Spinal nephroblastoma in a crossbreed dog

A three-year-old, male crossbreed dog presented with progressive hindlimb paresis. Magnetic resonance imaging revealed an intramedullary spinal cord lesion of 1.5 cm diameter at the levels of the first and second lumbar vertebrae. Following surgical excision of the mass, there was resolution of the neurological signs. Twelve months later, hindlimb paresis was again evident. A second surgical procedure restored ambulatory status for a further five months before signs recurred and the dog was euthanased. A diagnosis of spinal nephroblastoma was made on the basis of signalment, lesion location and histopathological analysis of biopsy specimens.     

MAGNETIC RESONANCE IMAGING IN THE DIAGNOSIS OF LYMPHOMA INVOLVING THE BRACHIAL PLEXUS IN A CAT

An 11-year-old, neutered, female Domestic Long Hair cat had a 3-week history of left forelimb lameness. Conscious proprioception and postural reflexes were absent on the left thoracic limb. The cat had slightly reduced placing and hopping responses on the left pelvic limb, absent cutaneous trunci muscle reflex on the left side, and left triceps muscle atrophy. Magnetic resonance imaging revealed a 2 x 2 x 2 cm mass in the region of the left brachial plexus. The cat was treated by left forelimb amputation and hemilaminectomy. Histopathology of the brachial plexus revealed lymphoma.     

Septic arthritis,navicular bursitis and osseous cyst‐like lesion in a foal

The purpose of this report is to describe the clinical, imaging and pathological findings in a Quarter Horse colt admitted to the Texas A&M University Veterinary Medical Teaching Hospital for lameness of the left forelimb and left hindlimb. A presumptive diagnosis of left forelimb septic navicular bursitis was made ultrasonographically. A cyst‐like lesion of the calcaneus was diagnosed radiographically and better characterised with computed tomography. The cyst‐like lesion of the calcaneus was caused by infection with Actinobacillus sp. and extended into the adjacent tarsocrural, proximal intertarsal and talocalcaneal joints causing septic arthritis. The owner elected for euthanasia due to the poor prognosis. The diagnoses were confirmed on histopathology.     

Glenoid dysplasia and bicipital tenosynovitis in a Maine coon cat

This report describes a rare case of bicipital tenosynovitis in a Maine coon cat. The cat, a three-and-half-year-old neutered female, presented with chronic weightbearing lameness of the left forelimb. Flexion of the left glenohumeral joint and extension of the left cubital joint were resented, and palpation of the biceps brachii tendon in the bicipital groove elicited pain. A mild incongruity of the joint with mild degenerative changes was seen radiographically. Glenohumeral joint dysplasia was suspected. Ultrasound examination revealed marked thickening of the bicipital tendon and moderate effusion of the left bicipital tendon sheath. Positive contrast radiography of the joint confirmed dilation of the tendon sheath. A tentative diagnosis of bicipital tenosynovitis was made and confirmed on arthrotomy. Surgical removal of osteophytes resulted in the cat being free from pain but a mild lameness recurred six months after surgery.     

Metastatic phycomycosis in a horse

Extensive subcutaneous phycomycosis of the lower hindlimb developed over a period of 8 months in a Thoroughbred filly. There was no response to treatments such as trichlorphon, sodium iodide, or etisazole. Extension of the limb lesion over the following 3 months was associated with an enlarged inguinal lymph node, which was removed. Characteristic phycomycotic lesions were observed in the node, and a fungus having the morphologic features of Hyphomyces destruens was isolated from both the limb and nodal lesions.     

Medial collateral ligament desmitis of the distal interphalangeal joint in the hindlimb of a horse: treatment with cast immobilisation

A 12‐year‐old show‐jumping mare was presented for investigation of a chronic hindlimb lameness of 16 weeks duration. Perineural anaesthesia and ultrasonography localised the lesion to the medial collateral ligament of the distal interphalangeal joint of the left hindlimb. Treatment consisted of a heavily padded distal limb cast for 6 weeks, strict box rest and a strictly regulated hand walking program. Serial ultrasonographic examinations were performed throughout the rehabilitation period. Collateral ligament desmitis of the distal interphalangeal joint is a commonly diagnosed condition of the forelimb; however, hindlimb collateral ligament desmitis has been rarely reported. Ultrasonographic examination in this case was an invaluable diagnostic and follow‐up tool. Immobilisation of the foot by means of a heavily padded distal limb cast allowed excellent healing of the ligament and is presented as a novel treatment for collateral ligament desmitis. At the time of writing the mare had returned to her previous level of exercise and was showing no signs of lameness.     

