Heterobilharzia americana infection as a cause of hepatic parasitic granulomas in a horse

CASE DESCRIPTION-A 22-year-old American Paint Horse gelding from the Gulf Coast region of Texas was evaluated for regrowth of a perirectal squamous cell carcinoma that had been surgically removed 11 months previously. CLINICAL FINDINGS-A necrotic and ulcerated mass was present below the anus. The horse had paraphimosis and was having difficulty with urination. Histologic examination of the mass revealed that it was squamous cell carcinoma, and the horse was euthanized because of the unlikelihood that the mass could be adequately resected and its close proximity to the urethra. OUTCOME-At necropsy, in addition to the squamous cell carcinoma, hundreds of round, white to pale yellow nodules were disseminated throughout the liver, resulting in a so-called starry-sky appearance. Similar granulomas were seen in the right caudal lung lobe and small intestinal serosa. A single granuloma in the liver, which differed from the others by its larger size, contained a pair of adult schistosomes. Several hepatic granuloma specimens were used for PCR amplification and sequencing. Use of primers specific for a portion of the Heterobilharzia americana small subunit rRNA gene resulted in amplification of a 487-base pair product that had 100% sequence identity with H americana. CLINICAL RELEVANCE-Severe cases of disseminated granulomas in the liver of horses may result in a liver with a grossly abnormal starry-sky pattern. To our knowledge, this is the first report documenting the association of granulomas with H americana infection along with adult schistosomes in the liver of a horse.     

用于营养物质代谢的动静脉插管技术Ⅰ.插管及血流量计安装手术

为了研究营养物质在动物内脏组织的代谢规律,需要测定门静脉的血流速度和取得血液样品.对消化道器官(或称门静脉回流内脏,PDV)来说,主要生理功能是吸收营养,同时本身也要进行各种营养物质的代谢.因此测定门静脉血流速度非常重要.目前测定门静脉血流速度的方式有两种.其一是直接测定,比如安装流量计,另一种是通过示踪剂稀释法间接测定.     

Intramuscular hemangiosarcoma with pulmonary metastasis in a horse

Intramuscular hemangiosarcoma resulting in severe anemia and thrombocytopenia was diagnosed in a 3-year-old Thoroughbred filly. Necropsy revealed multiple tumors within skeletal muscles and multiple pulmonary metastases.     

Malignant mast cell neoplasia with local metastasis in a horse

A 12-year-old Arab stallion was presented with a chronically swollen right carpus resulting in profound lameness of the same leg. An incisional biopsy of subcutaneous tissue from the right carpus submitted for cytology and histopathology revealed large numbers of eosinophils interspersed by substantial numbers of variably sized and granulated mast cells. Fungal culture of a subcutaneous tissue sample taken from the right carpus was negative. Serial full blood counts revealed persistent mature eosinophilia, not accompanied by a mastocytaemia, neutrophilia without left shift and persistent hyperfibrinogenaemia. After humane destruction, dissection of the affected limb revealed a thick layer of connective tissue deposited around the right carpal joint. Within the connective tissue were embedded many small 0.25-1 cm diameter yellow gritty nodules, which consisted of dystrophic calcification and necrotic cell debris. The tendons enveloped by the connective tissue mass had limited function. The right axillary lymph node was moderately enlarged, yellow-brown and moist. Histopathological examination revealed a moderately well differentiated mast cell neoplasm with evidence of metastasis to the regional lymph node. In horses, malignant mast cell neoplasia is rare, while metastasis has only been reported in one other horse. Eosinophilia associated with equine mast cell neoplasia has not been reported previously but is recorded in mast cell neoplasia in the dog.     

Gross anatomy of the portal vein and hepatic artery ramifications in dogs: corrosion cast study

The anatomical variations of the portal vein and the hepatic artery ramifications were analysed on liver corrosion casts in 20 dogs as a possible aid in the surgical management of the organ. The portal vein ramified similarly in all dogs. It divided into the smaller right portal branch from which vessels for the caudate process and both right lobes arose and the substantial left portal branch, which supplied the remaining liver portions and in 12 cases also the dorsal part of the right lateral lobe. Right lateral, right medial and left branches are the major arteries originating from the hepatic artery; however, their origin and course varied among individual animals. In 10 livers, the right lateral and the left branches originated from the hepatic artery, while the right medial branch arose from the left branch and usually supplied the right medial lobe solely. In nine livers, the right medial branch arose directly from the hepatic artery and supplied quadrate lobe and gallbladder as well, while in one liver the common artery, which subsequently divided into lobar branches, branched away from the hepatic artery. An additional branch for the caudate process, originating directly from the hepatic artery, was observed in 10 livers. Certain liver portions received the arterial blood from two major branches, which was particularly characteristic for the right medial lobe (six livers) and caudate process (10 livers). The course of the major arterial branches was also variable, although they proceeded in close anatomical relationship with the portal vein branches. The left arterial branch accompanied the left portal branch on its dorsal aspect (15 cases) or crossed it from the caudal aspect (five cases). The right lateral branch crossed the initial parts of the left and right portal branches either from cranial (12 cases) or caudal aspects (eight cases), while the right medial branch always crossed the left portal branch from its caudal aspect.     

