HYPERFERRITINEMIA ASSOCIATED WITH MALIGNANT HISTIOCYTOSIS IN A DOG

A 3.5-year-old male Golden Retriever with lethargy, generalized lympha denopathy, and hepatosplenomegaly was determined to have malignant his tiocytosis, based on the morphologic appearance of neoplastic cells by light and electron microscopic examination, evidence of erythrophagoc ytosis, the presence of diffuse nonspecific esterase activity, and imm unohistochemical demonstration of vimentin intermediate filaments. Bec ause of the appearance of abundant iron stores in the bone marrow, ser um was obtained for determination of iron, total iron binding capacity , and ferritin values. Serum ferritin concentrations were markedly inc reased. Measurement of serum ferritin concentrations may be useful in supporting a diagnosis of malignant histiocytosis, and the monitoring of serum ferritin concentrations may be useful for assessing treatment regression of the disease.