Diagnostic Imaging of Discospondylitis

Causal Agent Investigation and Treatment of Dogs Diagnosed with Discospondylitis in a Brucella canis Endemic Region

Discospondylitis is a well-recognized disease in dogs, but the relative prevalence of causal infectious agents and efficiency of relevant diagnostic tests are not well-established. Medical record review identified 117 dogs diagnosed with discospondylitis in our clinic over a 5-year period. In 32 dogs, discospondylitis was diagnosed as an incidental imaging finding; 24 of these dogs had concomitant neoplasia. A likely causal infection was identified in 45 of the remaining 85 dogs in which blood and urine cultures, serology for Brucella spp., and galactomannan fungal antigen testing were recommended. Ten dogs were diagnosed with Brucella canis, and ten were diagnosed with suspected fungal infection. Brucella suis serology was negative in all 35 dogs that were tested. Blood cultures were positive in 28 of 71 (39%) tested dogs, and urine culture was positive in 12 of 79 (15%). Cultures were positive from the lesion site of four of eight dogs that underwent surgery and one of the five dogs that underwent image-guided lesion sample collection. Subluxation secondary to discospondylitis was stabilized with metallic implants in four dogs. A similar proportion of known satisfactory treatment outcomes at last follow-up were recorded in dogs that had suspected fungal disease, other bacterial infections, or were Brucella-positive and in those dogs with imaging diagnosis only, although some individuals continued to receive anti-microbial agents or showed recurrent signs. These data support the value of blood culture in discospondylitis and suggest a relatively high prevalence of infection with Brucella spp. and suspected fungal infection.

Determining the prevalence and risk factors for positive bacterial culture in canine discospondylitis: 120 cases

BACKGROUND

Identification of the aetiologic agent in canine discospondylitis is infrequent; and risk factors for a positive bacterial culture have not previously been reported.

METHODS

Medical records at three institutions were searched to identify clinical features of dogs with discospondylitis diagnosed via radiography or cross-sectional imaging. Inclusion in this retrospective case-control study required culture of one or more samples. Multivariable binary logistic regression identified features associated with a positive culture.

RESULTS

Fifty (42%) of 120 dogs had one or more positive culture results obtained from either urine (28/115), blood (25/78), intervertebral disc aspiration (10/34) or cerebrospinal fluid (1/18). A positive culture was associated with higher bodyweight (p = 0.002, odds ratio [OR] = 1.054, 95% confidence interval [CI]: 1.019-1.089), more sample types cultured (p = 0.037, OR = 1.806, 95% CI: 1.037-3.147) and institution (p = 0.021). The presence of possibly associated preceding events (e.g., surgery), pyrexia, number of disc sites affected and serum C-reactive protein result, among other features, were not statistically significant.

LIMITATIONS

All isolates cultured were included since differentiation of true aetiologic agents from contaminants was not possible without histological confirmation and culture from surgical or postmortem biopsies.

CONCLUSIONS

Clinical features typically associated with infection were not identified as risk factors for positive culture in canine discospondylitis. The statistical significance of the institution suggests that standardisation of sampling protocols is necessary.

Clinical features, comparative imaging findings, treatment, and outcome in dogs with discospondylitis: A multi-institutional retrospective study

BACKGROUND

Limited recent data exists regarding discospondylitis in dogs.

HYPOTHESIS/OBJECTIVES

(i) Describe the signalment, clinical and imaging findings, etiologic agents, treatment, and outcome of dogs with discospondylitis, (ii) determine diagnostic agreement between radiographs, CT, and MRI with regard to the presence of discospondylitis and its location, and (iii) determine risk factors for relapse and progressive neurological deterioration.

ANIMALS

Three hundred eighty-six dogs.

METHODS

Multi-institutional retrospective study. Data extracted from medical records were: signalment, clinical and examination findings, diagnostic results, treatments, complications, and outcome. Potential risk factors were recorded. Breed distribution was compared to a control group. Agreement between imaging modalities was assessed via Cohen's kappa statistic. Other analyses were performed on categorical data, using cross tabulations with chi-squared and Fisher's exact tests.

