Haptoglobin is an independent marker for disease severity and risk for metabolic complications in hidradenitis suppurativa: A prospective study

Abstract

Background: Hidradenitis suppurativa (HS) is a chronic inflammatory disease that is highly correlated with obesity. Haptoglobin serum levels have recently been recognized as an important biomarker linking obesity with chronic inflammation.

Objective: To compare haptoglobin with previously proposed serum biomarkers for the determination of disease severity in HS patients. For this purpose, disease severity of HS patients was determined by a panel of clinical scores as well as several risk factors, such as weight and smoking habits.

Methods: A prospective, diagnostic accuracy study was performed at the International Centre for Hidradenitis suppurativa/Acne inversa Bochum (ICH). The study included a total of 263 patients, including 131 who had a confirmed diagnosis of HS in Hurley I (n = 16), II (n = 56) and III (n = 59) HS, and 132 healthy controls. The main outcome was to identify serological inflammatory markers for HS disease severity [severe (III) vs. moderate/mild (II/I)] as assessed by Hurley classification.

Results: The serum levels of acute phase proteins haptoglobin and CRP, as well as the number of neutrophils in peripheral blood, number of monocytes, the systemic immune-inflammation index and the pan-immune-inflammatory value correlated with disease severity according to established clinical scores (mHSS, SAHS, Hurley, DLQI). HS patients had significantly higher haptologlobin levels compared to healthy controls. Logistic regression analysis revealed haptoglobin as the only independent marker predicting severe HS.

Conclusion: In this prospective study, we discovered that the serum levels of the acute phase protein haptoglobin levels serve as an independent marker of disease severity in HS. While this presents the first study in the context of HS. Thus, the present data not only yield a highly promising serum marker to be further validated.