Concurrent atypical myoglobinuria and colon displacement in a filly

An 18‐month‐old pony filly was examined for acute colic and abdominal distension. The signs of colic failed to resolve following analgesic treatment. At exploratory laparotomy, a right dorsal displacement of the large colon was identified and corrected. On recovery from anaesthesia, the pony developed signs of widespread myopathy, confirmed by serum biochemistry evaluations. Myopathy consistent with atypical myoglobinuria was confirmed post mortem.     

The use of computed tomography in the diagnosis of an ectopic ureter in a Quarter Horse filly

This report describes a 4‐month‐old Quarter Horse filly with an ectopic ureter. The filly presented with signs of urinary incontinence, which had been present since birth. Computed tomography (CT) examination and cystoscopy confirmed a diagnosis of a unilateral ectopic ureter. A nephrectomy of the left kidney was performed and renal function was closely monitored post operatively. The filly was treated for abdominal chylous effusion as a post operative complication. The filly survived to discharge from the hospital, and maintained normal urinary function at 12 months post operatively.     

Primary malignant melanoma in the oesophagus of a foal

A 2‐month‐old filly was evaluated for severe colic. Ultrasound, abdominocentesis and physical examination findings prompted an abdominal exploratory surgery. Perforation of the stomach was discovered during the surgery. The filly was humanely subjected to euthanasia under anaesthesia and post mortem examination was performed. In addition to gastric and duodenal ulceration, a thickened, black area of the proximal oesophagus was discovered. Histopathology of the lesion revealed primary malignant melanoma. Although rare, primary melanoma can occur in noncutaneous locations.     

Minimally‐invasive plate osteosynthesis of a Salter‐Harris type 2 fracture of the proximal phalanx in a filly

A 7‐month‐old Warmblood filly was referred to the equine hospital because of a Salter‐Harris type 2 fracture of the proximal physis of the right hind P1. On admission, the filly had acute grade 3/5 lameness at the walk and diffuse swelling in the area of the right hind proximal phalanx. Radiographs were taken to assess the fracture and plan treatment. Surgical treatment using two 4.5 mm narrow locking compression plates (PIP‐LCPs) resulted in fracture stabilisation and rapid healing. This case report suggests that internal fixation using PIP‐LCPs is useful for the treatment of Salter‐Harris type 2 fractures of the proximal physis of P1 in large foals.     

Congenital oesophageal stricture in an Arabian filly treated by balloon dilation

Congenital oesophageal stricture was diagnosed via endoscopy in a 3‐day‐old Arabian filly suffering from nasal milk regurgitation. Vascular ring anomaly or other extramural, intramural or intraluminal causes were not identified on radiographs or on a computed tomography scan; thus a functional abnormality was suspected. The filly was treated with antibiotics for aspiration pneumonia and was fed milk through an indwelling nasoesophageal tube. Two sessions of balloon bougienage at the stenotic site, under sedation, resulted in marked clinical improvement and thereafter the filly was gradually reintroduced to suckling from the mare. The filly was discharged from the hospital after 17 days and on follow‐up there were no reports of food regurgitation even after the introduction of solid food. The filly was still doing well in the latest follow‐up at age 11 months.     

Surgical repair of a congenital lateral abdominal wall hernia in a neonatal foal

A 16‐hour‐old Quarter Horse filly presented for evaluation of a soft mass in the right caudoventral lateral abdominal wall. Radiography and ultrasonography confirmed the presence of a nonreducible lateral abdominal wall hernia with small intestine located between the skin and body wall. The size of the defect itself could not be imaged and the filly was taken to surgery. A 4 cm vertical defect that appeared congenital was found in the transverse abdominal muscle and was repaired by primary apposition. This case report describes the repair and outcome of this unusual type of congenital hernia.     

Facilitated ankylosis of a juvenile,flexurally deformed,open, luxated and infected metacarpophalangeal joint using an alternative approach

A 4‐day‐old Arabian filly was referred for severe lameness due to a flexurally deformed, open, luxated and infected metacarpophalangeal joint. Arthrodesis was indicated as progressive cartilage destruction and osteomyelitis developed. An alternative arthrodesis technique was employed, which consisted of a loop of cerclage wire running through predrilled holes in a lateromedial direction and dorsal to the central axis of the third metacarpal bone and proximal phalanx, in combination with external coaptation using a half‐limb transfixation cast. Ankylosis was radiographically confirmed after 4 weeks. The foal was discharged from the hospital with a grade 1 out of 5 lameness and a 6–7° valgus deviation of the ankylosed metacarpophalangeal joint. At telephone follow‐up after 18 months, the owner reported persistence of the valgus deviation, soundness at walk, and a slight gait irregularity at trot. The described cerclage wire arthrodesis technique is a relatively simple method for attaining ankylosis that could be considered in similar cases.     