Clinical course of renal adenocarcinoma associated with hypercupraemia in a horse

A four-year-old shire mare with haematuria, colic, terminal weight loss and an abdominal mass had a large unilateral renal adenocarcinoma. Clinical signs were monitored for 11 months. Increased serum copper concentrations were measured on two occasions. Hypercupraemia is discussed as a possible paraneoplastic change.     

Ocular manifestations of a metastatic adenocarcinoma in a horse

A 10‐year‐old German Warmblood gelding was referred to the Equine Department of the Vetsuisse Faculty, University of Zurich, Switzerland, for an iris mass OD, lethargy, intermittent fever, and coughing. Ophthalmic examination revealed a 7 × 9 mm raised, fleshy, whitish to pinkish, vascularized iris mass at the 2 o`clock position OD. Fundic examination showed multifocal round, brown to black, slightly raised lesions with indistinct margins and a surrounding hyperreflective zone OU. Physical examination revealed a temperature of 39.2 °C, sinus tachycardia, preputial and ventral edema, and an enlarged right mandibular lymph node. Results of a complete blood count and plasma biochemical profile showed mild anemia, leukocytosis, and thrombocytopenia. Severe splenopathy, moderate splenomegaly, and severe pulmonary pathology with nodules and large areas of consolidated lung parenchyma were observed on abdominal ultrasound and thoracic radiographs, respectively. Fine needle aspirates of the enlarged mandibular lymph node showed malignant epithelial neoplastic cells. The horse was euthanized because of the poor prognosis and subsequently underwent postmortem examination. Macroscopic necropsy and histopathology revealed an adenocarcinoma of suspected pulmonary origin with involvement of eyes, heart, liver, kidneys, spleen, diaphragm, skeletal muscles, mandibular, pulmonary, and internal iliac lymph nodes. Metastatic adenocarcinoma should be considered as a differential diagnosis in horses with iris masses, multifocal chorioretinal infiltrates, and clinical signs that conform to a paraneoplastic syndrome.     

Severe involvement of cerebral neopallidum in a dog with hepatic encephalopathy

This report describes a unique distribution of cerebral cortical necrotic lesion, which was diagnosed as hepatic encephalopathy in a 2-year-old Maltese dog. The dog showed splenocaval shunt and small liver with marked hepatocellular fatty degeneration. Histopathologic examination revealed that diffuse laminar cortical necrosis composed of neuronal necrosis, marked infiltration of gitter macrophages, and astrogliosis were found bilaterally in the dorsolateral area of the cerebrum. No necrotic lesions were observed in the cerebral paleopallium and archipallium, the central gray matter, cerebellum, and brain stem. Astrocytes with large and pale nuclei (Alzheimer type II astrocytes) were apparent throughout the brain. Immunohistochemically, a decrease of immunostains for glutamine synthetase and glutamate transporter antibodies was seen in Alzheimer type II astrocytes and neuropil. This is, to our knowledge, the first report of extensive involvement of cerebral neopallidum in canine hepatic encephalopathy.     

Ileal diverticulum as a cause of chronic colic in a horse

A 4-year-old Thoroughbred gelding with a history of chronic colic was referred for evaluation of signs of abdominal pain. Exploratory laparotomy revealed a diverticulum of the distal portion of the ileum located between the layers of the mesentery. The diverticulum was similar in location and appearance to acquired ileal diverticula described in human beings. Complete bypass of the diverticulum by ileocecostomy resulted in apparent resolution of the chronic colic in this horse.     

Gastric impaction and obstruction of the small intestine associated with persimmon phytobezoar in a horse

Signs of mild colic, intermittent lethargy, and weight loss of 6 weeks' duration in a 2-year-old Quarter Horse gelding were attributed to persimmon (Diospyros virginiana) phytobezoar formation. Diagnosis of the phytobezoar was facilitated by gastric endoscopy. Signs of gastrointestinal tract obstruction were associated with a large phytobezoar in the lumen of the stomach, gastric ulceration, and obstruction of the small intestine (as a consequence of fragmentation of the primary bezoar). Conservative treatment, using mineral oil and dioctyl sodium sulfosuccinate, was unsuccessful. A celiotomy was performed, and gastric impaction and partial obstruction of the small intestine associated with phytobezoar formation and fragmentation were identified. The horse made a complete recovery following removal of all phytobezoars. Persimmon phytobezoar should be considered in the fall and winter as a possible cause of lethargy, colic, and weight loss in horses allowed access to persimmon fruit.     

