Metastatic pulmonary calcification as a rare complication of end-stage renal disease with coexistence of pulmonary metastases from renal cell carcinoma: case report and literature review

Purpose
We present a case of metastatic pulmonary calcification (MCP) in an asymptomatic patient with chronic kidney disease after renal transplantation and nephrectomy due to renal cancer. Chest computed tomography (CT) revealed bilateral, diffuse, centrilobular ground-glass opacities and heterogeneous, high-density areas distributed throughout the lungs, predominantly in the upper and middle lobes. Unusually, in our patient the metastatic calcification coexisted with pulmonary metastases from renal cell carcinoma associated with end-stage renal disease. To our knowledge, such coexistence has not been previously described.

Case report
CT, particularly high-resolution chest computed tomography (HRCT), plays an important role in detection and follow-up of MPC findings, which include ground-glass opacities and partially calcified nodules or consolidations, predominantly in the upper lung zones. Correct diagnosis is important because misdiagnosis may lead to improper or unnecessary treatment and/or procedures.

Conclusions
MPC is a rare condition that results from calcium deposition in the normal pulmonary parenchyma. MPC commonly occurs in patients with end-stage chronic kidney disease due to abnormalities in calcium and phosphate metabolism. It is worth pointing out that despite the fact that the condition is called metastatic, it is a relatively benign lung disease with a generally good long-term prognosis.