Osteoarthritis in cats: a retrospective radiological study

OBJECTIVES: To provide basic information about natural feline osteoarthritis (OA) as part of more extensive studies. METHODS: A retrospective study of cats (greater than one year of age) radiographed for any reason at a first opinion and referral veterinary practice was performed. Cats were classified as either having or not having radiographic OA. Computerised histories were searched for records of potential causes and clinical signs of OA. The genders and ages of the affected cats were compared with a control population using chi-squared tests. RESULTS: Of 491 cats, 292 (59 per cent) had undergone a diagnostic radiograph of at least one synovial joint. Sixty-three of 292 cats (22 per cent) showed evidence of radiographic OA; 21 (33 per cent) of which also had clinically evident OA. A potential cause of OA had been recorded in only seven of 63 cats (11 per cent). The population of cats with radiographic evidence of OA was older than the control population (P<0.001). CLINICAL SIGNIFICANCE: Radiographic OA was found in 22 per cent of the test population. In many cases there was no clinical evidence of OA recorded in the history, suggesting that either there is little correlation between clinical and radiographic OA or that clinical signs of OA in cats may not have been observed or recorded. Idiopathic/primary OA was common.     

Feline osteoarthritis: a prospective study of 28 cases

OBJECTIVES: To identify a cohort of cats with clinical osteoarthritis and to report on the clinical signs, the frequency of joints affected and the possible aetiopathogenesis within this population. METHODS: Inclusion criteria for this prospective study were presence of historical evidence and/or clinical signs of osteoarthritis, together with radiographic evidence of osteoarthritis. Patients showed clinical improvement within four weeks of analgesic administration and were free from other disease processes, which might explain the clinical signs and/or their response to analgesia. RESULTS: Twenty-eight cases were included in the cohort. The elbow (45 per cent) and the hip (38 per cent) were the most frequently affected joints. Seventy-one per cent of cases had primary/idiopathic aetiology. Alterations in both the ability to jump (71 per cent) and the height (67 per cent) of jump (lifestyle changes) were the most frequent signs of disease. Sixty-one per cent of owners felt that their pet had made a marked improvement following administration of an analgesic/anti-inflammatory drug. There were statistically significant improvements in the ability to jump (P < 0.001), the height of jump (P < 0.001), lameness (P = 0.03), stiff gait (P = 0.04) and the activity level (P = 0.02) when compared with the start and the end of the study period. CLINICAL SIGNIFICANCE: Osteoarthritis is a clinical problem in cats, but overt lameness is not the most common clinical feature.     

Cross-sectional study of the prevalence and clinical features of osteoarthritis in 100 cats

To assess clinical signs and relevance of osteoarthritis (OA) in cats, the radiographic prevalence of OA in the appendicular skeleton of 100 client-owned cats (?6 years old) was assessed. Possible associations between radiographic OA, clinical locomotor system examination, and owner-perceived behavioural changes were evaluated. OA was most prevalent in the shoulders, elbows, hips and tarsal joints with 61% of cats having OA in at least one joint and 48% in more than one joint. Overall, clinical examination of the larger peripheral joints had the highest sensitivity and specificity for radiographic OA. Regression analysis showed age to be related to OA (P = 0.002), as were decreased mobility and grooming (P = 0.008), although there was a correlation with age. Finally, increased inappropriate elimination was associated with OA (P = 0.046). It was concluded that the prevalence of OA in cats is strikingly high and increases with age. OA in cats seems to be associated with behavioural changes.     