RESULTS

Male dogs were overrepresented (236/386 dogs). L7-S1 (97/386 dogs) was the most common site. Staphylococcus species (23/38 positive blood cultures) were prevalent. There was a fair agreement (κ = 0.22) between radiographs and CT, but a poor agreement (κ = 0.05) between radiographs and MRI with regard to evidence of discospondylitis. There was good agreement between imaging modalities regarding location of disease. Trauma was associated with an increased risk of relapse (P = .01, OR: 9.0, 95% CI: 2.2-37.0). Prior steroid therapy was associated with an increased risk of progressive neurological dysfunction (P = .04, OR: 4.7, 95% CI: 1.2-18.6).

CONCLUSIONS AND CLINICAL IMPORTANCE

Radiograph and MRI results could be discrepant in dogs with discospondylitis. Prior trauma and corticosteroids could be associated with relapse and progressive neurological dysfunction, respectively.

Spinal decompression and stabilisation in a cat with lumbar vertebral pathological fracture and subluxation, following discospondylitis and spinal epidural empyema

Case series summary

A 1-year-old castrated male Maine Coon cat was referred because of a 1-week history of progressive spastic non-ambulatory paraparesis. An MRI examination of the thoracolumbar spine showed multiple lytic lesions, with the most aggressive one centred on the adjacent endplates of L1-L2 and its associated disc. Ventral new bone formation, L1 vertebral body shortening and mild dorsal displacement of the caudal aspect of L1 were noted. Contrast enhancement of both paravertebral soft tissue and extradural lesion was present. These findings were compatible with L1-L2 discospondylitis (DS), spinal epidural empyema (SEE), with secondary L1 pathological vertebral fracture, subluxation and spinal cord compression. CT of the thoracolumbar spine, abdomen and thorax confirmed these findings. The patient deteriorated to paraplegia with absent nociception, despite initial medical therapy. A right-sided L1-L2 hemilaminectomy and spinal decompression were then performed, followed by application of a unilateral construct comprising four smooth arthrodesis wires and polymethylmethacrylate (PMMA). Staphylococcus aureus was isolated from both epidural material, intraoperatively sampled and blood culture. Antibiotic therapy was continued for 6 weeks, based on susceptibility results. The outcome was excellent, with a gradual improvement and complete neurological recovery at the 8-week postoperative check. Repeated spinal radiographs showed an intact apparatus and marked signs of vertebral fusion. At the 14-month follow-up examination, the cat remained free of clinical signs.

Relevance and novel information

To the authors' knowledge, this is the first case report of SEE and DS in a cat that required surgical stabilisation. The outcome was still optimal, despite the rapid neurological deterioration.

Clinical infection of Brucella canis in a companion dog with discospondylitis in the Republic of Korea

A 2-year-old, spayed female, Bichon Frise dog was presented with reluctance to exercise, back pain, and frequent sitting down. Multiple osteolysis, periosteal proliferation, and sclerosis of the vertebral endplates of T11-13 were observed in the radiography, computed tomography, and magnetic resonance imaging. The bacterial culture of the urine specimen, the polymerase chain reaction (PCR) of the blood, and the antibody tests were positive for Brucella canis. Accordingly, discospondylitis caused by B. canis was diagnosed and doxycycline was administered. The clinical signs resolved and the culture and PCR results were negative afterwards. Doxycycline was discontinued after 6 months. The clinical signs recurred 2 weeks later, and the combination treatment of doxycycline and enrofloxacin was initiated. Though no clinical signs were observed after 9 months and the bacterial cultures and PCR were negative, the antibody titre remained at 1 : 200 or more. The dog will continue taking antibiotics until the antibody titre drops. To the best of our knowledge, this is the first case report of a clinical infection of B. canis associated with canine discospondylitis in the Republic of Korea. Although the clinical signs of brucellosis might improve with antibiotic treatment, the disease cannot be cured due to Brucella's various strategies to evade host immune systems. Specifically, it can proliferate and replicate within the host cells, resulting in an environment that makes treatment less effective. Furthermore, owing to its zoonotic potential, owners and veterinarians should consider lifelong management or euthanasia.