Congenital bilateral aplasia of the metacarpophalangeal joints in a foal

A 2‐day‐old Warmblood filly was presented for examination of an angular limb deformity of the left front limb and an upright conformation of both metacarpophalangeal joints. Radiological examination revealed bilateral absence of the metacarpophalangeal joint space with fusion of the third metacarpal bone and first phalanx (synostosis). No treatment was undertaken. The filly was readmitted to the clinic 10 weeks later for bilateral front limb lameness. On radiological examination, the synostosis of the front metacarpophalangeal joints was still present. Physitis of the distal growth plate of the right third metacarpal bone and proximal growth plate of the right proximal phalanx, and an avulsion fracture of the palmaromedial and proximal aspect of the left middle phalanx, with a cystic like lesion on the medial aspect of distal first phalanx and proximal middle phalanx were diagnosed. Given the poor prognosis, the foal was subjected to euthanasia. Post mortem examination confirmed the absence of the metacarpophalangeal joint space with a trabecular bony union between the third metacarpal bone and the first phalanx. A rudimentary joint capsule was present at the level of the absent joints as well as a small zone of articular cartilage, which invaginated over a short distance into the dorsal trabecular bone on the right front limb. On the medial aspect of the left proximal interphalangeal joint, a focal defect of articular cartilage with exposure of subchondral bone was observed. This is the first case report of a foal born with congenital aplasia of both metacarpophalangeal joints. Congenital malformations should be considered as differential diagnosis in lame foals or foals born with angular or flexural limb deformities.     

Subconjunctival nodule due to Setaria equina erratic migration in a horse: First case report

An 18‐month‐old Arabian‐English filly resident in southwest France was referred for evaluation of a conjunctival mass in the right eye (OD). A pink, solid, and mobile nodular formation, measuring approximately 1.2 × 0.8 cm was found under the superior nasal bulbar conjunctiva during an ophthalmic examination that was otherwise normal. The mass was surgically removed using a standing procedure. Cytological examination of fine‐needle aspirates from the mass revealed a mixed eosinophilic‐lymphocytic inflammation. Histological examination confirmed the dense and diffuse eosinophilic‐lymphocytic infiltrate of the mass, and it revealed several cross sections of a parasitic nematode. The morphometric diagnosis identified an immature form of a filarial worm, and molecular analysis of the mitochondrial cytochrome c oxydase subunit 1 (cox1) and 12S rRNA gene sequences led to further identification of the specimen as Setaria equina. Microfilaremia was not observed on fresh blood smears. There have been no signs of local recurrence after 18 months, nor any evidence of intraocular involvement. To the authors’ knowledge, this is the first documented case of subconjunctival setariasis due to S equina in a horse.     

Successful management of multiple extrapulmonary complications associated with Rhodococcus equi pneumonia in a foal

This report describes the diagnosis and successful treatment of multiple extrapulmonary sequelae of Rhodococcus equi (R. equi) pneumonia in a 3‐month‐old filly. Bilateral uveitis and hyphaema, haemolytic anaemia and polysynovitis developed in this foal and were likely due to immune‐mediated mechanisms. The challenges associated with diagnosis and treatments of these extrapulmonary disorders are discussed. The filly was treated initially with clarithromycin and rifampin; however, a blood transfusion and immunosuppressive therapy with dexamethasone were required due to progressive haemolysis and for treatment of uveitis and polysynovitis. Bilateral hyphaema was successfully treated with intracameral injections of a recombinant tissue plasminogen activator. The development of antimicrobial resistance in R. equi was an additional challenge encountered in the management of this case and emphasises the importance of culture and in vitro antimicrobial susceptibility testing of isolates from foals with R. equi pneumonia. Extrapulmonary disorders associated with R. equi pneumonia are likely underdiagnosed and associated with a poor prognosis. This case highlights the importance of thorough and ongoing diagnostic assessment of foals with R. equi pneumonia and demonstrates that a successful outcome can be achieved with appropriate and directed treatment.     