Cross‐Sectional Study of the Prevalence of Radiographic Degenerative Joint Disease in Domesticated Cats

Objective: To determine the prevalence of radiographic signs of degenerative joint disease (DJD) in a randomly selected sample of domestic cats. Study Design: Prospective observational study. Animals: Client‐owned cats. Methods: Cats (n=100) from a single practice and equally distributed across 4 age groups (0–5; 5–10; 10–15, and 15–20 years old) were randomly selected (regardless of heath status) and sedated for orthogonal radiographic projections of all joints and the spine. Quasi‐Poisson regression analysis was used to investigate the relationship between patient demographics, blood biochemistry, hematologic and urine analysis variables, and DJD severity. Results: Most (92%) cats had radiographic evidence of DJD; 91% had at least 1 site of appendicular DJD and 55% had ≥1 site of axial column DJD. Affected joints in descending order of frequency were hip, stifle, tarsus, and elbow. The thoracic segment of the spine was more frequently affected than the lumbosacral segment. Although many variables were significantly associated with DJD, when variables were combined, only the association between age and DJD was significant (P<.0001). For each 1‐year increase in cat age, the expected total DJD score increases by an estimated 13.6% (95% confidence interval: 10.6%, 16.8%). Conclusion: Radiographically visible DJD is very common in domesticated cats, even in young animals and is strongly associated with age. Clinical Relevance: DJD is a common disease of domesticated cats that requires further investigation of its associated clinical signs.     

Prevalence of feline leukaemia virus and antibodies to feline immunodeficiency virus in cats in the United Kingdom

A representative sample of the pet cat population of the United Kingdom was surveyed. Blood samples from 1204 sick and 1007 healthy cats of known breed, age and sex were tested for antibodies to feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV). The prevalence of FIV was 19 per cent in sick cats and 6 per cent in healthy cats, and the prevalence of FeLV was 18 per cent in sick cats and 5 per cent in healthy cats; both infections were more common in domestic cats than in pedigree cats. Feline immunodeficiency virus was more prevalent in older cats but FeLV was more prevalent in younger cats. There was no difference between the prevalence of FeLV in male and female cats but male cats were more likely to be infected with FIV than female cats. No interaction was demonstrated between FIV and FeLV infections. Of the cats which were in contact with FIV in households with more than one cat, 21 per cent had seroconverted. The prevalence of FeLV viraemia in cats in contact with FeLV was 14 per cent. The clinical signs associated with FIV were pyrexia, gingivitis/stomatitis and respiratory signs, and with FeLV, pyrexia and anaemia. It was concluded that both viruses were significant causes of disease, and that the cats most likely to be infected with FIV were older, free-roaming male cats and for FeLV, younger, free-roaming cats.     

Neuropathological findings in cats with clinically suspect but histologically unconfirmed feline spongiform encephalopathy

Central nervous system (CNS) tissues from 192 cats with neurological signs were examined histologically, and tissues from 173 of them were later examined immunohistochemically as part of a survey to determine the prevalence of feline spongiform encephalopathy (FSE). One of the cats was from Norway and the others were from Great Britain. The most commonly recorded clinical signs were ataxia, behavioural changes and epilepsy, but none of the cats had histopathological evidence of FSE. The most common organic CNS lesions were non-suppurative encephalomyelitis in 28 per cent, neoplasia in 15 per cent and a heterogeneous group of degenerative encephalopathies in 9 per cent of the cats. A range of minor histological lesions of uncertain significance was also observed. No histological lesions were observed in the tissues of 63 (33 per cent) of the cats. Disease-specific prion protein (PrP(Sc)) was observed in only one of the 173 cats examined by immunohistochemistry.     

Fusion of the distal intertarsal and tarsometatarsal joints in the horse using intraarticular sodium monoiodoacetate

Six normal horses received 3 intra-articular injections of sodium monoiodoacetate (MIA) in the distal intertarsal (DIT) and tarsometatarsal (TMT) joints of one hindlimb. Injections were at three week intervals, and post injection pain was controlled with routine administration of phenylbutazone for five days following each injection. All horses underwent a gradually increasing exercise programme consisting of walking and trotting beginning one week after the first injection and continuing for 24 weeks. All treated joints showed increasingly severe radiographic evidence of degenerative joint disease with time. Clinical signs were mild or absent during exercise. All treated joints showed radiographic and histological evidence of fusion 24 weeks after the first injection. Amount of radiographic fusion ranged from 54.49 per cent to 88.64 per cent of the joint space. Histologically, the joint space that appeared radiographically fused was filled mainly with woven and lamellar bone. Fibrocartilage and fibrous tissue was seen frequently in the transition between fused and unfused areas. Articular cartilage in unfused areas was thin, fibrillated, hypocellular and histochemically showed diminished proteoglycan content. Existing joint space was filled with fibrin and necrotic, acellular chondroid matrix. We conclude that MIA will produce fusion of the DIT and TMT joints of normal horses in 24 weeks, and may offer a relatively easy, inexpensive and non-invasive treatment for distal tarsal osteoarthritis in the horse.     