Prevalence and Features of Incidental Findings in Veterinary Computed Tomography: A Single-Center Six-Years' Experience

Computed tomography (CT) is an advanced imaging technique that may lead to detect "incidentalomas", unexpected asymptomatic lesions found during unrelated examinations. Their clinical meaning and management are not clear for veterinarians, who risk unnecessary investigations that harm the patients. This study is a retrospective analysis that aims to investigate incidentalomas in CT exams and to describe their prevalence, location, types and follow-up, their correlations and associations with the species, breed, sex, and age of patients examined and with the kind and number of sites scanned. The reports of 561 CT scans performed in 512 dogs and 49 cats in a veterinary facility over six years were reviewed and compared to the clinical records of the patients. Eighty incidentalomas were found in 57 dogs and four cats. A significant positive correlation was found in dogs between age and the prevalence of incidentalomas. In dogs, the prevalence of incidentalomas was significantly higher in Boxers and in neck, thoracic, and abdominal scans. Spinal incidentalomas were the most common typologies in dogs. This study can represent a tool that allows clinicians to acquire greater awareness about incidentalomas and to carry out the evidence-based clinical management of them.

Imaging techniques in veterinary medicine. Part II: Computed tomography, magnetic resonance imaging, nuclear medicine

Radiography and ultrasonography are the most used techniques in veterinary clinical practice, due to organizational, managerial and, mostly, economic reasons. However, in the last decades, Computed tomography (CT), Magnetic Resonance Imaging (MRI) and, to a lesser extent, Nuclear Medicine (MN) are increasingly used. As we said in the previous article, all the Diagnostic Imaging techniques are actually "indispensable" in Veterinary Medicine, where many patients do not show any symptoms.This second part describes Computed Tomography (CT), Magnetic Resonance (MRI) and Nuclear Medicine techniques in Veterinary Medicine are described.

Microbiological aspects of osteomyelitis in veterinary medicine: drawing parallels to the infection in human medicine

Osteomyelitis is a challenging infectious disease affecting humans and animals. It is difficult to diagnose because, in many cases, symptoms are non-specific and, for example in implant-related cases, can appear long time after surgery. In addition to this, it is also difficult to treat due to the need to find the appropriate antibiotic regime and delivery system to reach the site of infection and to avoid development of bacterial resistance. The central purpose of this review is to compare the microbiological aspects of osteomyelitis in human and veterinary medicine, with the aim of improving the microbiological diagnosis and treatment of this infection in animals. Furthermore, the study of osteomyelitis in animals may help to improve the development of animal models for testing new treatments in humans. Host factors and underlying conditions have been studied mainly in humans, although aspects as immunodeficiency have been described in some veterinary cases. Even when Staphylococcus aureus is still considered the most prevalent causing microorganism, this prevalence should be reviewed using molecular diagnostic techniques, and this could affect treatment options. New approaches to treatment include local delivery of antibiotics using different biomaterials, antimicrobial photodynamic therapy, and new antimicrobial compounds. We would like to remark the need of large, high-quality clinical trials and of the development of guides for the diagnosis and treatment of osteomyelitis in different animal species.

Brucella canis discospondylitis in 33 dogs

Objective

To describe the clinical and imaging findings of 33 dogs with Brucella canis discospondylitis (BDS).

Animals

33 client owned dogs from four veterinary specialty hospitals within Colorado and Arizona with at least one positive B. canis test and spinal diagnostic imaging.

Procedures

Retrospective review of signalment, physical and neurological examination findings, laboratory results, B. canis serology, and diagnostic imaging of 33 dogs with BDS. All imaging was reviewed by a board-certified veterinary neurologist. Radiographs were reviewed by a board-certified veterinary radiologist blinded to MRI and CT findings.

Results

31/33 (94%) dogs were <5 years old (median = 2.5 years, mean = 2.9 years, range 0.5–10 years). 21/29 (72%) dogs had signs of nonspecific pain, spinal pain, or lameness for >3 months (median = 6 months, mean = 8.2 months, range 5 days−4 years). Fever was seen in only 4/28 (14%) dogs. Multifocal lesions were evident on radiographs in 21/29 (72%) dogs and MRI in 12/18 (67%) dogs. Smooth, round, central end-plate lysis, defined as “hole punch” lesions, were identified radiographically in 25/29 (86%) dogs. Vertebral physitis or spondylitis without discitis was evident on MRI in 7/18 (39%) dogs.

