Endocrine Abstracts

JOINT750

Background: Coeliac disease (CD) is an autoimmune disorder triggered by gluten in genetically predisposed individuals causing intestinal inflammation and villous atrophy leading to malabsorption of essential nutrients. While hypocalcaemia is a known complication due to impaired absorption of calcium and vitamin D, it is rarely the presenting symptom of undiagnosed coeliac disease. This case highlights the diagnostic challenge when mild hypocalcaemia leads to the discovery of an underlying gastrointestinal disorder.

Case Presentation: A 63-year-old male presented with a history of fatigue, intermittent paraesthesia, and muscle cramps. He denied any symptoms of overt tetany. Laboratory investigations revealed low serum calcium (2.12), borderline low 25-hydroxyvitamin D level (35), normal phosphate, magnesium, and raised PTH suggesting secondary hyperparathyroidism. Renal and liver function test results were normal. A 24-hour calcium-to-creatinine ratio was less than 0.01. He was commenced on Vitamin D replacement. After being adequately replaced with Vitamin D, he however remained persistently hypocalcaemic. PTH or even partial Vitamin D resistance was initially suspected as potential causes. The patient was started on a trial of Calcium carbonate. However, the patient’s symptoms persisted, prompting further investigations. The patient underwent a screening test for coeliac disease at a primary care centre, which revealed elevated Anti-transglutaminase (anti-tTG) antibody levels. Notably, the patient had no gastrointestinal symptoms, such as diarrhoea or weight loss, which are commonly associated with coeliac disease. The patient declined endoscopy and biopsy and hence could not ascertain the tissue diagnosis of coeliac disease. However, strong positive anti-tTG antibody levels and a family history of coeliac disease were sufficient to confirm the diagnosis clinically.

Management and OutcomeThe patient was started on a strict gluten-free diet. Over several months, his serum calcium normalised, and his symptoms resolved. Emphasis was placed on nutritional counselling, including fortified foods and lifestyle modifications.

Conclusions: This case emphasises the importance of considering coeliac disease in patients presenting with unexplained hypocalcaemia, especially when accompanied by nonspecific symptoms such as fatigue and muscle cramps. Early recognition of coeliac disease can prevent the complications associated with nutrient malabsorption and lead to effective management. This case also underscores the need for comprehensive evaluation when mild hypocalcaemia is detected without clear dietary or metabolic causes and emphasis on further evaluation and investigation given persistent symptoms albeit in the setting of mild hypocalcemia should be made as was evident in this patient.