Symptoms of Parathyroid Adenoma
Parathyroid adenomas often present with symptoms related to hypercalcemia, including bone demineralization, fractures, nephrolithiasis, nephrocalcinosis, muscle weakness, and neurocognitive disorders. 1
Common Clinical Presentations
Asymptomatic Presentation
- In countries with routine biochemical screening (US, Canada, Europe), parathyroid adenomas are frequently discovered incidentally as asymptomatic hypercalcemia 1
- Despite lack of symptoms, treatment is typically indicated due to potential negative effects of long-term hypercalcemia 1, 2
Symptomatic Presentation
Symptoms are categorized by organ system involvement:
Skeletal Manifestations
- Bone pain and tenderness
- Pathologic fractures
- Osteoporosis or osteopenia
- Bone demineralization 1
Renal Manifestations
- Nephrolithiasis (kidney stones)
- Nephrocalcinosis
- Polyuria
- Recurrent urinary tract infections
- Progressive renal dysfunction 1, 2
Neuromuscular and Neuropsychiatric Manifestations
- Muscle weakness and fatigue
- Neurocognitive disorders
- Depression
- Memory impairment
- Confusion
- Lethargy 1, 2
Gastrointestinal Manifestations
Cardiovascular Manifestations
- Hypertension
- Shortened QT interval on ECG
- Arrhythmias 3
Severe Presentations
Parathyroid Crisis
- Rare but life-threatening complication of primary hyperparathyroidism
- Characterized by markedly elevated calcium levels (>3.5 mmol/L)
- Presents with severe symptoms including:
- Requires immediate medical intervention to prevent mortality 5
Laboratory Findings
- Elevated serum calcium or ionized calcium
- Elevated or inappropriately normal parathyroid hormone (PTH) levels
- Low or low-normal phosphorus levels
- Elevated 24-hour urinary calcium (in most cases)
- Reduced 25-OH vitamin D levels (often) 2
Diagnostic Pitfalls
- Symptoms of parathyroid adenoma can be vague and nonspecific, leading to misdiagnosis or delayed diagnosis 3
- Patients may present with seemingly unrelated complaints like hypertensive crisis, abdominal pain, or psychiatric symptoms 3, 6
- Parathyroid adenomas can occasionally be intrathyroidal or ectopic, making clinical diagnosis more challenging 7, 6
- Multigland disease should be considered in patients with risk factors such as MEN syndromes, lithium therapy, or previous radiotherapy 2, 7
When to Suspect Parathyroid Adenoma
- Unexplained hypercalcemia, especially with elevated or inappropriately normal PTH
- Recurrent kidney stones
- Unexplained osteoporosis, especially in men or premenopausal women
- Fragility fractures
- Vague constitutional symptoms (fatigue, weakness, depression) with laboratory evidence of hypercalcemia 2
Early recognition of these symptoms is crucial for timely diagnosis and treatment, as surgical excision of the abnormally functioning parathyroid tissue is the definitive cure for primary hyperparathyroidism caused by parathyroid adenoma 1, 2.