Bilateral orbital and nasal aspergillosis in a cat

A 12-year-old, 4 kg, castrated male Persian cat was referred with a 2-month history of sneezing and bilateral mucopurulent nasal discharge. Rhinoscopically acquired nasal biopsies at this time revealed bilateral lymphoplasmacytic rhinitis. A tapering dose of oral prednisone caused the complete remission of the clinical signs, but 2 months after discontinuation of the therapy, the rhinitis recurred and the OD became exophthalmic. Computed tomography showed a soft tissue mass in both sides of the nasal cavity, both frontal sinuses, the right orbit, and to a lesser extent the left orbit. A fine needle aspirate of the right orbit revealed pyogranulomatous inflammation and Aspergillus spp. hyphae. Repeat nasal biopsy demonstrated multi-focal necrosis and a mixed inflammatory cell process which now included macrophages and scattered septate fungal hyphae. A few days later the cat became bilaterally blind and a contrast enhancing lesion involving the optic chiasm was found on magnetic resonance imaging. Despite a poor prognosis, therapy consisted of exenteration of the right orbit and trephination of both frontal sinuses before the planned initiation of medical antifungal therapy. Unfortunately, the cat died of cardiac arrest intraoperatively. Aspergillus fumigatus was cultured from both orbits at necropsy. Orbital aspergillosis has been rarely reported in cats and its relationship with lymphoplasmacytic rhinitis is unclear. In this patient lymphoplasmacytic rhinitis or previous antibiotic/corticosteroid therapy may have allowed secondary fungal invasion of the nasal mucosa and subsequently both orbits and the brain. Alternatively, Aspergillus infection may have preceded the lymphoplasmacytic rhinitis.     

Phaeohyphomycosis caused by Alternaria alternata in a cat

Phaeohyphomycosis caused by Alternaria alternata was diagnosed in a 6-year-old cat. A lesion in the nose resulted in enlargement of the dorsum of the nose. Similar appearing lesions had been removed from the dorsum of the nose 1 and 4 years earlier. The lesion recurred 3 months after surgical excision and irregular administration of ketoconazole. A second cytoreductive operation followed by 5 months' treatment with ketoconazole resolved the infection. Nasal trauma occurring at 8 months and at 5 years before initial examination may have predisposed the cat to development of the Alternaria infection.     

Gait analysis in a cat with scapular luxation and contralateral forelimb amputation

This report describes the use of a pressure-sensitive walkway to evaluate an uncommon case of a cat with dorsal luxation of the left scapula and an amputated right forelimb. The findings suggest that limb amputation induced load redistribution mostly to the contralateral forelimb despite the scapular luxation.     

Arthrodesis of the Equine Proximal Interphalangeal Joint: A Biomechanical Comparison of Two Parallel Headless, Tapered, Variable-Pitched, Titanium Compression Screws and Two Parallel 5.5 mm Stainless-Steel Cortical Screws

Objective— To compare the biomechanical characteristics, failure mode, and effects of side (left or right limb) and end (forelimb or hindlimb) of different screws in 2-screw, parallel-screw proximal interphalangeal joint arthrodesis constructs in horses.
Study Design— In vitro experimental study.
Sample Population— Twenty limbs from 6 cadavers (4 complete limb sets, 2 partial sets—total of 4 forelimb and 6 hindlimb pairs).
Methods— Two parallel 5.5 mm cortical (AO) screws were inserted in lag fashion in 1 randomly allocated limb of a pair, and 2 parallel headless, tapered, variable-pitched, titanium compression screws (Acutrak-Plus^®) were inserted in the contralateral limb. Constructs were tested in 3-point bending in a dorsopalmar (plantar) direction using a materials-testing machine at a loading rate of 5.83 mm/s. Maximal bending moment at failure and composite stiffness were calculated from data generated on load–displacement curves. Data were analyzed using a Friedman 2-way analysis of variance and Wilcoxon's signed-rank tests.
Results— No significant difference was detected for bending moment or stiffness values in proximal interphalangeal joint arthrodesis constructs using 2 parallel Acutrak-Plus^® or AO screws for fixation. Mean stiffness values were significantly different between forelimb and hindlimb constructs.
Conclusions— Performance of 2 parallel Acutrak-Plus^® screws was biomechanically comparable with 2 parallel AO 5.5 mm cortical screws in in vitro pastern arthrodesis constructs.
Clinical Relevance— Acutrak-Plus^® screws may provide an alternative means of fixation for proximal interphalangeal joint arthrodesis.     

Hypervitaminosis A in the cat: a case report and review of the literature

A case of hypervitaminosis A with secondary entrapment and compression of the left brachial plexus nerve roots is described. A 9-year-old male castrated domestic shorthair, fed a home-made diet based on raw pork liver, was submitted for examination for a left forelimb lameness that evolved to paralysis over a 2-month period. Clinical examination revealed a flaccid paralysis and atrophy of all left forelimb muscles. An ipsilateral Horner's syndrome was also noted. Radiological examination of the cervical and thoracic spine showed massive new bone formation at the ventral aspect of the second cervical to sixth thoracic vertebra. The diagnosis of hypervitaminosis A was made, based on the clinical and radiographic findings, as well as the determination of serum vitamin A concentration, which was 630 microg/dl, three times above the upper normal limit for this species. Despite the unfavourable initial prognosis, the cat progressively regained function of the affected limb approximately 6 months after the diet was changed to a commercial canned food.     

