The Hidden Dangers of Hypercalcemia: A Case Report of Undiagnosed Symptoms Leading to Complications.

Hypercalcemia is a relatively common metabolic abnormality; however, it is frequently undiagnosed. It often manifests with neuropsychiatric, gastrointestinal, renal, and musculoskeletal symptoms. We report the case of a 75-year-old woman with a history of syncope, anorexia, asthenia, weight loss, polydipsia, polyuria, visual hallucinations, confusion, generalized tonic-clonic seizures, and depression. Laboratory workup revealed severe hypercalcemia (ionized calcium: 1.81 mmol/L) with normal renal function and significantly elevated parathyroid hormone (PTH) levels. A diagnosis of primary hyperparathyroidism was made, and the patient was treated with fluid therapy and zoledronic acid, resulting in the resolution of the symptoms.