We present a case of a 76-year-old Caucasian woman with combined primary hypoparathyroidism and vitamin D deficiency resulting in life-threatening hypocalcaemia.
She has a history of COPD and initially presented in 2002 with an exacerbation of her airways disease. During treatment for her condition an incidental note was made of hypocalcaemia (calcium 1.62 mmol/l). PTH was minimally elevated at the time but 25-hydroxycholecalciferol was low (4.2 ng/ml). She was commenced on calcium and vitamin D therapy.
She was readmitted in 2005 with a further exacerbation of her COPD. The calcium and vitamin D was not on her current prescription. During her admission she was noted to have intermittent weakness of her limbs with twitching. During these episodes she became drowsy and her oxygen saturations fell. They were initially described as seizures. CT of her brain was normal.
Upon subsequent re-evaluation of these episodes, the possibility of tetany was raised and the previous history of hypocalcaemia was discovered. Calcium level was 0.98 mmol/l (corrected 1.27 mmol/l). She had normal renal function and magnesium level. PTH was inappropriately low at 2.0 pmol/l.
She was commenced on calcium, vitamin D and alfacalcidol with subsequent increase in her calcium levels and resolution of her symptoms.
Primary hypoparathyroidism is a rare endocrinopathy. The combination with vitamin D deficiency is rarer still. This demonstrates how rare conditions can co-exist and how re-evaluation is necessary if the aetiology and the clinical picture is inconsistent.