Advantages of metagenomic next-generation sequencing in the management of ANCA- associated vasculitis patients with pulmonary infections

Abstract

Abstract Background Pulmonary infection is one of the leading causes of death in patients with ANCA-associated vasculitis (AAV). Fiberoptic bronchoscopy and bronchoalveolar lavage fluid (BALF) assays are useful diagnostic methods. In addition to conventional microbiological tests (CMTs), metagenomic next-generation sequencing (mNGS) facilitates rapid and sensitive detection of various pathogens. We aimed to evaluate the advantages of additional BALF mNGS in the management of pulmonary infections in AAV patients. Methods Fourteen patients with active AAV and/or suspected infection whose BALF samples were tested by mNGS (BALF mNGS group) and 14 AAV patients whose BALF were tested by CMTs only (CMTs group) were retrospectively included in the study. The results of microbiological tests and adjustments of treatment upon BALF mNGS were described. The durations of antimicrobial treatment, ventilation and ICU stay as well as in-hospital mortality in patients were compared between the BALF mNGS group and the CMT group. Results A total of 64.3% (9/14) of patients in the BALF mNGS group had polymicrobial infections, including bacterium, fungus and virus. Patients in the BALF mNGS group received significantly shorter antibacterial treatment than those in the CMT group. Patients in the early BALF mNGS group (symptomatic infection duration before bronchoscopies < 5 days) received significantly shorter antibacterial and total antimicrobial treatments than those in the early CMT group. Patients with pulmonary infections in the BALF mNGS group received significantly shorter ventilation treatment than those in the CMT group. No deaths occurred in the early BALF mNGS group. Conclusions Compared with CMT alone, additional mNGS tests may shorten the duration of antimicrobial treatment and ventilation. mNGS might be further pursued as a routine approach for the management of active AAV patients with suspected pulmonary infections.