A case of bronchiolitis obliterans organizing pneumonia with renal dysfunction after renal transplantation

A 35-year-old male renal transplant patient was admitted with 3-week history of cough and myalgia after a 3-month post-transplantation. The patient's posttransplant course was uncomplicated and had no rejection. But on admission, the serum creatinine was 3.0 mg/dl and high-resolution computed tomography (HRCT) showed bilateral patchy densities and peripheral consolidations. Renal biopsy revealed mononuclear cell infiltration and non-specific tubular injury without evidence of rejection. An open lung biopsy was performed which showed multiple fibroblast plugs filling airspaces that were typical pathologic features of bronchiolitis obliterans with organizing pneumonia (BOOP). After prednisone therapy, the patient's pulmonary symptoms and radiographic findings rapidly recovered and serum creatinine also decreased from 3.0 to 2.1 mg/dl. Although the cause of renal dysfunction was not elucidated, we herein report a rare case of BOOP with renal dysfunction after renal transplantation.