Clinical manifestations, prognostic impact, and relapse in polyarteritis nodosa: a systematic review and meta-analysis.

Polyarteritis Nodosa is a rare necrotizing vasculitis with a broad and variable clinical presentation, driven by its ability to affect multiple organs and systems. This heterogeneity influences disease severity, relapse risk, and mortality, highlighting the prognostic importance of its diverse manifestations. This systematic review and meta-analysis synthesize the available evidence to define the clinical profile of Polyarteritis Nodosa and highlight key prognostic factors. A systematic search of electronic databases was conducted to identify studies reporting clinical manifestations and outcomes of patients diagnosed with Polyarteritis Nodosa. Pooled prevalence summary estimates were calculated using R software, including subgroup analyses by age group. Case Fatality Rate was calculated to determine the clinical severity of the manifestations. Across adult and pediatric groups, the most common manifestations were fever (~ 52%), myalgia (~ 53%), and cutaneous involvement (~ 56%). Age significantly moderated the prevalence of fever, arthralgia, hypertension, and peripheral neuropathy. Several symptoms were frequently observed among patients who experienced relapse, particularly cutaneous involvement (~ 66%) and myalgia (~ 64%). While cardiac involvement was associated with higher case fatality, gastrointestinal manifestations accounted for a greater proportion of reported deaths overall. Total mortality was approximately 13%, relapse occurred in about 27% of patients, while roughly 65% of patients achieved remission. This systematic review with meta-analysis provides crucial information to clinical physicians, regarding the clinical profile and the prognostic factors of Polyarteritis Nodosa. Thus, these insights could guide management strategies and increase the survival and remission rate of these patients. PROSPERO: https://www.crd.york.ac.uk/PROSPERO/view/CRD420251249274 .