Cognitive decline reversed by cinacalcet

Abstract

An 85-year-old lady with decreased mood and low energy was found to have an elevated serum corrected calcium concentration of 2.8 mmol/L (reference range: 2.1–2.6 mmol/L). Plasma parathyroid hormone concentration was elevated at 390 pg/mL (reference range: 10–85 pg/mL). She had a past history of renal calculi. Renal function, full blood picture, erythrocyte sedimentation rate, 24-h urinary calcium excretion, serum immunoglobulins, chest X-ray and serum angiotensin converting enzyme concentrations were all normal. Myeloma screening was negative. Serum-corrected calcium concentrations fell following rehydration. A thiazide diuretic was discontinued. A sestamibi scan (Figure 1) was unhelpful in pre-operative localization. The patient declined parathyroidectomy. Figure 1. Sestamibi parathyroid subtraction scan showing heterogenous uptake with greater uptake in the left lobe than the right. One year later, she was admitted with dehydration with serum-corrected calcium concentration elevated at 2.93 mmol/L. This did not reduce in response to rehydration or diuretic therapy and had a minimal reduction with intravenous bisphosphonates. Mini Mental State Examination (MMSE)1 score was 21/30 and serum-corrected …