Clinical relevance

Dogs with BDS typically present at a young age with a long duration of clinical signs. Identification of radiographic “hole punch” lesions and MRI evidence of vertebral physitis, spondylitis, and paravertebral inflammation without discitis should increase suspicion for BDS. BDS may be increasing in frequency in the southwestern United States, and dogs with signs of chronic spinal pain and/or lameness should be screened for B. canis.

Computed tomography features of discospondylitis in dogs

BACKGROUND

Computed tomography (CT) findings of dogs with discospondylitis have not been widely described despite increased availability of this imaging modality.

OBJECTIVES

Describe the CT features of discospondylitis in a population of clinically affected dogs with discospondylitis diagnosed by magnetic resonance imaging (MRI).

ANIMALS

Forty-one dogs (63 affected discs) with MRI-identified discospondylitis presented to a single referral hospital between 2012 and 2022.

METHODS

Retrospective, single center, descriptive case series with analysis of MRI-identified discospondylitis sites and concomitant CT imaging. Computed tomographic features of MRI-affected sites including intervertebral disc space (IVDS), endplates, vertebral body, epidural space and paraspinal tissues were described.

RESULTS

The most frequently found changes were: (1) endplate involvement (87.3%) most frequently bilateral (94.5%), with erosion (61.9%) and multifocal osteolysis (67.3%); (2) periosteal proliferation adjacent to the IVDS (73%) and spondylosis (66.7%); and (3) vertebral body involvement (66.7%) involving one-third of the vertebra (85.7%) with multifocal osteolysis (73.5%). Other less prevalent features included an abnormal IVDS (narrowed or collapsed), sclerosis of the adjacent vertebral body or endplates, presence of disseminated idiopathic skeletal hyperostosis or vacuum artifact.

CONCLUSIONS AND CLINICAL IMPORTANCE

We determined that bilateral endplate erosion and periosteal proliferation were very common in dogs with discospondylitis. Careful evaluation of CT in all 3 planes (dorsal, sagittal, transverse) is necessary to identify an affected IVDS. These described CT features can aid in the diagnosis of discospondylitis in dogs but equivocal cases might still require MRI.

Canine brucellosis in three littermates, case report

Three adult littermates were diagnosed with Brucella canis, two of which were diagnosed with discospondylitis. The first littermate, a 2-year-old spayed-female Labrador Retriever, was evaluated for progressive episodes of cervical pain, lethargy, reported circling to the right, and a right-sided head tilt. Magnetic resonance imaging (MRI) of the cervical spine revealed changes consistent with discospondylitis at C6-C7. MRI of the brain was unremarkable and cerebrospinal fluid analysis was declined. Brucella spp. was isolated from aerobic and Brucella blood cultures. PCR performed on the isolate identified Brucella canis and indirect fluorescent antibody (IFA) testing for Brucella canis also confirmed the species. Patient #1 was treated with doxycycline and marbofloxacin for 1 year. Clinical signs returned 2-years after diagnosis. Following the diagnosis of patient #1, a known littermate (patient #2) was tested for Brucella canis. Patient #2 was 2 years old and asymptomatic at the time of diagnosis. Aerobic and Brucella spp. cultures, PCR, and IFA were obtained and were diagnostic for Brucella canis. A 6-month course of marbofloxacin and doxycycline was implemented. The patient remained PCR positive following 4 months of treatment and repeat cultures were planned following 6 months of treatment; however, the patient was lost to follow-up. A third littermate (patient #3) was identified by the family of patient #1. Patient #3 was evaluated at 18 months of age for a 6-month history of progressive lumbosacral pain. Spinal radiographs revealed discospondylitis of the C3-C4, T12-T13, and L7-S1 vertebral endplates. Computed tomography (CT) of the lumbosacral spine was also consistent with discospondylitis at L7-S1. Brucella canis serologic testing consisting of rapid slide agglutination test, 2ME-rapid slide agglutination test, and cytoplasmic agar gel immunodiffusion was positive. Enrofloxacin was administered for 7 months and was discontinued thereafter based on radiographic evidence of healing and resolution of clinical signs. Although Brucella canis is not a rare disease in dogs, the documentation of two out of three adult littermates with associated discospondylitis is an interesting feature. In addition, this report highlights available diagnostic and treatment options, as each patient was managed differently based on clinical signs and the preference of the managing clinician.

