Resolution of hypertrophic osteopathy in a 2‐year‐old filly

This article reports the successful management of a 2‐year‐old Thoroughbred filly that presented with clinical signs of hypertrophic osteopathy, diffuse granulomatous dermatitis, lethargy and inappetence. An infectious primary focus was suspected due to an elevated white blood cell count (WBC), marked neutrophilia and dramatically increased serum amyloid A (SAA) and plasma fibrinogen levels. After failure to respond to a range of antimicrobial treatments, an actinomycetes bacterial infection, such as Mycobacterium avium or Rhodococcus equi, was suspected and the horse was started on rifampicin and clarithromycin treatment, which resulted in a rapid and pronounced improvement in clinical signs. After 10 weeks of treatment the skeletal manifestations had regressed, both clinically and radiographically, in addition to normalisation of the WBC count, SAA and fibrinogen levels.     

Haemoabdomen and colitis following a colon displacement in a 9‐year‐old Thoroughbred mare

This report describes acute haemoabdomen following phenylephrine administration in a case treated for left dorsal displacement of the large colon. The horse also subsequently developed a severe colitis which was treated with aggressive medical therapy.     

Caecal duplication in a 13‐year‐old Thoroughbred

A 13‐year‐old Thoroughbred gelding was presented for evaluation of recurrent colic of 4 weeks duration. These colic episodes were mild and responsive to medical therapy. Episodes of colic became more frequent and more painful. Exploratory laparotomy revealed a large intestine duplication with a cystic structure located at the caecocolic junction that was unable to be exteriorized and therefore not amenable to surgical correction. Thirty‐six hours following surgery, the horse became acutely painful, sweaty, and febrile suggesting gastrointestinal rupture. Post mortem examination showed a 0.6 × 1 m duplication and a 0.5 × 0.6 m cystic dilation that was probably associated with the caecum. There was a 10 × 30 cm area of rupture located within the duplication. Histological evaluation confirmed the presence of a true duplication.     

Haemolytic anaemia as a complication following colic surgery in a 10‐year‐old Arabian stallion

Immune‐mediated haemolytic anaemia is rare in the horse. This case report discusses the clinical presentation and treatment of this condition in an Arabian stallion following abdominal surgery for large colon volvulus. On Day 10 of hospitalisation the stallion's PCV dropped by 10% whilst his total solids remained stable, consistent with haemolytic anaemia. The stallion was treated with whole blood transfusions and dexamethasone and recovered to be discharged on Day 42. This is an interesting example of immune mediated haemolytic anaemia associated with a complicated gastrointestinal condition. It demonstrates the wide variety of potential aetiologies underlying a haemolytic episode and the necessity for expedient treatment.     

Ataxia and weakness as uncommon primary manifestations of hepatic encephalopathy in a 15‐year‐old trotter gelding

A 15‐year‐old trotter gelding was evaluated because of an acute onset of ataxia in all 4 limbs. There was no known history of trauma. The gelding showed grade 2/5 ataxia in all 4 limbs, which was localised after clinical neurological examination to the cervical vertebral spinal cord. Initial therapy consisted of oral anti‐inflammatory doses of prednisolone and antimicrobial treatment with potentiated sulphonamides. The ataxia progressed to grade 3/5 at Day 10 of hospitalisation. Additionally, the horse was slightly depressed and showed spontaneous yawning during examination. Facial sensation was blunted. Blood chemistry revealed a marked elevation of liver specific enzymes and blood ammonia levels. Transcutaneous abdominal ultrasonography revealed hepatomegaly. Due to a guarded prognosis, the horse was subjected to euthanasia. At necropsy the left lateral liver lobe was markedly enlarged and showed a firm texture, whereas the cranial part and the right and quadratic liver lobe displayed a severe and diffuse atrophy. Histopathologically, the left lateral liver lobe revealed a moderate to severe cirrhosis with a severe, diffuse hepatocellular iron‐accumulation. Increased numbers of Alzheimer type II astrocytes in the cerebral cortex and cerebral white matter vacuolisation were indicative for encephalopathy. These findings were interpreted as haemosiderosis and cirrhosis of the liver with consecutive hepatic encephalopathy. Aetiologically, haemosiderosis should be considered as a cause of liver cirrhosis with consecutive hepatic encephalopathy. Although hepatic encephalopathy in horses usually presents with predominating cerebral signs, it has to be taken into account as a differential diagnosis in cases of acute onset generalised ataxia.     

Cerebellar abiotrophy in a 6‐year‐old Arabian mare

Cerebellar abiotrophy (CA) is an uncommon neurological disease that most commonly affects Arabian horses. Affected horses are typically identified within the first 6 months of life. Intention tremor, wide based stance and ataxia are common clinical signs observed in affected individuals. No treatment is available for resolution of clinical signs. Definitive diagnosis is based on histopathological examination of cerebellar tissue, which is characterised by loss of Purkinje cell layer. This report describes a case of cerebellar abiotrophy that had a delayed diagnosis until 6 years of age.     

