Infectious profile in inpatients with ANCA-associated vasculitis: a single-center retrospective study from Southern China

Objectives Infection is a common complication in ANCA-associated vasculitis (AAV). The study goal was to investigate the infectious profile in patients with AAV from Southern China. Methods A retrospective study was performed on the inpatients from the First Affiliated Hospital of Sun Yat-sen University from 2012 to 2017. Demographic and clinical characteristics were recorded. Results A total of 132 AAV inpatients with 174 episodes of infection (prevalence, 63.8%) were included. Lung was the most commonly involved. Ninety-six (72.7%) patients developed infection during the first 6 months after AAV diagnosis. Bacteria (75.9%) were the prominent microbes. Gram-negative bacteria were predominant (71.4%). The most frequently isolated bacteria were P. aeruginosa (16.7%) and A. baumannii (16.7%). Mixed infection accounted for 14.9% of the episodes, while fungal infection accounted for 6.3%. Mortality rate was 12.9% (17/132). Six deceased patients (46.2%) were infected with multiple pathogens. In multivariate analysis, smoking (odds ratio (OR) 2.38, 95% confidence interval (CI) 1.13–5.03, P = 0.02), kidney involvement (OR 2.56, 95% CI 1.11–5.88, P = 0.03), lymphopenia (OR 2.33, 95% CI 1.20–4.55, P = 0.01), and dialysis (OR 3.06, 95% CI 1.14–8.20, P = 0.03) were associated with infection in patients with AAV. Conclusions Bacteria, especially Gram-negative bacteria, were the major pathogens in Chinese AAV patients. Mixed infection was a great threat to death. Infection tended to develop within the 6 months after AAV diagnosis. Smoking, kidney involvement, dialysis, and lymphopenia increased the risk of infection in patients with AAV. Key Points • Infection tended to develop within the 6 months after AAV diagnosis . • Gram-negative bacteria were the leading pathogens . • Smoking, kidney involvement, dialysis, and lymphopenia increased the risk of infection in patients with AAV .