Differential Diagnosis for 11-year-old Female with Anxiety and Hypercalcemia
Single Most Likely Diagnosis
- Familial Hypocalciuric Hypercalcemia (FHH): This condition is characterized by hypercalcemia due to an inherited abnormality in the calcium-sensing receptor. It often presents with mild hypercalcemia, as seen in this patient, and can be associated with anxiety due to the hypercalcemia's effects on the nervous system. The normal creatinine and absence of other electrolyte imbalances support this diagnosis.
Other Likely Diagnoses
- Primary Hyperparathyroidism: Although less common in children, primary hyperparathyroidism can cause hypercalcemia. The normal TSH and T4 levels help to rule out thyroid-related causes, but parathyroid hormone (PTH) levels would need to be checked to confirm or rule out this diagnosis.
- Vitamin D Intoxication: Excessive intake of vitamin D can lead to hypercalcemia. This could be a consideration if the patient has been taking supplements or has been exposed to excessive amounts of vitamin D.
- Idiopathic Hypercalcemia of Infancy: Though the patient is 11, some cases of idiopathic hypercalcemia can persist into childhood. This diagnosis would require further investigation into the patient's history and possibly genetic testing.
Do Not Miss Diagnoses
- Malignancy (e.g., Leukemia, Lymphoma): Although the CBC is normal with only a slight elevation in absolute lymphocytes, malignancy can sometimes present with hypercalcemia due to various mechanisms, including paraneoplastic syndromes. It's crucial to consider and rule out malignancy due to its severe implications.
- Sarcoidosis: This condition can cause hypercalcemia due to increased vitamin D production by macrophages in granulomas. While less common in children, it's a diagnosis that should not be missed due to its potential for serious complications.
- Hyperthyroidism (TSH and T4 may be normal in early stages or with certain assays): Although the TSH and T4 are normal, it's essential to ensure that hyperthyroidism is thoroughly ruled out, possibly with additional thyroid function tests or consideration of free T4 and T3 levels.
Rare Diagnoses
- Williams Syndrome: A genetic disorder that can include hypercalcemia among its features. It's characterized by distinctive facial features, intellectual disability, and a friendly demeanor.
- Jansen's Metaphyseal Chondrodysplasia: A rare genetic disorder causing hypercalcemia and skeletal abnormalities.
- Other Genetic Disorders: Such as those affecting the PTH or vitamin D pathways, which could lead to hypercalcemia. Genetic testing might be necessary to diagnose these conditions.