HYPERCALCEMIA ASSOCIATED WITH LYMPHOMAS IN THE FERRET (MUSTELA PUTORIUS FURO): FOUR CASES

An elevated level of serum calcium (hypercalcemia) is an uncommon finding in the domestic ferret (Mustela putorius furo). In dogs and cats, one of the more common causes of parathyroid-independent hypercalcemia is humoral hypercalcemia of malignancy (HHM), a paraneoplastic syndrome associated with certain tumors. HHM has been sparely reported in the ferret. The authors have identified 4 patients with cytologically or histopathologically confirmed lymphomas and hypercalcemia characterized by persistent serum total calcium levels >= 12.1 mg/dL, serum ionized calcium >= 1.60 mmol/L, and suppressed intact parathyroid hormone levels. These findings suggest a diagnosis of HHM. The most common clinical signs were anorexia, lethargy, and hindlimb weakness. Parathyroid hormone-related protein levels were quantified in 3 cases and showed elevations consistent with HHM. Immunohistochemistry was performed on 2 of the lymphomas, which labeled negative for all stains used. Copyright 2018 Elsevier Inc. All rights reserved.