Infectious complications in adult patients with idiopathic minimal change nephrotic syndrome undergoing immunosuppressive therapy.

Background: Patients with idiopathic minimal change nephrotic syndrome (MCNS) undergoing immunosuppressive therapy are susceptible to infectious complications. Study specifically focusing on adult population's infectious complications is lacking.

Methods: We retrospectively collected 101 adult patients with biopsy-proven idiopathic MCNS and analysed for the infectious complications. Published literatures were also reviewed aiming to evaluate the feasibility of prophylactic antibiotic treatment.

Results: Infectious complications developed in 17 of 101 (16.8%) patients, with pneumonia (n = 4), cellulitis/fasciitis (n = 4) and urinary tract infection (UTI) (n = 4) being the dominant diseases, and Gram-negative bacilli the main cause. AKI stage ≥2 (Hazard ratio = 6.1; 95% CI: 1.2-31.9, p = 0.031) and non-remission by treatment (Hazard ratio = 4.4; 95% CI: 1.2-15.6, p = .023) were the two independent risk factors relevant to developing infectious complications. Review of 16 published literatures and our data showed that even no prophylactic antibiotic therapy, only one case of Pneumocystis jirovecii pneumonia developed among the 1787 accumulative cases of MCNS. In contrast, 16 (44%) of acute flare cases were reported among the 36 patients with positive hepatitis B surface antigen that did not receive antiviral prophylactic therapy.

Conclusions: Advanced acute kidney injury and non-remission by treatment are the risk factors toward developing infectious complications in adult MCNS undergoing immunosuppressive therapy. It appears unnecessary to use prophylactic antibiotic for Pneumocystis jirovecii pneumonia or other bacterial infections, while screening and prophylactic therapy for hepatitis B and latent tuberculosis are critical for patients in prevalent area.