A Novel Adult Case of Recurrent Acute Pancreatitis Caused by Hypercalcemia With Concurrent Manifestation of Posterior Reversible Encephalopathy Syndrome Revealing Undiagnosed Primary Hyperparathyroidism due to an Underlying Parathyroid Adenoma.

BACKGROUND: Hypercalcemia-induced posterior reversible encephalopathy syndrome (PRES) is a rare entity primarily associated with iatrogenic vitamin D/calcium overdose, malignancy, or, infrequently, primary hyperparathyroidism.

CASE REPORT: We present a novel case of an adult male from rural India who experienced recurrent acute pancreatitis caused by hypercalcemia with concurrent manifestation of PRES. Diagnostic evaluation revealed markedly elevated serum calcium levels and parathyroid hormone concentrations, consistent with primary hyperparathyroidism. Imaging studies identified a parathyroid adenoma near the right thyroid lobe, subsequently surgically excised.

DISCUSSION: This case underscores the importance of considering primary hyperparathyroidism as an underlying cause of PRES, especially in the absence of acute arterial hypertension or autonomic dysfunction. Early recognition and intervention are essential in mitigating the morbidity and mortality of PRES.