Clinicopathological features and prognosis of pyoderma gangrenosum in Korea: A single centre, retrospective, observational study over 20 years.

BACKGROUND

Pyoderma gangrenosum is a rare autoinflammatory neutrophilic dermatosis that rapidly evolves. However, little is known about the clinicopathological features and prognosis of pyoderma gangrenosum.

AIMS: We aimed to document clinicopathologic and prognostic data of the patients with pyoderma gangrenosum.

METHODS

In this retrospective observational study, we reviewed case records of patients diagnosed with pyoderma gangrenosum between 1999-2019.

RESULTS

Fifty-three patients were identified by reviewing medical records for skin biopsy; of these, 37 were men and 16 were women. Mean age at onset was 43.3 ± 18.5 years. The most frequently affected area was the lower extremities (60.4%), followed by the head and neck (17.0%). The most common subtype was ulcerative (47.2%), followed by bullous (22.6%). 30 cases had underlying diseases and the most common were malignancy (24.5%), followed by inflammatory bowel diseases (18.9%). The proportion of cases with history of trauma were significantly higher in post-operative type (100%) as compared to the bullous type (8.3%). Histologic features of granulation tissue were frequently found in post-operative type (66.7%) and bullous type (58.3%). Granulomas were predominantly found in bullous type (58.3%). Age <60 years appeared to be significantly associated with multiple lesions. Partial-to-complete remission was observed in 40 cases (75.5%). Nine (17.0%) cases experienced recurrence with a median progression-free period of six months (interquartile range of 3.0-9.0 months). Cases with underlying hematologic disorders and the bullous subtype were significantly associated with early recurrence.

LIMITATIONS: This study was a single-centre study with a retrospective design.

CONCLUSION

Pyoderma gangrenosum appears to have ethnic differences. Underlying haematologic disorders and bullous subtype have a worse prognosis. However, the type of histopathology did not correlate with the clinical outcome of pyoderma gangrenosum.