Developing multiple lung nodules in a renal transplant recipient with tuberous sclerosis who had undergone bilateral nephrectomy due to renal cell carcinomas.

A 38-year-old woman, who had been diagnosed as having tuberous sclerosis (TSC), incidentally presented with asymptomatic multiple pulmonary nodules detected by computed tomography during immunosuppressive therapy for 6 years after renal transplantation. The recurrence of renal cell carcinoma (RCC) was suspected because the patient underwent bilateral nephrectomies due to RCC in dialysis kidneys before transplantation. However, the lung biopsy specimen was diagnosed as multifocal micronodular pneumocyte hyperplasia (MMPH), which is an extremely rare benign lung involvement in TSC. It is necessary to consider MMPH in the differential diagnosis when lung nodules are observed in TSC patients.