Acute myeloblastic leukemia with associated BCR-ABL translocation in a dog

An 8-year-old male neutered Labrador Retriever was referred to the University of Wisconsin Veterinary Medical Teaching Hospital with a presumptive diagnosis of leukemia. Hematologic abnormalities included normal neutrophil count with a left shift, monocytosis, eosinophilia, thrombocytopenia, and circulating immature mononuclear cells. Bone marrow was effaced by immature hematopoietic cells of various morphologic appearances. In addition, large multinucleated cells were observed frequently. Flow cytometric analysis of nucleated cells in blood revealed 34% CD34(+) cells, consistent with acute leukemia. By immunocytochemical analysis of cells in blood and bone marrow, some mononuclear cells expressed CD18, myeloperoxidase, and CD11b, indicating myeloid origin; some, but not all, large multinucleated cells expressed CD117 and CD42b, the latter supporting megakaryocytic lineage. The diagnosis was acute myeloblastic leukemia without maturation (AML-M1). To identify genetic aberrations associated with this malignancy, cells from formalin-fixed paraffin-embedded bone marrow were analyzed cytogenetically by multicolor fluorescence in situ hybridization (FISH). Co-localization of bacterial artificial chromosome (BAC) containing BCR and ABL was evident in 32% of cells. This confirmed the presence of the canine BCR-ABL translocation or Raleigh chromosome. In people, the analogous translocation or Philadelphia chromosome is characteristic of chronic myelogenous leukemia (CML) and is rarely reported in AML. BCR-ABL translocation also has been identified in dogs with CML; however, to our knowledge this is the first report of AML with a BCR-ABL translocation in a domestic animal.     

Two cases of reciprocal chromosomal translocation (4; 7)(p+; q-) (2; 8)(q-; q+) in piglets produced by ICSI

In this study, the karyotypes of 14 piglets from four different litters produced by intracytoplasmic sperm injection (ICSI) and embryo transfer were analysed. The chromosome analysis was based on a classical cytogenetic examination following the standard protocols of lymphocyte cultures. Two cases of reciprocal translocation [(4; 7)(p+; q-) and (2; 8)(q-; q+)] were detected in two female transgenic piglets. These animals showed neither anatomical nor physiological alterations and had normal growth. To our knowledge, this is the first karyotype study of piglets produced by ICSI.     

Xylazine-induced attenuation of dorsal displacement of the soft palate associated with epiglottic dysfunction in a horse

An 18-month-old Quarter Horse filly was evaluated because of dorsal displacement of the soft palate associated with epiglottic dysfunction that caused exercise intolerance and an abnormal respiratory noise. The abnormality of the epiglottis was corrected by use of a sedative dose of xylazine hydrochloride. There was no familial predisposition to hyperkalemic periodic paralysis, which may cause similar laryngopharyngeal signs, and the horse did not respond to administration of acetazolamide. There was no known history of trauma that could have caused neuritis, which has also been suggested as a cause of laryngeal dysfunction. It was unusual that a complete response was obtained with xylazine hydrochloride, an alpha2-adrenergic agonist, although this drug has various effects on the respiratory tract in horses. It was also unusual that the response outlasted the sedative effect of the drug.     

Vestibular syndrome associated with an ependymoma in a cat

An ependymoma was diagnosed in a 4.5-year-old spayed Siamese cat with clinical signs of vestibular disease. Diagnosis was based on history, results of neurologic examination, and the finding of neoplastic cells in CSF. Necropsy revealed an ependymoma arising from the fourth ventricle of the ventricular CNS and involving the left medullary and cerebellar areas.     

Refractory seizures associated with an organic aciduria in a dog

A 6-month-old, female Cavalier King Charles spaniel exhibited seizures that were difficult to control with standard anticonvulsants over a 12-month period. The diagnosis of an organic aciduria with excessive excretion of hexanoylglycine was determined when the dog was 20 months old. Recurrent and cluster seizures were eventually controlled with the addition of levetiracetam to potassium bromide and phenobarbital.     

