Diffuse Skeletal [۱۸F]FDG Uptake from Renal Osteodystrophy with Parathyroid Hyperplasia in an ESRD Patient: A Case Report

Introduction: Secondary and tertiary hyperparathyroidism (HPT) are common complications in patients with end-stage renal disease (ESRD) and may result in renal osteodystrophy. While [۱۸F]-FDG PET/CT is primarily used to evaluate malignancy, it may occasionally reveal metabolic or endocrine abnormalities.Case presentation: A ۴۵-year-old male with ESRD on hemodialysis presented with generalized bone pain and radiologic suspicion of malignancy. [۱۸F]-FDG PET/CT demonstrated diffusely increased skeletal uptake and multifocal lytic bone lesions, consistent with metabolic bone disease secondary to renal osteodystrophy. Incidental findings of soft tissue nodules in both tracheoesophageal grooves suggested parathyroid pathology. Subsequent [۹۹mTc]Tc-sestamibi SPECT/CT confirmed parathyroid adenomas/ hyperplasia. Laboratory tests revealed elevated calcium (۱۰.۸ mg/dL), phosphorus (۷.۲ mg/dL) and markedly increased parathyroid hormone (۳۱۲۰ pg/mL) levels.Discussion: This case highlights that diffuse skeletal [۱۸F]-FDG uptake in ESRD may mimic malignancy but actually represent metabolic bone disease due to secondary or tertiary HPT. The [۱۸F]-FDG PET/CT findings of parathyroid lesions were incidental, while [۹۹mTc]Tc-sestamibi SPECT/CT accurately localized the hyperfunctioning glands. Conclusion: FDG PET/CT can incidentally demonstrate metabolic bone disease and parathyroid-[۱۸F] abnormalities in ESRD, but [۹۹mTc]Tc-sestamibi SPECT/CT remains the preferred modality for parathyroid localization. Awareness of this potential finding may prevent misinterpretation and guide appropriate management.

کلیدواژه ها:

ESRD ، [۱۸F]-FDG PET/CT ، renal osteodystrophy ، hyperparathyroidism