AAZV 2021

Signalment:Male pup northern elephant seal

History:Upon presentation, he had linear ventral skin fold ulcers, a mild leukocytosis and moderate lymphocytosis, and elevated GGT and alkaline phosphatase. The ventral fold dermatitis progressed despite antibiotic treatment, and cytology revealed numerous mostly rod-shaped bacteria, granulocytes, and small to large lymphocytes. Acute phase protein measurements and protein gel electrophoresis were suggestive of a polyclonal gammopathy most consistent with an inflammatory process. The marked leukocytosis and lymphocytosis continued with sudden thrombocytopenia, increased BUN, and elevation in other liver biomarkers. Blood smears revealed several lymphocytes with “flower-like” nuclear morphology, as well as large lymphocytes with increased nucleus: cytoplasm ratios with fewer small to intermediate lymphocytes, segmented and band neutrophils, and erythroid precursors. While in care, the animal’s mentation and hydration had initially improved however ultimately declined in the last week of care. Euthanasia was elected based on the clinical condition as well as the cytologic, hematologic, and serum biochemical results.

Gross Lesions:All lymph nodes were markedly enlarged, firm, bulging and homogenous on cut surface. The tonsils, spleen and thymus were also markedly enlarged and firm. The jejunum, ileum, and most notably the colon had dark red, thickened, corrugated mucosa with distinct white firm nodules. There were also multiple linear ulcerations of the ventral abdominal skin folds with granulation tissue and minimal fibrinosuppurative exudate, as well as a thickened multinodular and congested urinary bladder mucosa.