Endocrine Abstracts

Introduction: The most frequent causes of hypercalcemia in the general population are primary hyperparathyroidism and malignancies. However, we must sometimes consider other causes, such as Cushing’s syndrome.

Clinical case: A 49-year-old man who was being assessed for hypertrophic cardiomyopathy was referred to our Endocrinology Clinic in order to investigate the incidental finding of hypercalcemia (11.08 mg/dl) with high PTH (84.6 pg/ml), hypophosphatemia (1.84 mg/dl) and low 25-hydroxy vitamin D (11.9 ng/ml). He was a former smoker with history of hypertension, type 2 diabetes mellitus, dyslipidaemia and sensorimotor axonal polyneuropathy. He was unable to stand upraight and walked with a cane because of limb weakness and intense lumbar pain. He had lost 10 kg in the previous month, and complained of asthenia and constipation with haematochezia. Examination revealed BMI 29.07 kg/m², BP 173/99 mmHg, aortic systolic murmur, skin bruising, neck hump and proximal limb muscle atrophy. Amyloidosis and multiple myeloma were ruled out. Bone densitometry and lumbar CT showed severe osteopenia and multiple vertebral fractures. Neck ultrasound showed a lesion suggestive of parathyroid adenoma, but the parathyroid scan showed no evidence of hyperparathyroidism. Fasting plasma cortisol was 38.6 μg/dl, and 51 μg/dl after 1 mg overnight dexamethasone suppression test. The 24 h urinary free cortisol level was 718 μg/dl. He was admitted in our Endocrinology Department for Cushing’s syndrome workup. The lab tests: ACTH 98.30 pg/ml, FSH 1.28 mUI/ml, LH 0.85 mUI/ml, free testosterone 0.76 mg/dl, FT4 0.62 ng/ml, TSH 0.58 ng/ml prolactine 12.1 ng/dl. A cranial MRI showed a pituitary tumor measuring 1.6×1.6×0.8 cm. The final diagnosis was Cushing’s disease and hypogonadism due to a pituitary adenoma. An abdominal scan was performed to evaluate haematochezia and weight loss, and a mass of 1.5×6 cm was found in the rectum along with multiple lesions in the liver suggestive of haemangioma but needing further confirmation.

Conclusion: In this clinical case hypercalcemia was the key symptom which guided us to the final diagnosis of Cushing’s disease. This is an unusual presentation, but the typical comorbidities (diabetes, central obesity, dyslipidaemia and hypertension) and complications (bone fractures) were present. With the presence of hyperparathyroidism, pituitary adenoma and a gastrointestinal mass, a MEN-1 syndrome must be considered. This case emphasizes the need for a comprehensive workup of the hypercalcemic patient.