Acquired arachnoid cyst in a cat

A 5-year-old Birman cat presented with paraparesis associated with a fracture of the third thoracic vertebra and was managed conservatively. Voluntary function was regained over the next 6 months, but the cat was referred 4 years after the trauma because of recurrence of hindlimb paresis and ataxia. Magnetic resonance imaging (MRI) showed a spinal arachnoid cyst at the level of the fourth thoracic vertebra, which was treated surgically by dorsal laminectomy and durectomy, and hindlimb function subsequently recovered. The cat re-presented 4 years later for recurrent hindlimb paresis. Myelography and computed tomography–myelography (CT-M) showed dorsolateral pooling of cerebrospinal fluid (CSF) at the previous laminectomy site. The neurological signs after the second surgery improved, but not as much as after the first surgery and the cat remained ataxic with moderate paresis. Seven months later repeat CT-M revealed an atrophic spinal cord, but negligible pooling of CSF at the previous site of the arachnoid cyst. The cat could walk, but was being treated for self-induced trauma of the left hindlimb that was thought to be related to paraesthesia. The neurological signs gradually deteriorated over 3 months and the cat was euthanased.     

Localised Mycobacterium ulcerans infection in a cat in Australia

A 10-year-old castrated male domestic cat domiciled in eastern Victoria (Australia) was presented for a subcutaneous mass on its nasal bridge in November 2006. Cytological examination of an aspirate demonstrated pyogranulomatous inflammation. At surgery, the lesion consisted of an encapsulated mass containing viscid fluid. Histological examination of the resected lesion revealed pyogranulomatous inflammation surrounding a central zone of necrosis. Sections stained with the Ziehl-Neelsen method revealed numerous acid-fast bacilli, intracellularly within macrophages and extracellularly. Molecular studies established the infection was caused by Mycobacterium ulcerans. As histology demonstrated that the infection extended to the margin of the excised tissues, the cat was treated subsequently with clarithromycin (62.5mg orally once daily for 7 days, then twice daily for 3 months). The surgical wound healed unremarkably. The infection has not recurred at the time of writing, 1 year following discontinuation of treatment. Although M ulcerans infections have been recorded in variety of mammals, this is the first known case in a cat.     

Retracted: Mycobacterium bovis BCG Danish Strain 1331 isolated from a periarticular lesion in a domestic cat

A 7-year-old male neutered domestic shorthair outdoor cat was referred for chronic left forelimb lameness, which had been treated with intra-articular injections of triamcinolone acetonide. A soft tissue swelling around the elbow joint, extending from the distal humerus to the proximal ulna, was surgically explored and biopsy samples obtained. Mycobacterium bovis was cultured from samples from the soft tissue and bone. The mycobacteria from the media were killed and the DNA extracted and tested on a multiplex real-time PCR for the absence of specific genes and the presence of mycobacterial genus markers. The PCR revealed bacillus Calmette-Guérin Danish Strain 1331; this was also isolated from the prescapular lymph node, muscle and bone, obtained at post mortem examination. Badgers had been vaccinated with the bacillus Calmette-Guérin vaccine SSI (Statens Serum Institute) in the area where the cat lived, in the spring and autumn of the previous year. To the authors' knowledge, this is the first report of infection with M. bovis bacillus Calmette-Guérin Danish Strain 1331 in a domestic cat, potentially associated with annual vaccination of badgers in the proximity of the cat's home.     

A Quantitative Review of the Equinalysis System for Equine Locomotion Analysis

Movement analysis techniques allow objective and quantitative assessment of kinematic gait analysis. Consistent repeatability of the kinematic data is essential for such assessments. This study investigated whether the repeatability of a standardized Equinalysis Elite gait analysis system is sufficient to allow its use in clinical evaluation of equine lameness with reliable documentation of individual locomotion patterns. The extent to which examinations on different days affected the results when a standardized protocol was used was investigated. The repeatability of distal limb kinematics in nine sound horses over three successive days at one location was investigated. Measurements were performed at the examination area, for three motion cycles at the walk and trot, in each direction per day. Skin markers were placed on the lateral aspect of the coffin joint, forelimb fetlock joint, hindlimb fetlock joint, carpus, tarsus, elbow, and stifle, at clipped sites marked with a permanent marker. The inter-day repeatability of angular measurements of the carpus, tarsus, forelimb fetlock, and hindlimb fetlock joints was determined. A low degree of inter-day repeatability was found with statistically significant (P ≤ .05) differences between findings on different days, observed in the time-angle diagrams of left and right carpus, tarsus, forelimb fetlock, and hindlimb fetlock joints of all horses, at both walk and trot. The standardized Equinalysis Elite system for gait analysis of distal limb kinematics in the horse did not provide highly repeatable data in this setting.     

