Hyperbaric Oxygen Therapy for Pyoderma Gangrenosum

Rationale: Pyoderma gangrenosum (PG) is a rare auto-inflammatory neutrophilic dermatosis characterized by a spectrum of clinical presentations with variable courses. Diagnosis and management are challenging in PG. Treatment, including systemic prednisone and anti-TNF therapy, is directed towards reducing pain and associated inflammation that leads to ulceration. Positive effects of hyperbaric oxygen (HBO) therapy have been reported in small case series. Objective: To investigate the therapeutic efficacy of hyperbaric oxygen on top of standard wound care and regular anti-inflammatory treatment in patients with pyoderma gangrenosum wounds. Study design: Prospective cohort study with a follow-up to one year. Study population: 15 adult patients with pyoderma gangrenosum refractory to standard-prednisone or anti-TNF therapy will be included for hyperbaric oxygen therapy. Patients with pyoderma gangrenosum that are eligible but reject hyperbaric oxygen treatment will serve as controls. In total the investigators will include 30 patients. Intervention (if applicable): 30 sessions of HBO therapy will be applied on top of regular wound care and systemic anti-inflammatory treatment. Controls will be treated with regular wound care and anti-inflammatory treatment. Main study parameters/endpoints: Wound healing time (time to wound closure). PG wounds will be measured at baseline using a validated, objective 3D photographical wound measurement tool, and again after 3 and 6 weeks at the end of HBO treatment and after 3 months. Patients will take weekly photographs at home using a 2D validated measurement tool of the wounds. Secondary parameters: Alteration in the expression of markers of inflammation by micro-biopsies of wound edges, non-invasive mitochondrial O2 measurements at wound edges, blood neutrophil count and patient-reported outcomes like WOUND-Q, pain on NR scale and treatment satisfaction scores. Assessment concerning laboratory findings will be done at baseline