Neurotropic T-cell-rich B-cell lymphoma in a 14-year-old Morgan gelding

A 14-year-old Morgan gelding was presented for progressive weakness and muscle atrophy. The horse was initially diagnosed with equine protozoal myelitis based on history, physical examination, and laboratory diagnostics. Despite therapy, the horse declined clinically and was euthanized. Necropsy revealed a rare form of neurotropic lymphoma, described in this report.     

Extensive and invasive guttural pouch granuloma in a 2-year-old gelding

This report describes a case of an unusually extensive and invasive fungal granuloma within the right guttural pouch and its surrounding area of a 2-year-old Noriker gelding, causing diverse neurogenic deficits and tissue destruction. The gelding was initially presented with cachexia, unilateral nasal discharge, intermittent fever, swelling of the right side of the head, facial nerve paralysis and dysphagia. The right guttural pouch was not accessible to endoscopic examination initially, but after anti-inflammatory medical management, empyema and an extensive, solid mass appeared within the guttural pouch. Surgical exploration and excision were attempted but were unsuccessful. Histopathological examination identified Aspergillus fumigatus as the causative infective agent of the extensive fungal granuloma, and the consequent invasion and destruction of surrounding bone and soft tissue structures.     

Nephrogenic diabetes insipidus in a 14-year-old gelding

Abstract

CASE HISTORY: A 14-year-old Cleveland Bay cross gelding was presented with severe urinary incontinence that had been present for 1 year, and chronic polydipsia and polyuria over 4 years. Water intake had been recorded as 240 L over a 24-hour period.

CLINICAL FINDINGS: The horse had marked urinary incontinence and polyuria and polydipsia. The urine was markedly hyposthenuric, but no abnormalities on urinalysis were detected. There were no other abnormal clinical or neurological signs. Haematological and serum biochemical examinations showed no abnormalities and ultrasonographic and endoscopic examination of the urinary tract did not reveal any abnormalities. The horse underwent a modified water deprivation test and failed to concentrate its urine after 5 days. 1-desamino-8-d-arginine vasopressin (DDAVP) was administered I/V but the urine remained isosthenuric with a specific gravity of 1.010.

DIAGNOSIS: Nephrogenic diabetes insipidus. A definitive cause of the urinary incontinence was not found but overflow incontinence was considered a possibility.

CLINICAL RELEVENCE: Despite being a rare condition in the horse diabetes insipidus should be considered in cases of severe polydipsia and polyuria in mature horses.     

Sebaceous adenitis in a 7-year-old Arabian gelding

A 7-year-old Arabian gelding was presented with a 9-month history of progressive patches of nonpruritic scaling, crusting, alopecia, and leukoderma of the periocular areas and muzzle, becoming generalized over time. Sebaceous adenitis was diagnosed on histopathologic examination. Lesions resolved without treatment, coinciding with regression of a sarcoid on the neck.     

Lumbar fractures in a 5-year-old Warmblood cross gelding

This case report describes multiple lumbar vertebral fractures in a 5-year-old Warmblood cross gelding used for low-level exercise, with no known history of trauma. Clinical signs included intermittent severe pain, distress and unwillingness to move. When the horse was in less severe pain, he tilted the pelvis to one side when walking and also when trotting. Fracture of the 6th lumbar vertebral body was diagnosed by transrectal ultrasonography and confirmed by post-mortem computed tomography. Post-mortem examination also revealed a complete fracture of the 3rd lumbar vertebral body. Previously, lumbar fractures have only been reported in racing breeds and ante mortem diagnosis has been limited to scintigraphy.     

Halicephalobus gingivalis infection in a 5-year-old Tinker gelding

A 5-year old Tinker gelding was referred to the Department of Equine Sciences with a left eye uveitis and fever. At presentation the horse showed a mild lethargy, fever and decreased vision of the left eye. Rectal examination revealed an enlarged left kidney, with a hard and an irregular surface. The cranial mesentery artery had an enlarged and irregular aspect. Blood analysis showed anaemia, leucocytosis, increased blood urea nitrogen and creatinine and a hyperproteinemia. Urine analysis repeatedly showed a marked proteinuria and an increased gammaGT/creatinine ratio. The amount of abdominal fluid was slightly increased. However, the aspect, amount of cells and protein were normal. In the following two days the fever persisted and the horse showed anorexia and severe neurological signs. The horse was euthanized with permission of the owner. Post mortem examination showed a generalized parasitic infestation of Halicephalobus gingivalis in the uvea of the left eye, the kidneys and the central nerve system.     

