TACROLIMUS-INDUCED LUNG INJURY

Abstract

TOPIC: Diffuse Lung Disease TYPE: Fellow Case Reports INTRODUCTION: Tacrolimus is commonly used for immunosuppression after solid-organ transplant to prevent organ rejection. Tacrolimus has a wide range of adverse effects, including secondary infections, renal failure, hyperglycemia, and weight gain, when used in combination with other immunosuppression medications. However, association with diffuse lung disease is quite rare. We present a case of diffuse lung injury associated with tacrolimus. CASE PRESENTATION: A 56-year-old Caucasian man with a past medical history of hypertension, diabetes, morbid obesity, renal transplant on tacrolimus and mycophenolate, and localized renal cell carcinoma with nephrectomy was transferred to our institution for evaluation of suspected non-small cell lung cancer (NSCLC). A few weeks prior to the current presentation, the patient was diagnosed and treated for community-acquired pneumonia with oral antibiotics. Follow-up imaging, with CT Chest and subsequent PET CT, revealed diffuse interstitial changes with multiple small pulmonary nodules without increased metabolic activity concerning for lymphangitic carcinomatosis or atypical infection. During PET CT, the patient became hypoxic and was admitted. Bronchoscopy with brush biopsy and BAL demonstrated atypical cells concerning for NSCLC, and the patient was transferred to our institution for further evaluation. Due to inconclusive pathology report from prior bronchoscopy, persistent hypoxia, and dyspnea on exertion, the patient underwent repeat bronchoscopy with endobronchial ultrasound-guided biopsy, BAL, and trans-bronchial biopsies, which was negative for malignancy. Extensive microbiologic workup for viral, bacterial, and fungal organisms remained negative. BAL differential showed significant eosinophilia of 15%, and transbronchial biopsy showed acute on chronic inflammation. Drug toxicity secondary to tacrolimus was presumed to be the primary culprit. The patient was started on prednisone therapy and discharged. On outpatient follow-up six weeks later, the patient had resolution of dyspnea, and repeat imaging demonstrated complete resolution of interstitial opacities. Tacrolimus was discontinued indefinitely. DISCUSSION: Tacrolimus is commonly used for immunosuppression after solid organ transplantation to prevent organ rejection. The association of Tacrolimus with interstitial lung disease is quite rare and previously described in a case series of rheumatoid arthritis patients. To the best of our knowledge, this is the first description of tacrolimus-induced interstitial lung disease in renal transplant patients. CONCLUSIONS: Tacrolimus-associated diffuse lung disease, although rare, should be considered in patients presenting with diffuse infiltrates while on this therapy, after appropriate work up to exclude infections. REFERENCE #1: M. Schwaiblmair, W. Behr, T. Haeckel, B. Markl, W. Foerg, and T. Berghaus, "Drug induced instertial lung disease," Open Respiratory Medicine Journal, vol. 6, no. 1, pp. 63-74, 2012 REFERENCE #2: Allen JN, Davis WB, Pacht ER. "Diagnostic significance of increased bronchoalveolar lavage fluid eosinophils." Am Rev Respir Dis. 1990 Sept;142(3):642-7, doi:10.1164/ajrccm/142.3.642. PMID: 2389917. REFERENCE #3: Koike R, Tanaka M, Komano Y, Sakai F, Sugiyama H, Nanki T, Ide H, Jodo S, Katayama K, Matsushima H, Miwa Y. Tacrolimus-induced pulmonary injury in rheumatoid arthritis patients. Pulmonary pharmacology & therapeutics. 2011 Aug 1;24(4):401-6. DISCLOSURES: No relevant relationships by Sarenthia Epps, source=Web Response no disclosure on file for Anand Venkata