Bayesian clinical reasoning in the first opinion approach to a dog with suspected thoracolumbar pain

Whilst multi-planar imaging has allowed advances in diagnosis and treatment of canine spinal cord disorders, it is sometimes inaccessible to pet owners leading to a reliance on imaging modalities and ancillary tests that are more readily available. For this reason, this essay considers how Bayesian clinical reasoning may aid in deciding which tests, if any, are most useful for the diagnosis of spinal disease in clinical practice and choosing reasonable empiric therapies.

Retrospective Preliminary Assessment of Routine Follow-Up Low-Field Magnetic Resonance Imaging in Dogs Presumptively Diagnosed With Discospondylitis

Background

The usefulness of routine follow-up Magnetic Resonance Imaging (MRI-2) in asymptomatic dogs treated for discospondylitis is unknown.

Methods

This cross-sectional retrospective study investigated the features of MRI-2 in a heterogeneous group of dogs treated for discospondylitis, and if these were associated with the presence or absence of clinical signs. After comparing initial MRI (MRI-1) and MRI-2, an observer, blinded to the dog's clinical signs, described the MRI-2 findings. The study population was then divided into symptomatic or asymptomatic at the time of MRI-2. Two separate observers subjectively classified the discospondylitis as active or inactive. Repeatability and interobserver agreement were evaluated.

Results

A total of 25 dogs were included. At the time of MRI-2 16 (64%) dogs were asymptomatic and 9 (36%) were symptomatic. Based on MRI-2, 20 (80%) and 18 (72%) out of 25 dogs were considered to have active discospondylitis by the first and second observers, respectively. Interobserver agreement was moderate. No MRI-2 features were associated with the clinical status. The subjective classification of inactive discospondylitis was significantly associated with asymptomatic clinical status, but the classification of active discospondylitis was evenly distributed between groups.

Conclusion

This study did not identify a meaningful association between the clinical status of dogs treated for presumptive discospondylitis and MRI-2 results. There were no specific MRI-2 features which were associated with the clinical status.

Comparison of computed tomography and surgical findings and investigation of their associations with outcomes for dogs with sublumbar abscesses

OBJECTIVE

To describe and compare the results of preoperative CT and surgical findings in dogs with sublumbar abscesses and investigate potential associations between these variables and the outcome of abscess recurrence.

ANIMALS

51 client-owned dogs.

PROCEDURES

A retrospective, records-based study was performed of dogs undergoing surgery for treatment of sublumbar abscesses diagnosed by use of CT between January 2010 and December 2018. Signalment, clinical signs, clinicopathologic data, CT findings, surgical techniques and findings, duration of hospitalization, postoperative treatment, and complications were recorded. Long-term follow-up was performed through telephone interviews. Logistic regression analysis was used to investigate associations between the variables of interest and abscess recurrence.

RESULTS

51 dogs met the study inclusion criteria; 48 were included in outcome analysis. The CT findings agreed with surgical findings for identification of a migrating vegetal foreign body for 39 of 51 (77%) dogs. All dogs survived to hospital discharge; 1 dog died of hemoabdomen 3 days after surgery, and 6 had minor (surgical wound) complications reported. Abscess recurrence developed in 12 of 48 (25%) dogs with a median time to recurrence of 6 months. Identification of diskospondylitis on CT examination was the only investigated factor significantly associated with recurrence; odds of recurrence in dogs with this finding were 8.4 times those for dogs without this finding.

CONCLUSIONS AND CLINICAL RELEVANCE

Our results suggested dogs with sublumbar abscesses have a good prognosis after surgery, although recurrence can develop. Preoperative identification of diskospondylitis was significantly associated with abscess recurrence in this study sample.

Low-field magnetic resonance imaging characteristics of multifocal vertebral lesions in dogs

BACKGROUND

There is a lack of information regarding magnetic resonance imaging (MRI) features of polyostotic vertebral lesions in dogs. The aim of this retrospective study was to identify and differenciate low-field MRI features of aggressive versus benign multifocal vertebral diseases in dogs.

METHODS

MRI examinations from 49 dogs with polyostotic vertebral lesions were reviewed. Images were evaluated for vertebral intensity changes, expansile lesions, new bone formation, cortical bone interruption, paravertebral musculature changes, lymphadenomegaly, spinal cord compression and spinal cord signal changes.