Ossifying fibroma as a cause of blindness in a 5-year-old Quarter Horse gelding

A 5-year-old Quarter Horse gelding presented to Texas A&M University Veterinary Medical Teaching Hospital with a several week history of bilateral blindness. Neurological deficits included an absent menace response and severe atrophy of the optic nerve head in the left eye (OS) as well as decreased vision in the right eye (OD). Advanced imaging consisting of computed tomography (CT) and magnetic resonance imaging (MRI) confirmed a large mass in the base of the skull invading the sinuses and asymmetrically compressing the optic nerves rostral to the optic chiasm. Due to the size and location of the mass as well as severity of associated neurological signs, humane euthanasia was elected. Necropsy examination identified a large mass effacing the sphenopalatine sinuses and compressing the optic nerves. Histologically, the mass was identified as an ossifying fibroma (OF) and degeneration of the optic nerves was confirmed. As an OF in this location has never been described in a horse, this case demonstrates a new differential for blindness in horses.     

Ballistic shock wave lithotripsy in an 18-year-old thoroughbred gelding

Prolonged postoperative recuperation time and restricted exercise were circumvented by using ballistic shock wave lithotripsy to break up an 8-cm diameter vesical calculus and by flushing out the sand-like residue under epidural anesthesia with the horse standing. Recovery was uneventful.     

Aryepiglottic lymphoma in a 19-year-old Paint gelding treated with excision and adjunctive radiotherapy

This case report describes the diagnosis and treatment of an aryepiglottic tumour in a 19-year-old Paint gelding. Diagnostic work-up included physical examination, endoscopic evaluation of the upper airway, and histopathology of the mass following removal. Treatment consisted of surgical excision of the aryepiglottic mass under endoscopic guidance followed by a 100 Gy dose of radiation delivered with strontium-90 plesiotherapy to the surgical bed at 72 h post-operatively. The radiation applicator was passed through the left nostril and the application area was confirmed via endoscopic evaluation. Histopathology, including immunohistochemistry, confirmed that the aryepiglottic tumour was T cell lymphoma. Recheck examination, including physical examination and upper airway endoscopy, was performed 1, 3 and 6 months following treatment and local recurrence was not observed. Local control with minimal morbidity can be achieved with surgical excision of equine lymphoma followed by strontium-90 plesiotherapy.     

Small intestinal adenomatous polyps resulting in chronic obstruction in a 3-year-old Quarter Horse gelding

A 3-year-old, Quarter Horse gelding was admitted to Kansas State University Veterinary Health Center with a primary complaint of colic. The horse had a 3-month history of recurrent colic and progressive weight loss. On physical examination, the horse was quiet, alert and responsive. The horse's mucous membranes were pink and capillary refill time was 2 s. His rectal temperature was 37.6°C (99.6°F), heart rate was 56 beats/min and respiration rate was 16 breaths/min. Rectal palpation revealed an approximately 5 cm dilated, firm, tubular, mass traversing from left caudal abdomen to mid abdomen. Nasogastric intubation obtained 6 L net reflux. A 5 cm diameter small intestinal intraluminal mass was detected by abdominal ultrasound. Complete blood count, serum chemistry and peritoneal fluid analysis were performed and all results were unremarkable. The horse was humanely euthanised due to pain and financial constraints. Post-mortem examination and histopathology revealed a 15 × 5 × 5 cm polyp with multiple smaller satellite polyps that obstructed the distal duodenum. Colic was considered secondary to small intestinal obstruction and luminal distension caused by the adenomatous polyps. To the authors’ knowledge, this is the first report to include ultrasound images of a small intestine adenomatous polyp that caused small intestinal obstruction and colic in a 3-year-old horse.     

Obstructive urolithiasis, unilateral hydronephrosis, and probable nephrolithiasis in a 12-year-old Clydesdale gelding

A 12-year-old Clydesdale gelding was presented for colic and dysuria. Obstructive urolithiasis and chronic renal disease were diagnosed via transurethral endoscopy and percutaneous ultrasonography. Nephroliths, hydronephrosis, and peri-ureteral fibrosis were present. Surgical intervention was declined and the gelding was managed medically with antibiotics and dietary modification.