativa (HS) and amyloidosis has been anecdotally described, but the association between these conditions is yet to be firmly established.

AIM: To study the association between HS and amyloidosis using a large-scale computerized database, and to perform a literature review to characterize all reported patients with coexistent HS and amyloidosis.

METHODS

A cross-sectional study was conducted comparing the prevalence of amyloidosis among patients with HS and age-, sex- and ethnicity-matched healthy controls (HCs). Additionally, a review of literature was performed to summarize all reported cases with a dual diagnosis of both conditions.

RESULTS

In total, 4417 patients with HS and 22 085 controls were included in the study. The prevalence of amyloidosis was increased in patients with HS compared with the HC group [n = 7 (0.2%) vs. n = 2 (0.0%), respectively; OR = 17.5; 95% CI 3.6-84.4; P < 0.001]. In a multivariate analysis, HS was still associated with amyloidosis (OR = 11.2; 95% CI 1.3-94.5; P = 0.03). The literature review identified nine patients who developed amyloidosis during the course of HS, with 44.4% eventually having renal failure. ‬Favourable outcomes were reported in patients managed by tumour necrosis factor (TNF)-α inhibitors.

CONCLUSION

This study establishes the association between HS and amyloidosis. Screening for amyloidosis may be considered in patients with HS with a relevant clinical picture, mainly proteinuria. TNF-α inhibitors may be preferred in patients with a dual diagnosis of these conditions.