Color Doppler as a tool for correlating vascularization and pain in hidradenitis suppurativa lesions

Background: Hidradenitis suppurativa (HS) is a debilitating, chronic-relapsing, inflammatory skin disease of apocrine gland-bearing skin, presenting with nodules, abscesses, and fistulae. Ultrasound is used to classify HS lesions but evaluation of vascularization, related to tissue inflammation, needs Color Doppler. The aim was to correlate vascularization of HS lesions with patients’ reported pain. Methods: Vascularization was assessed with Hitachi Arietta V-70 sonographer according to a four-category system ranging from absent (0), minimal (1), moderate (2) vascularization, and detectable vascular flow (3). Pain was scored with Numeric Rating Scale (NRS) from 0 to 10. Results: Twenty-four patients were included, 13 men (54.2%) and 11 women with mean age of 37.2 (range: 19-61 years). Sixty-nine HS lesions were studied: none of the lesions with absence of vascularization was painful. Lesions with minimal vascularization had a mean NRS value of 3.1 (range: 0 to 7; standard deviation [SD]: 1.6). Lesions with moderate vascularization had a mean NRS value of 6.4 (range: 4-8; SD: 1.4). Lesions with intense vascular flow had a mean NRS value of 7.8 (range: 5-9; SD: 1.7). Correlation Spearman's rank coefficient calculated between the class of vascularization and the mean NRS value was 0.98, supporting high correlation between intensity of vascularization and local pain. Conclusion: The present study is the first one demonstrating correlation between vascularization of HS lesions assessed with Color Doppler and local pain. Color Doppler may be a dynamic diagnostic tool that can address the therapeutic approach and assess response to treatment in HS.