CASE REPORT: Anomalous nasolacrimal openings in a 2‐year‐old Morgan filly

This case report describes the clinical, diagnostic, computed tomography findings, and surgical treatment of a 2‐year‐old Morgan filly with bilateral, proximal, and distal anomalous nasolacrimal duct openings.     

4‐Methylpyrazole as a treatment in naturally occurring ethylene glycol intoxication in cats

Objective – To describe the clinical experience and therapeutic use of fomepizole (4‐methylpyrazole [4‐MP]) in 3 cats with naturally occurring ethylene glycol (EG) toxicity. Case or Series Summary – All cats were documented to be EG positive by an ethylene glycol test kit. This report describes the dose of 4‐MP used, available clinicopathological data, and clinical progression during hospitalization. All patients survived to discharge. New or Unique Information Provided – IV use of 4‐MP at 125 mg/kg as an initial dose and 31.25 mg/kg at 12, 24, and 36 hours is safe and effective for treatment of naturally occurring EG toxicity in cats. Increased HCO₃ concentrations were noted after IV use of 4‐MP. This is the first report documenting the successful treatment of naturally occurring EG intoxication in cats with 4‐MP.     

Lawsonia intracellularis proliferative enteropathy in a 3.5‐year‐old miniature horse

A 3.5‐year‐old miniature horse gelding was evaluated for signs of colic and decreased faecal production. Initial clinical pathology showed severe hypoproteinaemia with an albumin concentration <10 g/l. Abdominal ultrasound identified multiple loops of small intestine with significantly increased wall thickness. Diagnosis of equine proliferative enteropathy was based on clinical and laboratory findings, as well as a positive faecal polymerase chain reaction and positive antibody titre (>1:240) to Lawsonia intracellularis. Treatment with intravenous oxytetracylcine and additional supportive care gradually resolved the clinical and laboratory abnormalities.     

Caecal lipomatosis as a cause of colic in a 9‐year‐old gelding

Lipomatosis is an uncommon cause of colic. This case report details the pre‐ and intraoperative findings of a 9‐year‐old gelding, presented with acute abdominal pain. Exploratory laparotomy revealed a massive fatty infiltrate involving an extensive portion of the base and mid‐body of the caecum. To the authors' knowledge, this is the first report of an infiltrative lipomatous lesion of the equine caecum.     

Mandibular squamous cell carcinoma in a 5‐year‐old Tennessee Walking Horse

Squamous cell carcinoma (SCC) is the second most common neoplasm reported in the horse, but occurs rarely in the oral cavity. Clinical signs may be insidious in onset and mimic other non‐neoplastic processes, thus delaying appropriate treatment. Timely evaluation and advanced diagnostic imaging may offer the opportunity to initiate definitive treatment. This report describes a young gelding with mandibular SCC that was evaluated for mandibular swelling failing to respond to symptomatic therapy.     

B‐cell intestinal lymphoma with Mott cell differentiation in a 1‐year‐old miniature Dachshund

Abstract: A 1‐year‐old intact female miniature Dachshund was presented with hematochezia, vomiting, and diarrhea of more than 1‐week duration. An abdominal mass was palpated, which at exploratory surgery was found to be a 7‐cm‐long thickened section of ileum. The thickened ileum was resected. Impression smears revealed numerous small‐ to medium‐sized lymphocytes, with a smaller number of cells resembling Mott cells. The Mott‐like cells contained multiple pale vacuoles that were positive for periodic acid‐Schiff (PAS) in wet‐fixed smears, consistent with Russell bodies. Histologic evaluation of the surgically excised ileum revealed 2 populations of neoplastic lymphoid cells. The majority were uniform medium‐sized lymphocytes with hyperchromatic oval or round nuclei and inconspicuous nucleoli. The remaining cells resembled Mott cells, which contained several PAS‐positive eosinophilic globules in the cytoplasm, occasionally compressing the nucleus. The majority of neoplastic cells stained positively for vimentin, CD20, CD79a, and Pax‐5, but were negative for CD3 and lysozyme; 43.5% of cells stained positively for Ki‐67. The Mott cells were strongly positive for immunoglobulin but were negative for Pax‐5. Using electron microscopy, a homogenous substance of intermediate electron density was observed frequently in the cisternae of rough endoplasmic reticulum in the cytoplasm of the Mott cells, and rarely in the perinuclear cisternae of the lymphoid cells, corresponding to the site of immunoglobulin staining. Monoclonal rearrangement of immunoglobulin heavy‐chain (IgH) gene was observed by PCR testing for lymphocyte–antigen receptor rearrangement. The morphologic features, immunophenotype, and IgH gene rearrangement verified the lymphoid cells were neoplastic (mature cell type) and had a B‐cell phenotype, with evidence of immunoglobulin production and differentiation into Mott cells. This case was unusual because of the age of the dog and because most intestinal lymphomas are T‐cell phenotype. The Mott cell morphology also differed from typical mature B‐cell lymphoma types and may be a unique B‐cell lymphoma variant.     

