Natural killer-like T-cell lymphoma in a calf

Immunophenotype investigation in feline intestinal non-B-cell lymphoma

Lymphoma is the most common tumour of domestic cats, developing most frequently in the small intestine. Feline small intestinal lymphoma predominantly demonstrates a T-cell immunophenotype identified by standard immunopositivity for T cells with CD3 or immunopositivity for B cells with CD20. In contrast, a wide spectrum of immunohistochemical antibodies are applied in humans to diagnose the various specific lymphoma subtypes according to the WHO classification. Our aim was to augment our knowledge of immunophenotypes in feline non-B-cell lymphomas forming macroscopic masses in the intestinal tract. We evaluated the combined immunohistochemistry and flow cytometry findings from 15 cases. Neoplastic lymphoid cells were immunopositive for CD3 in 93% (14/15), granzyme B in 87% (13/15), CD5 in 20% (3/15), CD8 in 13% (2/15), CD4 in 7% (1/15) and CD56 in 7% (1/15) of cases. Cytotoxic granules indicating a cytotoxic origin of the neoplastic cells were identified by histopathology only in 13% (2/15) and by cytology in 47% (7/15) of the cases. Without immunohistochemical labelling of the cytotoxic protein granzyme B, the cytotoxic status would have been missed in 46% (6/13) of the cytological and in 85% (11/13) of the histopathological slides. These findings suggest that more complex immunophenotyping may advance our understanding and help prognosticate small intestinal T-cell lymphoma in cats.

Precursor B-1 B Cell Lymphoma in a Newborn Calf

A newborn Holstein female calf had neoplastic lesions in the skin and within the thoracic and abdominal cavities but not in the bone marrow, spleen, thymus, or most lymph nodes. Because the tumor cells were positive for CD79a (B cell marker), CD5 (B-1 cell marker) and terminal deoxynucleotidyl transferase (marker for immature lymphoid precursors), a diagnosis of precursor B-1 B cell lymphoma was made. The diagnosis was strongly supported by the fact that B-1 cells can develop in the fetus, unlike B-2 cells, which are produced after birth. The lymphoma was distinct from the typical calf form of lymphoma of B-2 cell origin, which does not express CD5 and is characterized by generalized lymphadenopathy and involvement of the bone marrow, blood and spleen.

T-cell lymphoma in the nasal cavity of a Brown Swiss heifer

Background

Tumours of the upper respiratory tract are relatively common in cattle, but to our knowledge, there have been no reports of lymphoma of the nasal cavity. This case report describes the findings in a 22-month-old Brown Swiss heifer with T-cell lymphoma of the nasal cavity.

Case presentation

The main clinical findings were lacrimation and swelling of the head above and below the right eye, mild exophthalmos, third eyelid prolapse, purulent ocular discharge and congestion of scleral blood vessels. An endoscope could only be introduced a few centimetres into the right nasal cavity because of an obstructing mass in the nasal passage. Radiographs showed a mass in the right nasal cavity and maxillary sinus. A tentative diagnosis of neoplasia of the right nasal cavity was made and the heifer was euthanased and necropsied. A firm, tan mass measuring 10 by 13 by 15 cm in the right half of the head occupied the entire right nasal cavity. A final diagnosis of high-grade, malignant, small-sized T-cell lymphoma was made based on histological and immunohistochemical evaluation. A distinction between αβ T-cell or γδ T-cell lymphoma was not made.

Conclusions

This report on T-cell lymphoma in the nasal cavity of a cow suggests that nasal lymphoma should be included in the list of differential diagnosis of conditions associated with dyspnoea and stertorous breathing in cattle.

Ultrasonography of the spleen, liver, gallbladder, caudal vena cava and portal vein in healthy calves from birth to 104 days of age

Background

Many of the ultrasonographic abdominal findings of adult cattle probably also apply to calves. However, significant changes associated with ruminal growth and transition from a milk to a roughage diet occur in young calves during the first few months, and it can be expected that ultrasonographic features of organs adjacent to the rumen such as spleen and liver also undergo significant changes. These have not been investigated to date and therefore the goal of this study was to describe ultrasonographic findings of the spleen, liver, gallbladder, caudal vena cava and portal vein in six healthy calves from birth to 104 days of age. Standing calves were examined ultrasonographically six times at three-week intervals starting on the first or second day of life using a 5.0-MHz transducer and techniques described previously.

Results

The spleen was imaged on the left at the 5th to 12th intercostal spaces. The dorsal and ventral visible limits ran from cranioventral to caudodorsal because of superimposition of the lungs. The size of the spleen was largest at the 7th and 8th intercostal spaces and the maximum thickness was measured at the 9th to 12th intercostal spaces. The liver was seen in all calves on the right and could be imaged at the 5th to 12th intercostal spaces and the area caudal to the last rib. Similar to the spleen, the dorsal visible margin of the liver ran parallel to the ventral border of the lungs. The visible size of the liver was largest at the 8th to 11th intercostal spaces and the maximum thickness was measured at the 8th and 9th intercostal spaces. The parenchymal pattern consisted of numerous fine echoes homogeneously distributed over the entire organ. The gallbladder was most commonly seen at the 9th intercostal space and was circular, oval or pear-shaped on ultrasonograms. It extended beyond the ventral border of the liver depending on the amount of bile. The caudal vena cava was triangular in cross section but sometimes had a round or oval profile and was always seen in at least one intercostal space. The maximum circumference was measured at the 10th and 11th intercostal spaces. The portal vein was circular or oval in cross section and was characterised by stellate ramifications branching into the liver parenchyma. The portal vein could always be imaged at the 7th to 11th intercostal spaces and its mean diameter at the 9th to 11th intercostal spaces ranged from 1.2 cm to 1.8 cm.

Conclusions

The ultrasonographic findings of the spleen, liver, gallbladder, caudal vena cava and portal vein in six healthy Holstein-Friesian calves from birth to 104 days of age serve as reference values for the examination of these anatomical structures in diseased calves.

Mast cell sarcoma with megakaryocytic differentiation in a calf

A case of mast cell sarcoma in a 5-month-old Holstein female calf is described. Macroscopically, enlargement of the spleen, lymph nodes, tonsils and kidneys was noted, and there were tumor masses in the neck region and on the pleura and peritoneum. The pericardium and uterine and ureter walls were also involved by tumor. Most neoplastic cells had eosinophilic granules, which were metachromatic and positive for naphthol AS-D chloroacetate esterase and tryptase, whereas smaller numbers of cells were positive for factor VIII-related antigen, a marker of megakaryocytes. Some of the predominant type of these tumor cells were found within the epithelia of the lungs, tonsils, gastrointestinal tract, liver, ureters, urinary bladder and uterus. Their normal counterparts were considered to be globule leukocytes.

Intranuclear coccidiosis in a calf

A case of intranuclear coccidiosis in an 11-month-old female Japanese Black calf is described. Because the calf exhibited diarrhea and failure to grow and then became moribund, euthanasia was performed. Histologically, the small intestinal villi were highly atrophic, and the epithelial cells frequently had meronts or merozoites within the nuclei. A few intranuclear gametocytes were also seen. The presence of Eimeria alabamensis-specific DNA in the lesions was demonstrated by polymerase chain reaction and nucleotide sequence analyses. Electron microscopy disclosed that most parasites were within nuclear inclusions encircled by the two membranes derived from the nuclear envelope, and that intracytoplasmic meronts and merozoites were in direct contact with the cytosol. Apparently, mature merozoites could be free without destruction of the host cells, and this may be associated with the relatively low pathogenicity of this coccidium.