Differential Diagnosis for 80 yo Female with Hypercalcemia and AKI
- Single most likely diagnosis
- Multiple Myeloma: The patient's hypercalcemia, acute kidney injury (AKI), elevated free kappa light chains, and an abnormal kappa/lambda ratio are highly suggestive of multiple myeloma. The presence of a high IgA level on SPEP further supports this diagnosis, as IgA multiple myeloma can present with these laboratory findings.
- Other Likely diagnoses
- Monoclonal Gammopathy of Undetermined Significance (MGUS): Although less likely given the severity of symptoms, MGUS could be considered if the patient's condition is not as advanced. However, the significant elevation in free kappa light chains and the abnormal kappa/lambda ratio lean more towards a more aggressive process like multiple myeloma.
- Waldenström's Macroglobulinemia: This condition, characterized by an IgM monoclonal protein, could potentially cause hypercalcemia and AKI, but the IgM level is not markedly elevated in this case, making it less likely.
- Do Not Miss diagnoses
- Hypercalcemia of Malignancy (from other cancers): It's crucial to rule out other malignancies that could cause hypercalcemia, such as breast cancer, lung cancer, or lymphoma, as these conditions require different management strategies.
- Primary Hyperparathyroidism: Although less likely given the context of elevated light chains, primary hyperparathyroidism can cause hypercalcemia and AKI. Missing this diagnosis could lead to inappropriate management.
- Rare diagnoses
- Light Chain Amyloidosis: This condition involves the deposition of light chain fragments in various tissues and could potentially cause AKI and hypercalcemia, although it is less common and would typically present with other systemic symptoms.
- Heavy Chain Disease: A rare form of B-cell lymphoproliferative disorder that could present with similar laboratory findings, but it is much less common than multiple myeloma.