Cutaneous habronemiasis in a 9‐year‐old Arab gelding in the United Kingdom

Cutaneous habronemiasis causes ulcerative granulating lesions in the skin of equids. Dramatic exuberant tissue may be seen, which becomes traumatised by the horse. To the authors' knowledge, cutaneous habronemiasis has not previously been documented on the distal limb of horses in the UK. Cutaneous habronemiasis should be considered as a potential differential diagnosis for ulcerative granulating skin lesions on the distal limb of the horse.     

Large pituitary adenoma in an 8‐year‐old Arabian stallion

An 8‐year‐old Arabian stallion weighing 361 kg presented to Louisiana State University Veterinary Teaching Hospital with a 3‐month history of weight loss, exercise intolerance, long hair coat and recent history of seizures and aimless wandering in the pasture. An initial presumptive diagnosis of pituitary pars intermedia dysfunction (PPID) was made based on clinical signs. The initial examination revealed weight loss and loss of body condition (BCS 3/9), hypertrichosis, muscle wasting and reluctance to move when prompted. A neurological examination revealed dull mentation with no evidence of proprioceptive deficits in the limbs. Mild hyperglycaemia and a stress leucogram were noted on initial biochemical panel and haematology, respectively. Plasma adrenocorticotrophic hormone (ACTH) concentrations before and after thyrotropin releasing hormone (TRH) stimulation were markedly increased. Rapid slice computed tomography (CT) scan of the head before and after contrast revealed a large mass in the region of the pituitary gland suggestive of macroadenoma causing PPID. Prior to imaging, treatment consisted of supportive nursing care. Due to size of the pituitary gland (measuring 4.6 × 4.6 × 3.8 cm) and the presence of seizure‐like activity and dull mentation, the stallion was subjected to euthanasia. A necropsy was not performed. Pituitary macroadenomas in horses affected with PPID, who show neurological signs such as seizure‐like activity, dull mentation and aimless wandering, might have a poor prognosis and treatment with pergolide mesylate might not reduce pituitary gland size or relieve clinical signs. A CT scan is indicated in horses with neurological signs suspected of PPID to further evaluate pituitary gland size and surrounding structures and rule out other causes to better assess prognosis.     

Atypical histopathological findings in a 15‐year‐old Warmblood gelding diagnosed with anhidrosis in a temperate climate

This case report describes the atypical histopathological findings in a horse with anhidrosis that presented for evaluation of suspected respiratory disease during autumn/winter in a temperate climate. Anhidrosis in this horse was associated with mononuclear infiltration of T lymphocytes around sweat glands, a finding not previously reported in cases of equine anhidrosis. This report highlights the importance of considering anhidrosis as a differential diagnosis in the investigation of respiratory disease and illustrates that the condition can occur in horses residing in temperate climates.     

Carcinoma of an accessory genital gland in a 23‐year‐old Camargue gelding

This report describes the case management, histopathological and post mortem findings in a 23‐year‐old gelding with a peri‐rectal mass. The mass was debulked surgically and submitted samples revealed it to be a poorly differentiated carcinoma. In the post operative period the horse developed signs of abdominal pain and dysuria and was subjected to euthanasia. Post mortem examination revealed a large infiltrative mass located between the rectum and urethra, consistent with a carcinoma of an accessory genital gland, most likely the seminal vesicle.     

Intra‐thoracic gossypiboma (textiloma) in a 6‐year‐old cocker spaniel

This report documents the first case of gossypiboma (textiloma) identified within the thorax of a dog. CT findings, surgical removal and histopathology are described. Intra‐thoracic gossypiboma has not previously been reported in dogs and is rarely reported in the human medical literature, where it is most commonly associated with previous cardiac or pulmonary surgery. This dog had previously had a thoracotomy for attempted surgical correction of a persistent right aortic arch and left ligamentum arteriosum 6 years prior to presentation. A brief review of the previous literature and recommendations for prevention of this condition are provided.     

Surgical treatment of a rostral mandibular complex odontoma in a 3‐year‐old horse

Complex odontomas are rare odontogenic tumours in horses comprised of a combination of mesenchymal and epithelial tissues. Examination, radiographic and histopathological findings in this patient all represent the typical behaviour of a complex odontoma. Oral tumours in horses may have treatment limitations due to tumour size and location. Similar to treatment in other species, surgical enucleation was curative for this type of tumour.