Radiographic evidence of degenerative joint disease in geriatric cats: 100 cases (1994-1997)

OBJECTIVE: To determine prevalence of radiographic evidence of degenerative joint disease (DJD) in geriatric cats. DESIGN: Retrospective study. POPULATION: 100 cats > 12 years of age. PROCEDURE: One investigator reviewed radiographs and for each articulation (or group of articulations) that was visible assigned a grade of severity (0, 1, 2, 3) for DJD. Another investigator reviewed medical records and recorded signalment, environment, previous disease, diseases evident at time of radiography, FeLV vaccination and infection status, feline immunodeficiency virus serologic status, serum creatinine concentration, serum globulin concentration, and any other important findings. Associations between DJD of grade 2 or 3 and variables recorded from the medical record were determined. RESULTS: Radiographic evidence of DJD was evident in 90% of cats. Neurologic disease was associated with lesions in the lumbosacral portion of the vertebral column. Severe lesions were found in 17% of the elbow joints, but an underlying cause was not determined. CONCLUSIONS AND CLINICAL RELEVANCE: Degenerative joint disease was detected radiographically in most geriatric cats and may be an overlooked cause of clinical disease. Clinicians should be alert to the possibility that DJD is associated with neurologic signs.     

Evaluation of clinical signs and causes of lower urinary tract disease in European cats

OBJECTIVES: To investigate the clinical signs and causes of lower urinary tract disease (LUTD) in 77 cats. METHODS: Cats diagnosed with LUTD over a two-year period were included in the study. RESULTS: The study population comprised 67 male and 10 female cats. Uroliths occurred in 17 of the 77 cats (22 per cent), urethral plugs in eight cats (10 per cent) and urinary tract infection in six cats (8 per cent). In 44 cats (57 per cent), no specific cause for the disease was found and they were classified as having idiopathic LUTD. In two of the 77 cats (3 per cent) no definitive diagnosis was established. Pain was less common in cats with uroliths and haematuria was more often seen in cats with urinary tract infection. At presentation, urethral obstruction was diagnosed in 45 of the 77 cats (58 per cent). CLINICAL SIGNIFICANCE: The causes of LUTD found in cats in this study are similar to those that have been previously documented, and idiopathic LUTD is the most frequent diagnosis. However, the rate of urethral obstruction, particularly in cats with idiopathic LUTD, was higher than in other reports. The cause of this difference is unknown.     

Prevalence and risk factors for feline Bordetella bronchiseptica infection.

A cross-sectional survey of a convenience-sample of 740 cats was undertaken to obtain an estimate of the prevalence of Bordetella bronchiseptica infection, and to identify risk factors that might predispose them to the infection. Data on individual cats and household variables, including disease status and animal contacts were obtained by questionnaire. B bronchiseptica was isolated from 82 (11 per cent) of the cats sampled. The prevalence of B bronchiseptica varied with the type of household sampled, being 19.5 per cent in rescue catteries, 9 per cent in breeding catteries, 13.5 per cent in research colonies, and 0 per cent in household pets. On the basis of a univariable analysis, 19 of 29 predictor variables were found to be significantly associated with the isolation of B bronchiseptica, including an association with cats in rescue catteries, and with cats from premises with larger numbers of animals. Separate analysis of the rescue cattery subpopulation showed a highly significant association on multivariable analysis with current respiratory disease, suggesting that different risk factors may operate in this type of environment. In the whole sample there was also strong association with cats from households containing a dog with recent respiratory tract disease. The clinical signs observed in the B bronchiseptica-positive cats included sneezing, ocular and nasal discharges and coughing, although only the association with sneezing was statistically significant. There was no significant association between the isolation of B bronchiseptica and the isolation of respiratory viruses, suggesting that in some circumstances B bronchiseptica may be able to cause disease independently.     

