Primary hyperparathyroidism (PHPT) is not uncommon. It has varied presentations ranging from asymptomatic disease to the classical stones, groans, and moans. The incidence and prevalence of frank diabetes mellitus (DM) is significantly increased in patients with hypercalcaemia. It may be difficult to differentiate symptoms of hypercalcaemia from DM. We present a case of improved glycaemia in a patient with DM following removal of parathyroid adenoma.
A 45-year-old female within a week of diagnosis with T2DM was referred to us for being symptomatic with extreme lethargy, polyuria, polydipsia, muscle aches and pains, iron deficiency anaemia, and dysphagia. She had coexisting uncontrolled hypertension, PCOS, obesity, osteoarthritis, depression past history of DVT, and bladder tumor removal. She was vitamin D deficient with a level <10 nmol/l. Biochemistry was suggestive of PHPT with raised corrected calcium of 3.04 mmol/l and an elevated PTH of 10.7 pmol/l. Glycaemic control was poor with a HbA1c of 74 mmol/mol. She had low haemoglobin of 11.4 gm% and a low MCV 75.7. Ultrasound of parathyroids showed a large 3.25×2.1 cm hypoechoic soft tissue mass inferior to lower pole of left lobe of thyroid suggestive of parathyroid adenoma. She refused to undergo upper GI endoscopy. Hypercalcaemia was managed with i.v. fluids and pamidronate infusion. Attempt was made to improve her glycaemic control on Metformin, Gliclazide, and Novomix 30 insulin. It was rather difficult to engage her with our services. 17 months into the diagnosis of PHPT, she finally agreed to have parathyroidectomy. Histology revealed a left lower lobe parathyroid adenoma. One and 6 months post-operatively, HbA1c improved to 58 and 51 mmol/mol. Her insulin needs dropped considerably.
This case highlights that primary hyperparathyroidism might contribute to hyperglycaemia in patients with DM. Parathyroidectomy may result in improvement in glycaemia and may reduce the need for use of anti-diabetic drugs or their dosage. Review of hypoglycaemic s is warranted post-parathyroidectomy.