Metastatic pulmonary calcification in a renal transplant recipient

Abstract

Metastatic pulmonary calcification (MPC) is a metabolic disorder characterized by an ectopic deposition of calcium in the lung parenchyma, prevalent in patients with chronic kidney disease. A combination of parenchymal lung abnormalities on high resolution chest computed tomography (CT) and pulmonary radiotracer uptake in ^99mTc-methyl diphosphate (MDP) bone scintigraphy can establish diagnosis of MPC. We herein present a case of MPC with documented stability of chest CT abnormalities after renal transplant. We also describe novel findings of diffuse pulmonary uptake of ¹⁸F-sodium fluoride, a calcium-avid radiotracer, in positron emission tomography (PET)/CT performed in the same patient.

Keywords: Dialysis; Metastatic pulmonary calcification; Positron emission tomography; Renal transplant.

Fig. 1

Computed tomography pulmonary angiography during hospitalization with diffuse bilateral ground-glass opacities, small bilateral pleural effusions, mediastinal and right hilar lymphadenopathy, and stable osseous metastatic disease.

Fig. 2

(A) Chest computed tomography (CT) three years earlier showing the centrilobular nodule-like portion of the ground-glass opacities (GGOs); (B) Chest CT 2 months after hospitalization with improvement of diffuse GGOs and chest lymphadenopathy.

Fig. 3

(A) ^99mTc-methyl diphosphate bone scintigraphy three years earlier with diffuse radiotracer uptake within the bilateral lungs and multiple ribs; (B–D) ¹⁸F-sodium fluoride positron emission tomography/computed tomography five years earlier with diffuse pulmonary uptake corresponding to the upper lobe predominant ground-glass opacities, as well as multiple radiotracer uptake to bones.

Fig. 4

(A, B) Bronchoscopy with nodular while lesions.