Ultrasonography in the pathway to an optimal standard of care of hidradenitis suppurativa: the Italian Ultrasound Working Group experience

Background: Ultrasound (US) is a real-time non-invasive technique that has been demonstrated to support an early diagnosis and a more precise assessment of hidradenitis suppurativa (HS). Objectives: To compare the clinical and US evaluation of a series of HS patients. Methods: 434 HS patients (259 F, 175 M; mean age 33.82 ±13.31 years) observed across 19 Italian dermatology centres [members of the Italian Ultrasound Working Group (IUWG)] were enrolled in a retrospective study. Clinical staging was obtained by the Hidradenitis Suppurativa Physician's Global Assessment score (HS-PGA), while the ultrasonographic staging was determined by the US HS-PGA, based on the same scores as clinical HS-PGA but performed with the aid of US. Results: At the end of the study, the mean clinical and US HS-PGA scores were 2.70 and 2.92, respectively. Direct comparison of clinical and ultrasonographic assessment revealed that a higher proportion of patients was classified as having moderate and very severe disease by US. In particular, 117 patients (26.96%) had a worse classification by US HS-PGA compared to clinical assessment. Conclusion: Our findings confirm that the use of clinical grading only to assess HS severity may underestimate the real disease severity. US examination can be considered an essential non-invasive imaging tool available to dermatologists for a more accurate diagnosis, staging, treatment planning and monitoring of HS and should be included in the pathway to an optimal standard of care of HS.