Giant cell tumor of the accessory carpal bone in a dog

A 4-year-old Springer Spaniel was referred because of a 6-week history of progressive left forelimb lameness. A marked pain response was elicited by palpation over the left accessory carpal bone. Radiography revealed a lytic, markedly expansile lesion of the accessory carpal bone. The bone was excised, and pancarpal arthrodesis was performed. Histologic examination of the excised bone revealed giant cell tumor. At 14 months after surgery, the dog was using the limb normally. Radiography of the carpus revealed satisfactory progression of the arthrodesis, and thoracic radiographs were negative for metastases.     

Chalastospora gossypii in a Maine Coon cat: case report and literature review

A 15-y-old castrated male Maine Coon cat was evaluated for an ulcerated soft tissue mass on the right hindlimb that had been observed for 4 mo and had grown rapidly. A 3 × 3 cm soft, raised, amorphous, and ulcerated subcutaneous mass was observed on the lateral right metatarsus. In-house cytology via fine-needle aspiration was nondiagnostic. Incisional biopsy of the mass and further staging was declined, and amputation was elected. The amputated limb was submitted for histopathology, which revealed severe chronic nodular granulomatous dermatitis and multifocal granulomatous popliteal lymphadenitis with large numbers of intralesional fungal hyphae. Fungal PCR and sequencing on formalin-fixed, paraffin-embedded tissue identified Chalastospora gossypii. No adjunctive therapy was elected at the time. The patient has done well clinically 1 y post-operatively. C. gossypii is a rare microfungus found worldwide and is considered a minor pathogen of several plants. To our knowledge, infection by this fungus has not been reported previously in veterinary species. Features in our case are comparable to other mycotic infections. Nodular granulomatous mycotic dermatitis and cellulitis, although uncommon, should be a differential for soft tissue masses in veterinary species; C. gossypii is a novel isolate.     

Cellulitis associated with coagulase-positive staphylococci in racehorses: nine cases (1975-1984)

Nine Thoroughbred racehorses were admitted with cellulitis (of one or more limbs) associated with coagulase-positive staphylococci. The right hindlimb was affected in 4 horses, the right forelimb in 2, the left hindlimb in 1, and both hindlimbs in 2. Typical abnormalities included high values for rectal temperature (9 horses) and heart rate (5 horses), hyperfibrinogenemia (7 horses), leukocytosis (7 horses), and neutrophilia (6 horses). The staphylococcal isolants were speciated in 3 horses and classified as Staphylococcus aureus. Complications included skin loss (5 horses), laminitis of the affected limb (2 horses), laminitis of the contralateral limb (4 horses), osteomyelitis and sequestrum formation (2 horses), and bacteremia (1 horse). Five horses were euthanatized because of the severity of the complications, ie, laminitis in 4 horses and severe skin loss in 1 horse. The remaining 4 horses were discharged from the clinic. At follow-up evaluation (mean, 16.7 months), the swelling in 3 of the horses had completely resolved. One horse returned to racing; of 2 used for pleasure riding, one was mildly lame. The remaining horse was not lame, but was used for breeding because of persistent swelling of the affected limb.     

Dorso-medial ante-brachiocarpal luxation with radio-ulna luxation in a domestic shorthair

An 8-year-old domestic shorthair was admitted with non-weight bearing left forelimb lameness. Examination and radiographs revealed dorso-medial ante-brachiocarpal luxation with palmar luxation of the distal radio-ulnar joint. Primary repair was performed and stabilised using an arthrodesis wire and type Ia Kirschner-Ehmer (K-E) external skeletal fixator (ESF). The cat regained excellent pain-free limb function by 14 weeks with only minor reduction in range of movement. This is the first case report of a cat with distal radio-ulnar joint luxation associated with ante-brachiocarpal luxation. Primary repair of carpal luxation in the cat should be considered before arthrodesis.     

Cutaneous pyogranuloma in a cat caused by virulent Rhodococcus equi containing an 87 kb type I plasmid

A 2-year-old intact male domestic shorthaired cat presented with a chronic, nodular, ulcerated, cutaneous lesion on the right thoracic limb. Histological and cytological examination revealed a pyogranulomatous inflammation with basophilic organisms in the macrophages. A virulent form of Rhodococcus equi containing an 87 kb type I (VapA) virulence plasmid was identified from cultures of biopsy samples. This report describes the clinicopathological features, plasmid profile and virulence of this case of R equi infection.