Squamous cell carcinoma as a cause of dyspnea and blindness in a horse

An 8-year-old Quarter Horse mare was examined for chronic nasal discharge and obstruction of both nasal passages. A solid mass lesion was identified in the maxillary sinuses, soft palate, nasal and pharyngeal cavities. Palliative surgery was used to debulk the lesion and facilitate nasal airflow. Squamous cell carcinoma was diagnosed from surgical biopsies. Approximately 7-8 weeks after surgery, the mare was observed to be acutely blind. Ophthalmologic examination revealed central origin blindness and active retinitis. The squamous cell carcinoma had reobstructed the nasal passages. Pressure by the expanding tumor deformed the ethmoid and sphenoid bones resulting in compression of the optic tracts. No bony invasion by the tumor was present.     

Severe polyuria and polydipsia as major clinical signs in a horse with unilateral renal adenocarcinoma

A 14‐year‐old Swiss Warmblood gelding was presented with chronic severe polyuria, polydipsia and weight loss. At the time of admission, water intake was 240 l/day. On rectal examination, a large mass was identified in the left dorsal abdominal quadrant, which was shown to originate from the left kidney by transabdominal ultrasonographic examination. Unilateral nephrectomy via flank incision was performed under general anaesthesia. Histopathological examination of the tumour revealed a papillary renal adenocarcinoma. Successful outcome and survival was documented 13 months after surgery. Severe polyuria and polydipsia should be considered as major clinical signs for renal carcinoma in horses, which can be successfully treated with unilateral nephrectomy if no signs of metastatic spread are evident.     

Portal streamlining as a cause of nonuniform hepatic distribution of sodium pertechnetate during per-rectal portal scintigraphy in the dog

The purpose of this study was to evaluate nonuniform patterns of vascular distribution of pertechnetate in the dog during per-rectal portal scintigraphy. Ninety-two studies were reviewed retrospectively to document the patterns of radionuclide distribution. Forty-five studies were classified as normal and 47 were classified as diagnostic for a macrovascular portosystemic shunt. In these dogs, shunt fractions were calculated and compared using a t-test. In dogs with sufficient liver radioactivity for evaluation, the study was classified as having uniform, dorsal, central, or ventral radiopharmaceutical distributions. There were 51 animals (45 normal and six dogs with low-magnitude portosystemic shunts) with sufficient liver activity to assess the radionuclide distribution within the liver. A one-way ANOVA was used to compare shunt fractions between each of the distribution patterns. Two dogs were anesthetized and selective portovenograms were performed. Portovenograms were compared with the scintigraphic images to correlate the vascular distribution of the right, central, and left divisional branches of the portal vein. The shunt fraction in the 45 normal dogs was significantly lower than in the dogs with portosystemic shunts (5.7% +/- 4.8% vs. 78.6% +/- 20.0% (mean +/- SD), P < 0.001). Of the 51 dogs with sufficient liver activity to classify the pattern of distribution, there were 15/51 (31.4%) with uniform radionuclide distribution, 10/51 (19.6%) with focal dorsal distribution, 15/51 (29.4%) with focal ventral distribution, and 10/51 (19.6%) with focal central distribution. There was no significant difference in the shunt fractions between the groups. There were six dogs diagnosed with low-magnitude portosystemic shunt with sufficient liver radioactivity to categorize the vascular distribution of the radionuclide within the liver. Of these six dogs, two had focal dorsal distribution, one had focal central, one had focal ventral and two had uniform distribution. Focal dorsal distribution could result from streamlining of the radionuclide into the right divisional branch of the portal vein. Focal ventral distribution could result from streamlining the radionuclide into the left divisional branch of the portal vein. Focal central distribution could result from streamlining the radionuclide into the central divisional branch of the portal vein.     

Antemortem diagnosis of hepatic adenocarcinoma in a ewe

A 4-year-old ewe with weight loss, anorexia, and high liver enzyme activities was diagnosed at necropsy as having cholangiocellular carcinoma that had metastasized to kidneys, adrenal glands, heart, lungs, mediastinum, and peritoneal surface of the diaphragm. Cholangiocellular carcinoma is an uncommon neoplasm of sheep. Evaluation of liver tissue obtained via ultrasound-guided percutaneous liver biopsy had suggested an antemortem diagnosis of adenocarcinoma of the liver.