Discordant calcium and parathyroid hormone with presumed epileptic seizures

Abstract

A 33-year-old woman presented for the first time at the age of 9 years with recurrent seizures and was subsequently treated for epilepsy for 2 years. At 11 years of age, it was noted that the patient had hypocalcemia with an increased parathyroid hormone (PTH) measured with use of an intact PTH assay. Serum calcium was 5.73 mg/dL [1.43 mmol/L; reference interval (RI) 8.82–10.42 mg/dL (2.2–2.6 mmol/L)]; serum phosphate was 10.42 mg/dL [3.36 mmol/L; RI 1.86–4.34 mg/dL (0.6 –1.4 mmol/L)]; and PTH was 319.68 pg/mL [33.9 pmol/L; RI 8.49–68.84 pg/mL (0.9 –7.3 mmol/ L)]. Vitamin D (Total 25-OH; 25-OH D2 and D3) concentrations, magnesium concentrations, liver and renal function tests were all normal. No other endocrine abnormalities such as thyroid or gonadotropin resistance were detected. The patient also was of short stature and was overweight. However, she became overweight after the age of 13 years (body mass index at 13 years was 22.8 kg/m2), and the short stature was not significant, as she was at the lower end of the RI for height at 1.55 m. There was no cognitive impairment. Positive Chvostek sign was observed but not Trousseau sign.