Knee brown tumor revealing a primary hyperparathyroidism: a case report

Area of Science:

• Endocrinology
• Oncology
• Skeletal Biology

Background:

• Primary hyperparathyroidism is a frequent endocrine condition, often asymptomatic and incidentally discovered via hypercalcemia.
• Brown tumors are rare but serious skeletal complications associated with hyperparathyroidism.

Observation:

• This paper details an unusual case of primary hyperparathyroidism.
• The condition presented as a brown tumor in a 28-year-old female with a knee mass.
• Initial diagnosis was prompted by a bone tumor presentation.

Findings:

• Blood tests confirmed hypercalcemia and hyperparathyroidism.
• A bone biopsy of the knee lesion revealed giant cell granulomas, characteristic of brown tumors.
• The underlying cause was identified as a parathyroid adenoma.

Implications:

• This case underscores the importance of considering rare skeletal manifestations in primary hyperparathyroidism.
• Early diagnosis and management of parathyroid adenomas are crucial to prevent severe bone complications like brown tumors.
• Highlights the diagnostic challenge when brown tumors present as primary bone lesions.