More than half of patients with pyoderma gangrenosum present with a relevant underlying disease, according to a recent study, with inflammatory bowel disease and arthritis the most frequently associated diseases. Relative to the reported literature, the pooled prevalence of arthritis and hematological malignancies is lower, while the pooled prevalence of solid malignancies is higher. Researchers performed a systematic literature review and meta-analysis of observational studies dated from 1823–2017. The quality of evidence was assessed using a modified Newcastle-Ottawa Scale. A meta-analysis was performed using random-effects models to estimate pooled prevalence rates with 95% confidence intervals. 21 eligible studies comprising 2,611 patients with pyoderma gangrenosum were included in the quantitative synthesis. They found:
- The overall random-effects pooled prevalence of associated systemic diseases was 56.8%.
- The leading underlying disease was inflammatory bowel disease (17.6%), followed by arthritis (12.8%), hematological malignancies (8.9%), and solid malignancies (7.4%).
- In 16.3% of cases, the onset of pyoderma gangrenosum was attributed to the pathergy phenomenon.
Kridin K, Cohen AD, Amber KT. Underlying systemic diseases in pyoderma gangrenosum: A systematic review and meta-analysis. Am J Clin Dermatol. 2018;19(4):479-487. doi:10.1007/s40257-018-0356-7.