Primary hyperparathyroidism presenting as anticonvulsant-induced osteomalacia.

Area of Science:

• Endocrinology
• Metabolic Bone Disease

Background:

• Anticonvulsant-induced osteomalacia is a known complication of certain medications.
• Primary hyperparathyroidism can present with non-specific symptoms, potentially leading to diagnostic challenges.

Observation:

• A patient exhibited classic signs of anticonvulsant-induced osteomalacia.
• Following vitamin D repletion and drug withdrawal, hypercalcemia and hyperparathyroidism persisted.

Findings:

• A parathyroid adenoma was surgically removed.
• Pre-existing hypercalcemia and nephrolithiasis indicated underlying primary hyperparathyroidism.
• Anticonvulsant therapy had obscured the diagnosis of primary hyperparathyroidism.

Implications:

• Highlights the importance of considering underlying endocrine disorders in patients with drug-induced metabolic bone disease.
• Emphasizes the need for thorough patient history to differentiate between drug effects and primary conditions.
• Underscores the potential for anticonvulsants to mask or mimic other endocrine pathologies.