Metastatic Calcification in Allograft Kidney Due to Persistent Secondary Hyperparathyroidism: A Rare Cause of Graft Dysfunction.

Successful kidney transplant corrects mineral and bone disorderto a large extent; however, disorders can persistin up to 80% ofrecipients.We describe a case of persistent hyperparathyroidism with graft dysfunction and metastatic calcification in graft biopsy. A 48-yearold renal transplant recipient developed graft dysfunction 3 weeks after kidney transplant. During pretransplant workup, the recipient was found to have severe secondary hyperparathyroidism (intact parathyroid hormone level of 2000 pg/mL), which was managed and well controlled before transplant. Graft dysfunction was evaluated using algorithmic approach. Prerenal causes, tacrolimus toxicity, and infections were ruled out. Graft biopsy revealed several foci of tubular and parenchyma calcific deposits (microcalcinosis) with tubular injury. The patient was restarted on medical management of hyperparathyroidism, and he showed improvement over 6 weeks, along with creatinine level returning to nadir value. Vascular and graft calcification is an independent predictor of long-term graftfunction and overall mortality. This report describes the challenges that we faced in diagnosis and management of persistent hyperparathyroidism, as no randomized controlled trials and guidelines are available.