Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: August 25, 2025 • View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Differential Diagnosis for Elevated PTH, Normal Calcium, and GFR 90

Single Most Likely Diagnosis

  • Primary Hyperparathyroidism with mild or early disease: This condition often presents with elevated parathyroid hormone (PTH) levels and normal or slightly elevated calcium levels. The normal GFR suggests that the kidneys are functioning well, which is consistent with primary hyperparathyroidism.

Other Likely Diagnoses

  • Vitamin D deficiency: Low vitamin D levels can cause an increase in PTH as the body attempts to maintain calcium homeostasis. Normal calcium levels in this context could be due to the body's compensatory mechanisms.
  • Magnesium deficiency: Magnesium plays a role in PTH regulation, and its deficiency can lead to increased PTH secretion. Normal calcium and GFR 90 could be seen in this scenario.
  • Familial hypocalciuric hypercalcemia (FHH): Although calcium levels are normal in this case, FHH can sometimes present with normal calcium due to the body's efficient calcium reabsorption mechanisms. The elevated PTH could be a clue to this diagnosis.

Do Not Miss Diagnoses

  • Lithium-induced hyperparathyroidism: Lithium therapy can cause an increase in PTH secretion, leading to hyperparathyroidism. It's crucial to inquire about medication history, as missing this diagnosis could lead to unnecessary surgery or inappropriate management.
  • Parathyroid gland adenoma or hyperplasia in the context of multiple endocrine neoplasia (MEN) syndromes: These conditions can present with elevated PTH and normal calcium, especially in early stages. Missing these diagnoses could have significant implications for the patient and their family due to the potential for other associated endocrine tumors.

Rare Diagnoses

  • Parathyroid hormone-related protein (PTHrP) secreting tumors: Although rare, certain tumors can secrete PTHrP, leading to elevated PTH-like activity. Normal calcium levels might be seen if the tumor's secretory activity is mild or intermittent.
  • Genetic disorders affecting the calcium-sensing receptor (CaSR): Mutations in the CaSR gene can lead to altered PTH secretion and calcium homeostasis. These conditions are rare but should be considered in the differential diagnosis, especially if other family members are affected.

Related Questions

What's the next step in managing a patient with elevated Thyroid Peroxidase (TPO) Antibody, slightly low Free T4, and elevated Thyroglobulin levels?
What are the treatment options for sympathetically maintained pain versus other neuropathic pain conditions?
What is the recommended treatment for infections caused by KPC (Klebsiella pneumoniae carbapenemase)-producing bacteria?
What is the step-by-step procedure for a fracture of the proximal tibia treated with plating via posterior and anterior approaches?
What is the recommended empirical antibiotic therapy for a patient with gram-negative bacilli in endotracheal secretions?
What are the strategies to reduce ketosis in a patient with small bowel obstruction and hyperketonemia?

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.

Ask Question