Anti-Glomerular Basement Membrane Nephritis Potentially Induced by Nebulized Tobramycin Inhalation

Objective: To describe a case of anti-glomerular basement membrane (GBM) nephritis that occurred shortly after initiation of nebulized tobramycin (TOB) therapy using intravenous solution, suggesting an association with the inhalation therapy and the disease onset. Background: With the emergence of antimicrobial resistance, clinical importance of aminoglycosides that usually remain susceptibility against gram-negative organisms is increasingly acknowledged. Despite the growing number of evidence supporting the effectiveness of aminoglycoside inhalation therapy for respiratory tract infections, its clinical application has yet to be widely approved by Japanese health insurance. Case Presentation: A 79-year-old Japanese woman had developed amyotrophic lateral sclerosis and experienced recurrent pneumonia mainly caused by Pseudomonas aeruginosa, which required monthly treatments with broad-spectrum antibiotics. Owing to the limited approval, we had no choice but to use intravenous TOB solution for inhalation therapy as an off-label use under an endorsement of the Institutional Review Board of the hospital. Although the repeated pneumonia subsided, the patient subsequently needed immunosuppressive therapy along with plasma exchanges for the treatment of anti-GBM nephritis. Conclusion: Although this off-label use of intravenous solutions is common in both clinical and research purposes, our case raised an issue that its safety needs to be re-evaluated.