Keratitis and periocular lesions associated with equine herpesvirus‐3 in a 3‐month‐old filly

A 3‐month‐old Quarter Horse filly presented with corneal ulceration in the right eye with extensive coalescing periocular ulcerations, erosions, and cutaneous crusts. Similar periocular lesions were present around the left eye, on the gingival mucosa, and on the cutaneous and mucosal surfaces of the lips. Based on the severity of the filly's corneal lesions, expense and duration of treatment, euthanasia was elected. Histological post mortem examination revealed numerous hyperplastic and/or dysplastic epithelial cells adjacent to areas of ulceration and erosion with intranuclear viral inclusion bodies. Equine herpesvirus‐3 (EHV‐3) was identified by polymerase chain reaction from the right cornea and lip. The virus was isolated from the right cornea, right eyelid and lip. The dam presented with multifocal to coalescing perineal vesicles. EHV‐3 was confirmed by polymerase chain reaction from the vulvar lesions and the mare recovered spontaneously. This is the first case of EHV‐3 corneal infection reported in horses and emphasises that EHV‐3 should be included as a differential diagnosis for vesicular lesions involving the equine periocular and oronasal epithelium.     

Multi-drug-resistant Enterococcus spp. as a cause of non-responsive septic synovitis in three horses

Abstract

CASE HISTORY: Three Thoroughbred horses, a 6-week-old filly (Case 1), a 15-year-old broodmare (Case 2) and a yearling filly (Case 3), sustained synovial sepsis secondary to trauma.

CLINICAL FINDINGS: Case 1 presented with a heel bulb laceration communicating with the distal interphalangeal joint. Arthroscopic lavage was performed and treatment commenced using systemic and local broad spectrum antimicrobial drugs. A pure growth of multi-drug-resistant (MDR) Enterococcus gallinarum was cultured from samples of synovium and joint fluid. Antimicrobial treatment was changed according to the susceptibility results. Response to treatment was poor and despite repeat arthroscopic lavage and intra-osseous regional perfusion of antimicrobials the filly was subject to euthanasia 24 days after the initial injury. Post-mortem examination confirmed septic synovitis, cartilage degeneration and osteomyelitis.

Case 2 sustained a full thickness wound to the carpus which was sharply debrided and closed. The wound dehisced with effusion within the tendon sheath. Drainage was established and treatment included systemic broad spectrum antimicrobials, topical lavage with povodine-iodine and manuka honey infusion. A mixed infection including MDR Enterococcus faecalis was cultured from the synovial fluid. Antebrachiocarpal joint effusion developed 21 days after initial injury and joint sepsis was confirmed. Arthroscopic lavage and tendon sheath debridement were performed, followed by treatment with systemic and local antimicrobials. The mare improved and was discharged. Three months later lameness recurred and corticosteroids were administered intra-articularly. The mare became non-weight bearing lame and was subject to euthanasia. Post-mortem examination confirmed joint sepsis of the antebrachiocarpal and intercarpal joint.

Case 3 presented with a complete articular open fracture of the tibial crest. Under general anaesthesia the fracture was stabilised and the wounds debrided and closed. Systemic broad-spectrum antimicrobials were administered. Six days later the wound dehisced and a bone fragment was removed. Three weeks post-surgery the wound deteriorated with a purulent discharge. Culture of the discharge revealed a mixed bacterial infection, including a MDR Enterococcus faecalis. Femoropatellar joint involvement was confirmed, and treatment included joint lavage, local and systemic antibiosis, and manuka honey instilled into the wound. The filly initially improved, and then deteriorated such that euthanasia was performed.

DIAGNOSIS: All three cases had synovial sepsis with MDR Enterococcus spp.

CLINICAL RELEVANCE: Increased awareness of MDR pathogens in equine wound infections is essential. Prompt diagnostic testing, appropriate therapy, infection control strategies and on-going monitoring and management are vital to limit the clinical impact of these organisms.     

Common variable immunodeficiency in a horse with chronic peritonitis

This report describes the clinical progression of a Quarter Horse filly with common variable immunodeficiency (CVID). Equine CVID is a primary immunodeficiency in which affected animals are unable to mount an appropriate antibody response and suffer recurrent bacterial infections. The filly in this report had a history of chronic respiratory tract infections but presented for assessment of poor weight gain and was diagnosed with Actinobacillus equuli peritonitis.     

