Renal osteodystrophy is a skeletal manifestation of chronic kidney disease (CKD) and part of the CKD–Mineral Bone Disorder (CKD–MBD) spectrum. Diffuse osteosclerosis is a rare presentation and may be mistaken for skeletal metastasis, particularly in oncologic patients. We report a 65-year-old male with a history of high-grade papillary urothelial carcinoma, status post-radical cystectomy and ileal conduit. On follow-up, he developed stage IV CKD and presented with back pain. 18F-FDG PET-CT revealed diffuse skeletal osteosclerosis without FDG-uptake. Laboratory tests showed elevated parathyroid hormone with normal calcium, phosphate, and vitamin D levels. Tc-99m Sestamibi parathyroid scintigraphy ruled out parathyroid adenoma. A diagnosis of renal osteodystrophy due to secondary hyperparathyroidism was made. This case underscores the need to differentiate metabolic bone disease from metastases in cancer patients, avoiding unnecessary treatment.
Kolur et al. (Tue,) studied this question.