Differential Diagnosis

The patient's presentation of bone pain, bone edema on MRI, and a history of elevated calcium levels, along with hypertension and thyroid disease, suggests a multifactorial etiology. Here's a categorized differential diagnosis:

• Single most likely diagnosis

  • Primary Hyperparathyroidism: Although the TSH is normal, the one-time finding of elevated calcium in the context of bone pain and edema could suggest primary hyperparathyroidism, especially if the thyroid disease is not directly related to the bone symptoms. This condition can lead to hypercalcemia, which in turn can cause bone resorption and pain.

• Other Likely diagnoses

  • Paget's Disease of Bone: Characterized by localized rapid bone turnover, leading to bone pain and edema. The MRI findings of bone edema at multiple sites could be consistent with this diagnosis.
  • Osteonecrosis: Given the patient's history of hypertension and possibly steroid use for other conditions (though not mentioned), osteonecrosis could be a consideration, especially if the bone edema is localized to specific areas like the lower legs.
  • Bone Metastases: Although less likely without a known primary malignancy, bone metastases could present with bone pain and edema. The absence of systemic symptoms or a known cancer does not rule out this possibility entirely.

• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)

  • Multiple Myeloma: A plasma cell dyscrasia that can present with bone pain, hypercalcemia, and anemia. Although rheumatoid labs were normal, myeloma should be considered due to its potential severity and the need for early intervention.
  • Lymphoma with Bone Involvement: Similar to myeloma, lymphoma can cause bone pain and edema, along with systemic symptoms. Early diagnosis is crucial for effective treatment.

• Rare diagnoses

  • Osteopetrosis: A rare genetic disorder characterized by increased bone density due to impaired osteoclast function, leading to bone pain and potentially elevated calcium levels due to immobilization hypercalcemia.
  • Fibrous Dysplasia: A condition where normal bone is replaced with fibrous tissue, leading to weakened bones, pain, and potentially elevated bone turnover markers.

Each of these diagnoses requires further investigation, including specific lab tests (e.g., parathyroid hormone levels for primary hyperparathyroidism, serum protein electrophoresis for myeloma), imaging studies, and potentially bone biopsies to confirm the diagnosis and guide treatment.