Surgical management of an extrahepatic portosystemic shunt in a foal: A multidisciplinary problem

A 5‐week‐old American Miniature filly was referred due to intermittent neurological signs of 4 weeks' duration. Clinicopathological findings showed increased ammonia and bile acids in venous blood samples. Abdominal ultrasonography detailed a portosystemic shunt (PSS). The foal underwent laparotomy and operative mesenteric portovenography, which further defined the PSS as extrahepatic portocaval in configuration. The PSS was occluded and intraoperative portovenography confirmed successful shunt occlusion. The foal made a good recovery from surgery and had a successful showing career until she succumbed to colic just over 3 years after surgery.     

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.     

Diagnosis and management of Candida utilis infectious arthritis in a Standardbred filly

A 3‐year‐old Standardbred filly was admitted to the hospital for evaluation and management of previously diagnosed infectious arthritis of the right metacarpophalangeal joint (MCPJ). Candida utilis was isolated from multiple synovial samples submitted for bacterial culture and susceptibility. Following treatment with systemic and intra‐articular fluconazole and regional limb perfusion with amphotericin B and a second arthroscopic debridement the lameness improved and subsequent cultures were negative for bacterial or fungal growth. Infectious fungal arthritis should be a differential diagnosis for atypical or unresponsive joint infections especially in horses previously treated with a combination of intra‐articular corticosteroids and antibiotics.     

Lawsonia intracellularis proliferative enteropathy in a weanling foal,with a tentative histological diagnosis of lymphocytic plasmacytic enteritis

This Case Report describes a weanling filly with protein-losing enteropathy associated with Lawsonia intracellularis infection. This was diagnosed on the basis of a significant antibody response and a positive faecal PCR result. The histopathological lesion observed in proliferative enteropathy is mucosal hyperplasia, commonly affecting the ileum and colon in foals. Duodenal biopsies obtained from this filly revealed a lymphocytic plasmacytic infiltrate. The filly recovered completely following treatment with erythromycin and no additional medication was administered to treat the lymphocytic plasmacytic infiltrate. This Case Report suggests that lymphocytic plasmacytic infiltrates observed on duodenal biopsies may represent a nonspecific intestinal immune response.     

Computed tomography of nuchal ligament and semispinalis capitis tendon avulsions in a foal

Head trauma is a common injury in young horses. This case report describes a 10‐week‐old Thoroughbred foal with an open wound following trauma to the poll region, showing abnormal head carriage and depression. A computed tomography (CT) study was performed under general anaesthetic (GA). This identified a complete avulsion of the nuchal ligament (NL) and partial avulsions of the left and right semispinalis capitis (SS) tendons. Following diagnosis and conservative treatment the foal made a good recovery and 18 months later the filly had no detectable neurological or physical abnormalities. Computed tomography enabled an accurate and rapid diagnosis of a novel injury.     

IMAGING DIAGNOSIS — USE OF MULTIPHASE COMPUTED TOMOGRAPHIC UROGRAPHY IN THE DIAGNOSIS OF URETERAL TEAR IN A 6‐DAY‐OLD FOAL

A 6‐day‐old foal was evaluated for depression and inappetence. After initial stabilization, the filly developed a hypochloremic metabolic alkalosis and persistent hypercreatinemia. Abdominal ultrasound revealed fluid accumulation around the left kidney and a well‐defined rounded fluid filled structure dorsal to the urinary bladder. Computed tomography revealed a partial tear of the left ureter with distension of the retroperitoneal membrane. Exploratory celiotomy was performed to allow left kidney nephrectomy. At 6 months follow‐up, the filly was growing normally without complications. Ultrasound and CT imaging in this case provided an accurate diagnosis and a presurgical aid to select the appropriate therapeutic approach.     

Thoracic trauma and post operative lung injury in a neonatal foal

A 24‐hour‐old Standardbred filly was referred with an acute history of weakness, respiratory distress and subcutaneous emphysema. Radiographic evaluation revealed left sided rib fractures, unilateral pneumothorax and pneumomediastinum. Serial arterial blood gas measurements pre‐ and post rib repair showed pulmonary dysfunction. Post operative radiographs revealed the presence of air bronchograms and a bronchointerstitial pattern, suggestive of alveolar parenchymal pathology consistent with pulmonary contusion, pulmonary oedema or ALI/ARDS. The filly was treated with intranasal oxygen and an active chest draining unit and recovered uneventfully.