Endocrine Abstracts

Introduction: Primary hyperparathyroidism (pHPT) is a common endocrine disorder usually diagnosed by the presence of elevated serum calcium levels with inappropriate normal or increased parathyroid hormone (PTH) serum levels. This condition has been reported in few cases of patients with sickle cell disease (SCD), a multisystem disorder with acute and chronic complications.

Observation: We report a case of a 63-year-old Tunisian woman with a history of homozygous sickle cell disease (SS phenotype), high blood pressure and atrial fibrillation, referred to the emergency department for hypercalcemia 3.68 mmol/l (n:2.25–2.6) with electrocardiogram (ECG) abnormalities. After hydration, a decrease of calcium level 2.82 mmol/l and normalized ECG, she was admitted to the endocrinology ward. Physical examination showed a centimetric basal cervical mass. Blood tests showed: hypophosphatemia 0.73 mmol/l (n: 0.78–1.52), an elevated parathyroid hormone level 1479 pg/ml (n: 26.5–96.5) and a moderate decrease in kidney function (creatinine clearance=44 ml/min). Urinary cast showed no hypercalciuria. This case was compatible with pHPT. Hypercalcemia was treated with oral route and intravenous hyper hydration along with bisphosphonate perfusions. Ultrasonography of the neck revealed a mass at the left inferior parathyroid lobe of 17×14 mm and the Sestamibi scan showed a 15 mm single left parathyroid adenoma. Renal echography revealed no nephrolithiasis albeit an aspect of chronic renal disease. Bone densitometry revealed osteoporosis (T scores of −3.5, −2.5 in lumbar spine and left hip respectively). Then the patient underwent an excision of the parathyroid adenoma. The histological analysis showed pseudo adenomatous parathyroid hyperplasia.

Discussion: Some explanations for the association of SCD with pHPT have been delineated in the literature, such as vitamin D deficiency, high levels of EPO du to chronic hemolysis which could stimulate the parathyroid glands and increased growth factors and fibroblastic growth factor which seem to promote parathyroid cells proliferation

Conclusion: If we consider pHPT to be a complication of SCD, calcium levels should be routinely checked, keeping in mind the fatality of hypercalcemia complication adding to that the threatening complications of SCD. Further research is required to underpin the association of SCD with pHPT.