Budd-Chiari-like syndrome associated with an adrenal phaeochromocytoma in a dog

A nine-year-old dog was presented with sudden-onset ascites and a history of two previous syncopal episodes. Diagnostic tests pointed to a Budd-Chiari-like syndrome, with obstruction of the caudal vena cava between the liver and heart. The ascites was refractory to treatment and the dog was euthanased. On postmortem examination, a phaeochromocytoma of the left adrenal gland was present, with contiguous invasions into the caudal vena cava, extending cranially as far as the cavoatrial junction. To the authors' knowledge, this is the first reported case of a Budd-Chiari-like syndrome associated with a phaeochromocytoma in a dog.     

Cyclic estrous-like behavior in a spayed cat associated with excessive sex-hormone production by an adrenocortical carcinoma

A 15-year-old, spayed female domestic shorthair cat was evaluated for 1-year duration of cyclic intermittent estrous behavior. Diagnostic testing performed before referral, including baseline progesterone concentration, human chorionic gonadotropin (hCG) hormone stimulation test and surgical exploratory laparotomy, had remained inconclusive for a remnant ovary. Evaluation of sex hormones before and after adrenocorticotropic hormone (ACTH) administration revealed increased basal concentrations of androstenedione, estradiol, progesterone, and 17α-hydroxyprogesterone and normal ACTH-stimulated hormone concentrations. Enlargement of the right adrenal gland was identified by abdominal ultrasound. The cat underwent an adrenalectomy and histopathology of the excised adrenal gland was consistent with an adrenocortical carcinoma. Clinical signs resolved immediately following surgery, and most hormone concentrations declined to within or below the reference interval (RI) by 2 months after surgery.     

Marked hyperphosphatasemia associated with an acute leukemia in a Great Dane

This is the report of a 5‐year‐old male neutered Great Dane with an extreme leukocytosis (544.9 × 10⁹ cells/L; RI 5.2–13.9 × 10⁹ cells/L) characterized by highly atypical round cells. Cellular morphologic features such as cytoplasmic membrane blebs, a high nuclear‐to‐cytoplasmic ratio, and nuclear indentations and irregularities and large nucleoli, as well as immunocytochemistry for CD3 and CD79, myeloperoxidase cytochemistry, and clonality testing were not conclusive for myeloid or lymphoid origin. Marked alkaline hyperphosphatasemia was present at the first visit (2783.0 U/L; RI 6–80.0 U/L), followed by a 5‐fold increase (14,000 U/L) a week later, identified as being mostly contributed by the bone‐ALP isoform (11,062 U/L; RI 0–30 U/L). In addition, the atypical leukocytes were strongly positive for cytoplasmic ALP activity. In vitro lysis of a heparin blood sample resulted in a 1.7‐fold increase of ALP activity, supporting the origin of the hyperphosphatasemia at least in part from the leukemic cell population. To the authors’ knowledge, this is a unique case of alkaline hyperphosphatasemia, due at least to a leukemic cell population producing a bone‐ALP isoform, regardless of the exact nature of the leukemia.     

A nephrotic-like syndrome with an associated mesangio-proliferative glomerulopathy in a cow

A 3-year-old Limousin cow was admitted to the University of Georgia Teaching Hospital with a history of chronic weight loss and diarrhea of more than 1 year's duration. Clinical laboratory findings included proteinuria and hypoproteinemia and were suggestive of a nephrotic-like syndrome. Necropsy findings included generalized edema of the visceral organs and diffuse red glistening foci on the capsular and cut surfaces of the cortex of both kidneys. Microscopically, the kidney had hypercellular and hypersegmented glomeruli, focal glomerulosclerosis, periglomerular fibrosis, and tubular nephrosis. The glomerular hypercellularity was confirmed by electron microscopy to be due to increased mesangial cells.