Radiographic appearance of cardiogenic pulmonary oedema in 23 cats

O bjective : To describe the radiographic appearance of pulmonary oedema in cats with cardiac failure.
M ethods : Thoracic radiographs of 23 cats presented to a first opinion practice with signs of cardiac failure were reviewed. All cats had tachypnoea and/or dyspnoea and enlarged left atrium on echocardiography.
R esults : Pulmonary oedema was characterised radiographically by an increased opacity associated with a range of patterns and variable distribution. All cats had evidence of a reticular or granular interstitial pattern. This occurred in combination with alveolar pattern in 19 (83 per cent) cats, including six with air bronchograms, with increased diameter of pulmonary vessels in 16 (71 per cent) cats and with bronchial pattern in 14 (61 per cent) cats. The distribution of pulmonary oedema was considered to be diffuse/non-uniform in 14 (61 per cent) cats, diffuse/uniform in four (17 per cent) cats, multi-focal in four (17 per cent) cats and focal in the remaining one (4 per cent). Nine (39 per cent) cats were considered to have a regional distribution of oedema, including five (22 per cent) with a ventral distribution, three (13 per cent) with a caudal distribution and one (4 per cent) cat with a hilar distribution. The distribution of pulmonary opacities was bilaterally symmetrical in five (22 per cent) cats.
C linical S ignificance : The variable appearance of feline pulmonary oedema is likely to complicate its radiographic diagnosis.     

Retrospective study of 46 cases of feline haemobartonellosis in Israel and their relationships with FeLV and FIV infections

Forty-six cats with clinical haemobartonellosis were studied; 75 per cent of the cats of known age were two-and-a-half years old or younger, 50 per cent were intact males and 19.5 per cent were castrated males. The predominant signs of the disease were tachypnoea, lethargy, depression, anorexia, infestation with fleas, pale mucous membranes, icterus, emaciation, dehydration, splenomegaly, anaemia, leucocytosis, increased activities of alanine aminotransferase and aspartate aminotransferase, and azotaemia. Thirty-eight per cent of the cats that were tested for feline leukaemia virus (FeLV) antigen were positive, and 22 per cent of those tested for feline immunodeficiency virus (FIV) antibodies were positive. The prevalence of both FeLV and FIV was much higher than in the general Israeli cat population. The cats infected with both Haemobartonella felis and FeLV had a significantly lower body temperature, were more anaemic and the mean cell volume of their erythrocytes was greater than in the cats with haemobartonellosis alone.     

The radiological features of osteosarcoma of the appendicular skeleton in dogs: a review of 74 cases

The clinical features, sites of origin and radiological changes associated with 75 osteosarcomas of the appendicular skeleton in 74 dogs are reviewed. Clinical data and the areas affected were broadly similar to those in previously reported series of cases, but the precise sites of origin were found to vary considerably from the generally accepted predeliction site, which is the metaphysis. A wide spectrum of radiological changes was recorded. Only 61.3 per cent of tumours could be classified as characteristic. A further 21.3 per cent showed features suggestive of, but not specific for, osteosarcoma and were therefore classified as equivocal. In the remaining 17.3 per cent the radiological signs, although indicative of neoplasia and usually of malignancy, were quite uncharacteristic. Among 63 cases in which both radiographic and post-mortem examination of the lungs was performed the incidence of pulmonary metastases was 13 per cent, with total correlation between their radiological and pathological detection. Of ten dogs which were treated surgically, one with a radiographically atypical lesion has survived for more than four years.     