RESULTS

Twenty-nine dogs with non-aggressive bone lesions and 20 dogs with aggressive vertebral lesions were included. Non-aggressive lesions had variable T2-weighted fast spin-echo (T2W) signal intensity and the majority displayed low signal intensity on short tau inversion recovery (STIR). Aggressive lesions predominantly had high T2W and STIR signal intensity, with variable signal intensity on T1-weighted spin-echo and contrast enhancement. Aggressive lesions were associated with spinal pain (p < 0.01), new bone formation (p = 0.02), spinal cord compression (p < 0.01) and lymphadenomegaly (p < 0.01). Cortical interruption (p < 0.01) and paravertebral musculature changes (p < 0.01) were the strongest indicative imaging features for aggressive lesions.

CONCLUSION

Spinal pain, spinal cord compression, new bone formation, lymphadenomegaly and especially cortical interruption and paravertebral musculature signal intensity changes were the best discriminators for differentiating malignant from benign vertebral lesions.

Vertebral fracture due to Actinobacillus pleuropneumoniae osteomyelitis in a weaner

BACKGROUND

Osteomyelitis is relatively frequent in young pigs and a few bacterial species have been postulated to be potential causative agents. Although Actinobacillus (A.) pleuropneumoniae has been sporadically described to cause osteomyelitis, typically, actinobacillosis is characterized by respiratory symptoms. Nevertheless, subclinical infections are a challenging problem in pig herds. To the authors' knowledge, this is the first case description that reports clinical, diagnostic imaging, pathological and histopathological findings of vertebral osteomyelitis in a pig and first describes A. pleuropneumoniae as the causative agent identified by advanced molecular methods.

CASE PRESENTATION

An eight-week-old female weaner was presented with a non-ambulatory tetraparesis. The neurological signs were consistent with a lesion in the C6-T2 spinal cord segments. Imaging studies revealed a collapse of the seventh cervical vertebral body (C7) with a well demarcated extradural space-occupying mass ventrally within the vertebral canal severely compressing the spinal cord. Post-mortem examination identified an abscess and osteomyelitis of C7 and associated meningitis and neuritis with subsequent pathological fracture of C7 and compression of the spinal cord. In the microbiological analysis, A. pleuropneumoniae was identified using PCR and DNA sequence analysis.

CONCLUSIONS

A. pleuropneumoniae can be responsible for chronic vertebral abscess formation with subsequent pathological fracture and spinal cord compression in pigs.

C-reactive protein in dogs with suspected bacterial diskospondylitis: 16 cases (2010-2019)

Objectives

C-reactive protein (CRP) is an acute phase protein used in multiple canine inflammatory conditions including steroid responsive meningitis-arteritis, immune-mediated polyarthritis and bronchopneumonia. The aim of this study was to assess whether serum CRP is elevated in cases of diskospondylitis.

Methods

Medical records from 2010 to 2019 were searched to identify dogs diagnosed with diskospondylitis based on findings consistent on CT or MRI and with CRP tested.

Results

A total of 16 dogs met the inclusion criteria. All cases had back pain. Fourteen cases had elevated CRP, with a median value of 100.7 mg/l (reference range for CRP values: 0-10 mg/l), 12 were pyrexic and six had leucocytosis. The two dogs with normal CRP were normothermic and did not have leucocytosis. CRP was measured four to six weeks into antimicrobial treatment in eight of 14 dogs and was normal in all cases. One dog developed a suspected bacterial empyema diagnosed on MRI; this occurred two weeks after antibiotic treatment was discontinued based on a normal CRP level at follow-up.

Conclusions

Serum CRP is elevated in cases of diskospondylitis and may be clinically more useful to screen dogs with back pain than pyrexia or leucocytosis alone. Further long-term clinical evaluation in a prospective study is needed to assess its use as a treatment monitoring tool and in decision making.

Imaging features of discospondylitis in cats

OBJECTIVES

This study describes the imaging features of feline discospondylitis on MRI, comparing them with CT and radiographic findings where available.

METHODS

The medical records of cats diagnosed with discospondylitis, presented to three referring institutions, were reviewed. MRI, CT and radiographic features were assessed by two of the authors independently.

