Effect of Sclerotherapy on Fistulas and Sinus Tracts in Hidradenitis Suppurativa

The clinical effect of the hypertonic saline treatment will be evaluated with Physician Assessments at week 2 (t=2), week four (t=4) and week 8 (t=8) and compared with the first visit (baseline) (t=0). If necessary, subjects will be eligible to receive another hypertonic saline injected in week 2 and/or week 4, with a maximum of three injections. Simultaneously improvement will be assessed by ultrasound if possible, using the Philips Lumify Ultrasound Device, and by patients using HS Improvement Assessments. Pain and stinging during treatment sessions will be monitored using numeric rating scales (NRS). For monitoring quality of life the DLQI will be used.