Prevalence of thermophilic Campylobacter species in cats and dogs in two animal shelters in Ireland

Rectal swabs or faecal samples for the isolation of Campylobacter species were taken from 120 dogs and cats in an animal shelter in which only one kitten showed signs of gastrointestinal disease, and rectal swabs were taken from 46 dogs, 22 of which showed signs of gastrointestinal disease, in another shelter. At the first shelter, the swabs from 24 of 47 dogs (51.1 per cent) and 36 of 48 cats (75 per cent) yielded a Campylobacter species. The rate of isolation was significantly higher from dogs and cats less than six months old, and significantly higher from cats than from dogs (P< or =0.05). At the second shelter Campylobacter species were isolated from 40 of 46 dogs (87 per cent), but there was no significant difference between the age groups. Campylobacter species were isolated from 19 (86.4 per cent) of the 22 dogs with signs of gastrointestinal disease and from 21 (87.5 per cent) of the 24 unaffected dogs. Several culture methods were applied to the samples collected from both shelters, and the combination significantly increased the recovery of Campylobacter species.     

Canine dilated cardiomyopathy: a retrospective study of signalment, presentation and clinical findings in 369 cases

O bjective : To review the clinical and diagnostic findings and survival of dilated cardiomyopathy from a large population of dogs in England.
M ethods : A retrospective study of the case records of dogs with dilated cardiomyopathy collected between January 1993 and May 2006.
R esults : There were 369 dogs with dilated cardiomyopathy of which all were pure-bred dogs except for four. The most commonly affected breeds were dobermanns and boxers. Over 95 per cent of dogs weighed more than 15 kg and 73 per cent were male. The median duration of signs before referral was three weeks with 65 per cent presenting in stage 3 heart failure. The most common signs were breathlessness (67 per cent) and coughing (64 per cent). The majority of dogs (89 per cent) had an arrhythmia at presentation and 74 per cent of dogs had radiographic signs of pulmonary oedema or pleural effusion. The median survival time was 19 weeks.
C linical S ignificance : Dilated cardiomyopathy occurs primarily in medium to large breed pure-bred dogs, and males are more frequently affected than females. The duration of clinical signs before referral is often short and the survival times are poor. Greater awareness of affected breeds, clinical signs and diagnostic findings may help in early recognition of this disease which often has a short clinical phase.     

Meniscal Mineralization in Domestic Cats

Objective: To (1) determine prevalence of radiographically detectable meniscal mineralization in domestic cats and (2) to evaluate the association between meniscal mineralization and degenerative joint disease (DJD). Study Design: Prospective study. Animals: Client‐owned cats (n=100) and 30 feline cadavers. Methods: Randomly selected client‐owned cats were used to determine the prevalence of meniscal mineralization. Stifles from feline cadavers were used to evaluate the relationship between meniscal mineralization (using high‐resolution X‐ray), radiographic DJD, and cartilage damage. Menisci were evaluated histologically. Results: Forty‐six percent of the client‐owned cats had meniscal mineralization detected in 1 or both stifles. Pain scores were not significantly different between stifles with meniscal mineralization and those with no radiographic pathology (P=.38). Thirty‐four of 57 cadaver stifles had meniscal mineralization, which was always located in the cranial horn of the medial meniscus. Percentage mineralization of the menisci was significantly correlated with the cartilage damage score of the medial femoral (r²=0.6; P<.0001) and tibial (r²=0.5; P<.0001) condyles as well as with the total joint cartilage damage (r²=0.36; P<.0001) score and DJD score (r²=0.8; P<.0001). Conclusion: Meniscal mineralization is a common condition in domestic cats and seems to indicate medial compartment DJD. Clinical Relevance: Clinical significance of meniscal mineralization is uncertain. Further work is needed to determine if the meniscal mineralization is a cause, or a consequence of joint degeneration.     

Prevalence of feline leukaemia virus and antibodies to feline immunodeficiency virus and feline coronavirus in stray cats sent to an RSPCA hospital

A total of 517 stray cats at an RSPCA veterinary hospital were tested for feline leukaemia virus (FeLV), feline coronavirus (FCoV) and feline immunodeficiency virus (FIV). The prevalence of FeLV was 3.5 per cent in all the cats, 1.4 per cent in healthy cats and 6.9 per cent in sick cats. FeLV positivity was associated only with disease of non-traumatic origin. Antibodies to FCoV were present in 22.4 per cent of the cats, and their prevalence was significantly higher in cats over two years old and in feral/semiferal cats. The prevalence of antibodies to FIV was 10.4 per cent in all the cats, 4.9 per cent in healthy cats and 16.7 per cent in sick cats. The prevalence of FIV antibodies was significantly higher in entire males and neutered males than in females, in cats over two years old compared with younger cats, and in cats suffering disease of non-traumatic origin rather than in healthy cats or cats suffering only from trauma. Sex, age and health status were each independently highly associated with FIV antibodies.     