RESULTS

Fourteen sites of discospondylitis were retrospectively identified in 13 cats. The L7-S1 intervertebral disc space (IVDS) was affected in 7/14 (50%) cases. Characteristic MRI features included a hyperintense nucleus pulposus signal on T2-weighted (T2W) imaging (n = 10/14 [71%]) and short tau inversion recovery (STIR) imaging (n = 11/13 [85%]), with contrast enhancement in all (n = 11/11); involvement of adjacent vertebral endplates (n = 11/14 [79%]) and hyperintense neighbouring soft tissue on T2W (n = 11/14 [79%]) and STIR (n = 10/13 [77%]), with contrast enhancement in all (n = 11/11); and the presence of spondylosis deformans (n = 10/14 [71%]). Other features included narrowed or collapsed IVDS (n = 8/14 [57%]), contrast enhancement of vertebral bodies (n = 5/11 [46%]), epidural space involvement (n = 5/14 [36%]), compression of the spinal cord or nerve roots (n = 5/14 [36%]), paraspinal abscessation (n = 3/14 [21%]) and meningeal signal intensity abnormalities with contrast enhancement (n = 5/6 [83%]). These latter findings may indicate secondary focal meningitis. Radiographs were available covering five sites (in four cats) and CT covering three sites (in two cats). The most common radiological features were collapse or narrowing of the affected IVDS (80%) and endplate erosion (60%). No changes suggestive of discospondylitis were identifiable on radiography or CT in two sites (one cat), despite being identifiable on MRI. Repeated radiography in one case did not reveal complete radiological resolution following 9 months of treatment.

CONCLUSIONS AND RELEVANCE

The results of this study indicate consistent MRI features of feline discospondylitis that should be considered in the diagnosis of this condition.

Multicentric Septic Osteomyelitis and Arthritis Caused by Staphylococcus aureus in a Gyrfalcon (Falco rusticolus)

An adult female gyrfalcon (Falco rusticolus) was presented with a right-wing droop and weight loss. Radiographic images revealed osteolysis and osseous proliferation of the right shoulder and the mobile vertebra between the notarium and synsacrum. The tentative diagnosis was vertebral osteomyelitis secondary to septic arthritis. The bird did not respond to antibiotic and anti-inflammatory therapy and represented 10 days later, with feathers soiled with feces, an impacted, dilated cloaca, and an inability to stand due to spastic paralysis of the hind legs. The bird's condition did not improve with 24 hours of supportive care and its quality of life was considered poor; therefore, the patient was euthanatized and submitted for postmortem examination. Multicentric septic osteomyelitis and arthritis were confirmed in the mobile vertebra between the notarium and synsacrum and the right shoulder. Despite 10 days of antibiotic therapy, Staphylococcus aureus was isolated from within the 2 locations in which septic osteomyelitis and arthritis were identified. This report describes the clinical features, diagnosis, and pathologic findings of septic osteomyelitis and arthritis caused by S aureus in a falcon.

Canine Brucellosis: Insights Into the Epidemiologic Situation in Europe

Brucella canis is one of many responsible pathogens of discospondylitis in dogs and infections require specific management. Little is known about the epidemiologic situation in Europe. The purpose of the study was to get insights into the occurrence of brucellosis in dogs in Europe. The database of a European veterinary laboratory was screened for Brucella positive samples. Additionally, medical records of a veterinary hospital in Germany were screened for diagnosis of discospondylitis and brucellosis. The laboratory received samples from 20 European countries for Brucella testing in dogs: 3.7% of submitted samples were Brucella spp. PCR-positive (61/1,657), and Brucella canis antibodies were identified in 5.4% of submitted samples (150/2,764). Brucella spp. PCR-positive samples originated from Spain (11.1% of submitted samples), Poland (6.7% of submitted samples) and rarely from Italy and France. Samples with Brucella canis antibodies originated from 13 European countries (Sweden, Belgium, Austria, Switzerland, Italy, Finland, Germany, Denmark, Hungary, Norway, Poland, France, Netherlands). Young dogs (0–24 months) had a 5.4-fold increased risk of PCR positive samples. The supplementary medical records search identified four young female dogs (7–30 months) with Brucella canis discospondylitis in Germany. The four dogs had been imported to Germany from Eastern European countries (Moldavia, Romania, Macedonia). In conclusion, infection with Brucella canis needs to be considered in dogs in Europe and diagnostics for Brucella canis infection appear indicated in young dogs with discospondylitis.