FRI0224 IDENTIFICATION OF RISK AND PROGNOSTIC FACTORS FOR POLYARTERITIS NODOSA PATIENTS WITH DIGITAL GANGRENE

Abstract

Background:Polyarteritis nodosa (PAN) is a segmental, necrotizing vascular disease that primarily impacts medium-sized muscle arteries. The estimated annual incidence of PAN is still lacking in China. Digital gangrene is an ischemic manifestation of the limb. However, the causes and the treatment methods vary from case to case, and the outcome is unpredictable. These features emphasize the need to identify measurable variables that accelerate digital gangrene development in PAN patients. However, little effort has been made to identify the clinical and laboratory factors that affect PAN patients with digital gangrene to anticipate their natural history and response to therapy.Objectives:Many patients with polyarteritis nodosa (PAN) complicated with digital gangrene have poor outcomes and related research information is limited. This study was carried out to identify the associated risk and prognostic factors.Methods:We conducted a retrospective study of 148 PAN patients admitted to Peking Union Medical College Hospital (PUMCH) from September 1986 to December 2018. The characteristics, therapeutic regimens, and outcome data for patients with and without gangrene were compared. The Kaplan–Meier method and Cox hazard regression model were used to evaluate the prognostic factors.Results:Forty-seven (31.8%) PAN patients had digital gangrene complications. The average age was 40.4±17.9 years and the average disease duration was 11 (4-27) months. The presence of digital gangrene was correlated with smoking history [odds ratio (OR), 4.27; 95% confidence interval (95% CI), 1.56-11.66] and eosinophil elevation (28.12; 10.30-76.8). Thirty-two (68.1%) gangrene patients received methylprednisolone pulse therapy and all of these patients were treated with cyclophosphamide. Nine patients suffered irreversible organ injury and two died. Disease duration ≥ 24 months and elevated serum C-reactive protein (CRP) were identified as hazardous factors for poor prognosis in patients with gangrene (P=0.003, HR=8.668, 95% CI 2.11, 35.55 andP=0.042, HR=27.062, 95% CI 1.13, 648.57, respectively).Conclusion:Smoking history and eosinophil elevation in PAN patients were more prone to digital gangrene and high serum CRP level predicted poor outcomes. PAN patients with smoking history and elevated eosinophils need to be seriously evaluated by clinicians. Furthermore, the CRP level should be efficiently controlled for good prognosis.