Prospective open pilot study on the use of ciclosporin for feline allergic skin disease

OBJECTIVES: To evaluate the efficacy of ciclosporin in cats with allergic skin disease. METHODS: Ten cats with signs of allergic skin disease were administered ciclosporin daily at a dose of 3.6 to 8.3 mg/kg for one month. None of these cats had previously responded to a hypoallergenic diet trial, and all animals had previously been treated with endectoparasiticidal drugs, with no improvement two weeks before entering the trial. On days 0 and 30, owners assessed pruritus with a visual analogue scale, and veterinarians evaluated cutaneous lesions. RESULTS: All the cats had pruritus and erythema, five had alopecia, two had an eosinophilic plaque, one had miliary dermatitis and two had both alopecia and an eosinophilic plaque. Good or excellent improvement was observed in 40 per cent of cats for pruritus, 57 per cent of cats for alopecia and 60 per cent of cats for erythema. A significant decrease in mean scores was observed for pruritus only, while for erythema and alopecia, it was close to being significant (P < 0.052). CLINICAL SIGNIFICANCE: Ciclosporin may be helpful in symptomatically treating signs of feline allergic skin disease. However, it is important to remember that ciclosporin is not licensed for use in cats.     

Endogenous lipid pneumonia in cats: 24 cases (1985-1998)

OBJECTIVE: To determine clinical signs, radiographic and histologic abnormalities, and concurrent diseases in cats with endogenous lipid pneumonia (EnLP) and to determine the pathologic importance of EnLP in cats. DESIGN: Retrospective study. ANIMALS: 24 cats. PROCEDURE: Medical records of cats in which EnLP was confirmed by histologic examination of necropsy specimens were reviewed. Information collected from the medical records included signalment, body weight, clinical signs, and results of clinicopathologic tests. Thoracic radiographs were reviewed by a radiologist; histologic specimens were reviewed by a pathologist. RESULTS: All cats had nonspecific clinical abnormalities, such as lethargy, anorexia, or weight loss; 16 had signs of respiratory tract disease. All cats had concurrent systemic diseases, and clinicopathologic abnormalities were reflective of these conditions. Nonspecific abnormalities were detected on thoracic radiographs from 9 of 11 cats. Most cats had macroscopic, multifocal, subpleural lesions; inflammatory infiltrates, cholesterol clefts, and multinucleated giant cells were common. Ten cats had an underlying obstructive pulmonary disease that was the likely cause of EnLP. Lesions of EnLP were not considered to be severe enough or extensive enough to be the cause of death in any of these cats. CONCLUSIONS AND CLINICAL RELEVANCE: EnLP is an uncommon respiratory tract disorder of cats with no pathognomonic clinical, laboratory, or radiographic findings. Although EnLP was not the cause of death in any of these cats, results of the present study do suggest that EnLP may be a marker for potentially severe underlying obstructive pulmonary disease.     

Prevalence of polycystic kidney disease in Persian cats in the United Kingdom.

The prevalence of polycystic kidney disease was assessed in 132 Persian cats, 46 of them referred for the investigation and treatment of medical or surgical conditions, and 86 apparently healthy cats referred specifically to be screened for the disease. Cats referred for the investigation of renomegaly or renal failure were excluded, and cats under 10 months old were only included if they had been examined postmortem. One hundred and twenty-six of the cats were examined ultrasonographically with a 7.5 MHz sector scanner, and the other six cats were examined postmortem. Forty-nine of the 86 cats referred specifically for screening (57.0 per cent) and 16 of the 46 cats referred for other clinical reasons (34.8 per cent) were affected by the disease, giving an overall prevalence of 49.2 per cent.