A 66-year-old male treated with everolimus for renal cell carcinoma developed exertional dyspnea. Chest computed tomography revealed diffuse interstitial shadows on both lungs. Bronchoalveolar lavage and the drug-induced lymphocyte stimulation test confirmed the diagnosis of drug-induced interstitial lung disease due to everolimus therapy. However, discontinuation of everolimus in combination with corticosteroid therapy did not prevent disease progression. On the basis of a PCR assay for Pneumocystis jirovecii and elevated β-D-glucan levels, trimethoprim-sulfamethoxazole was administered immediately, resulting in a dramatic improvement. This case demonstrated that pneumocystis pneumonia should always be considered and treated during everolimus therapy, even when drug-induced interstitial lung disease is suspected.
Keywords: Bronchoalveolar lavage; Drug-induced interstitial lung disease; Everolimus; Pneumocystis jirovecii.