Severe infections in systemic necrotizing vasculitis

Infections in patients with systemic vasculitis represent one of the main causes of mortality. Corticosteroid use, immunosuppressive therapy, age, associated organic involvement and dialysis dependence are risk factors of infection.

Objectives

To determine the prevalence of severe infection and associated factors in patients diagnosed with ANCA-associated vasculitis (AAV) and Polyarteritis Nodosa (PAN).

Methods

retrospective study was conduced in a single rheumatology center (2000–2018). We included patients diagnosed with AAV (Granulomatosis with Polyangiitis (GPA), Eosinophilic Granulomatosis with Polyangiitis (EGPA) and Microscopic Polyangiitis (PAM) and Polyarteritis nodosa (PAN). Serious infectious events requiring hospitalisation or prolonged antibiotic/antiviral treatment, recurrent infection of Herpes Zoster Virus or opportunistic infections were evaluated. Sites of infection, isolated microorganisms and mortality related were analyzed.

Results

105 patients were analyzed, follow-up time median 18 m, 58.7% were women and median age was 52 years. Types of vasculitis: 41.9% PAM, 16.2% EPGA, 40% GPA, 1.9% PAN. Constitutional, pulmonary, renal and otorhinolaryngology manifestations were the most frequent.

Prevalence of infection

34.2%, with a median of 3 months from diagnosis of vasculitis to the infectious event. Low respiratory tract (42.8%), sepsis (31.4%), and urinary tract (14.3%) were the most common sites of infections. Bacterial aetiology was the most prevalent (67.7%). Mortality at the first event was 14.3% and a 72.2% of patients were in the induction phase of treatment.

Infectious events were significantly associated with age > 65 years (p = 0.030), presence of lung (p = 0.016) and renal involvement (p = 0.001), BVASv3 > 15, mortality (p = 0.0002).

Conclusions

The prevalence of infection was 34.2%. Lower airway infections, septicemia and urinary tract infections were the most prevalent. Infections were associated with renal and pulmonary involvement, age older than 65 years and score BVAS > 15. Severe infections were associated with mortality, especially in elderly patients.