The coexistence of pemphigus and psoriasis: a systematic review and meta-analysis.

There is little consensus regarding the association between pemphigus and psoriasis. The aim of the current study is to synthesize existing data on the prevalence of psoriasis in patients with pemphigus and on the association between the two conditions. We performed a systematic review and meta-analysis of observational studies in Medline, Embase, and Web of Science (1900-2018). Reference lists of included studies were also searched for eligible studies. Quality of evidence was assessed using Newcastle-Ottawa scale (NOS). A meta-analysis was performed using random-effects models to estimate pooled prevalence rates and odds ratios (ORs) with 95% confidence intervals (CI). Subgroup and sensitivity analyses were also conducted. Twelve eligible studies comprising 12,238 patients with pemphigus were included in the quantitative synthesis. The overall random-effects pooled prevalence of psoriasis among patients with pemphigus was 2.4% (95% CI, 1.0-4.4) across all studies. The overall pooled multivariate OR for psoriasis in patients with pemphigus was significantly increased and estimated at 3.5 (95% CI, 1.6-7.6). In conclusion, a significant association was found between pemphigus and psoriasis. Physicians managing patients with pemphigus may be aware of this comorbidity. Further studies are warranted to establish the precise mechanisms underlying this relationship.