T-cell lymphoma-associated hemophagocytic syndrome in an American Pit Bull Terrier

Abstract

A 3-y-old, intact female, American Pit Bull Terrier was presented because of acute onset of anorexia and a large subcutaneous submandibular mass that had been present for 3 wk. The submandibular mass, 2 engorged black-legged ticks on the dorsum of the neck, pyrexia, and icterus were seen on physical examination. Abnormal laboratory test results included a positive Anaplasma antibody test, severe thrombocytopenia, mild nonregenerative anemia, hyperbilirubinemia, and elevated liver enzyme activities. Cytology of the mass was interpreted as marked septic purulent inflammation with acute hemorrhage. Treatment with doxycycline for anaplasmosis was unsuccessful, and the patient died at an emergency follow-up visit 2 d after the initial presentation. Autopsy and histopathology revealed widespread metastasis of a presumptive histiocytic neoplasm with associated hemophagocytosis seen in lymph nodes (LNs), liver, and spleen. Immunohistochemistry yielded a definitive diagnosis of a CD3+/CD18+ T-cell lymphoma. In this case of canine lymphoma-associated hemophagocytic syndrome, hemophagocytes were observed as >2% of neoplastic cells in the liver, spleen, and LN histologically, a scarce or unreported finding, to our knowledge. The prognosis was grave, with a short survival time after the onset of clinical signs.

An Evaluation of Hemostatic Dysregulation in Canine Multicentric Lymphoma

“…These cytokines contribute to the development of multiple cytopenias, including thrombocytopenia [63]. Hypofibrinogenemia, commonly observed in our cases, is a well-established feature of human LHAS [64]. Acquired HPS can be associated with neoplasia, and lymphoma is the most common neoplasm associated with this condition [65].…”

“…Acquired HPS can be associated with neoplasia, and lymphoma is the most common neoplasm associated with this condition [65]. Recent reports have documented episodes of LAHS and thrombocytopenia in a small number of dogs [63,64]. Notably, the vast majority of cases, both in human and canine populations, are associated with T-cell lymphoma.…”