Kerry Simpson

Feline diabetes mellitus in the UK: the prevalence within an insured cat population and a questionnaire-based putative risk factor analysis

Prevalence and risk factors for the development of diabetes mellitus (DM) in cats in the United Kingdom have not previously been reported. The prevalence of DM was evaluated in a large insured population and was found to be 1 in 230 cats. In this insured cat population Burmese cats were 3.7 times more likely to develop DM than non-pedigree cats. A convenience-sampling questionnaire-based study was used in order to identify putative risk factors for the development of DM. The univariate risk factor analysis identified being male, neutered, inactive, weighing ≥5 kg and having a history of corticosteroid treatment as significant risk factors for the development of DM in these cats. In addition, male cats treated with megestrol acetate had a significantly increased risk of developing DM compared to females. In contrast, there was no difference in DM occurrence between male and female Burmese cats. A multivariate classification tree-based model on the questionnaire data looking for interactions between risk factors, identified gender as the most important overall risk factor for the development of DM with low physical activity being the next most important risk factor for female cats and breed the next most important for male cats.

Prevalence of Tritrichomonas foetus infection in cats with diarrhoea in the UK

Faecal samples from 111 cats with diarrhoea that were living in the UK were submitted for the assessment of Tritrichomonas foetus infection by polymerase chain reaction (PCR). Sixteen (14.4%) samples were found to be positive. In agreement with studies from the USA, infected cats were predominantly of a year of age or less and of a pedigree breed, with Siamese and Bengal cats specifically over-represented in this population.

Cobalamin, folate and inorganic phosphate abnormalities in ill cats

Hypocobalaminaemia in cats has previously been identified, but the incidence reported has varied, and the frequency of folate deficiency is unknown. The aims of this study were to evaluate the incidence of low cobalamin and folate levels in a population of cats that were suffering predominantly from diseases of the alimentary tract (including the liver and pancreas) and to ascertain whether severity of disease (as assessed by bodyweight and body condition score (BCS)) related to degree of deficiency. The study population comprised 103 cats, of which 16.5% had low cobalamin levels and 38.8% had low folate levels. A serendipitous finding was inorganic phosphate levels below the reference range in 48% of the cases. Significant associations were found between subnormal cobalamin levels and median BCS (P=0.049); combined low folate and low cobalamin and bodyweight (P=0.002), BCS (P=0.024) and inorganic phosphate levels (P=0.003). The finding of low levels of folate and cobalamin in clinical cases suggests that supplementation may be indicated more frequently than is currently recognised.

Suspected toxoplasma—Associated myocarditis in a cat

Clinical toxoplasmosis is commonly reported in the cat, with the most consistent findings being ocular, pulmonic, hepatic, neurological, gastrointestinal and muscular abnormalities. Myocarditis, whilst frequently identified at post-mortem examination, has not been identified ante-mortem. In immunocompromised humans, myocarditis associated with toxoplasmosis is not an uncommon complication. In such cases, lymphocytic myocardial infiltration can lead to depressed myocardial function, which can be associated with congestive heart failure, rhythm disturbances and pericardial effusions. In addition, myocardial failure has been reported in immunocompetent humans associated with active toxoplasmosis [Chandenier J, Jarry G, Nassif D, Douadi Y, Paris L, Thulliez P, Bourges-Petit E, Raccurt C (2000) Congestive heart failure and myocarditis after seroconversion for toxoplasmosis in two immunocompetent patients. European Journal of Clinical Microbiological Infectious Disease 19, 375–379]. Here we describe a cat with echocardiographic changes consistent with infiltrative or inflammatory disease, and elevated IgG and IgM titres to Toxoplasma gondii. There was resolution of these myocardial changes once the toxoplasmosis was treated.

Pulsed-wave Doppler tissue imaging velocities in normal geriatric cats and geriatric cats with primary or systemic diseases linked to specific cardiomyopathies in humans, and the influence of age and heart rate upon these velocities.

Pulsed-wave Doppler tissue imaging (pw-DTI) techniques allow the non-invasive assessment of myocardial dynamics. pw-DTI has demonstrated regional and global diastolic impairment in various forms of human and feline cardiomyopathy. We hypothesise that in geriatric cats with systemic diseases that have been linked to specific cardiomyopathies in human beings, the myocardial velocity profile will be altered when compared to either normal or hypertrophic cardiomyopathy (HCM) cats; and that both age and heart rate have a significant affect upon pw-DTI velocities. The aims of this study were to determine whether the feline M-mode or myocardial velocity profile is altered in geriatric cats with disease states that have been linked to specific cardiomyopathies in humans when compared to normal geriatric cats or geriatric cats with HCM and to determine whether age or heart rate has a significant effect upon pw-DTI velocities within these groups of cats. Sixty-six cats aged 8 years or above were included in the study, and were divided as follows: Unaffected (n=8), basilar septal bulge (BSB) (17), HCM (14), hyperthyroid (HiT4) (12) and chronic renal failure (CRF) (15). Systolic blood pressure was normal in all the cats. pw-DTI systolic (S′), early (E′) and late diastolic (A′) velocities were assessed from standardised sites within the myocardium, and the relationships between these and disease group, age and heart rate were then assessed. In cats with HCM, the E′ velocity was decreased at various sites. Conversely, the HiT4 cats demonstrated increased S′ velocities. The only site at which the age of the cat was significantly related to myocardial velocities was the S′ velocity from the apical mid-septum. There were also significant positive relationships between heart rate and the magnitude of myocardial S′, E′ and A′ velocities of radial motion and S′ and A′ velocities of longitudinal motion. pw-DTI detected diastolic dysfunction in untreated cats with HCM and increased systolic function in HiT4 cats. The age of the cat was of little significance, whereas heart rate significantly influenced myocardial velocity profiles.

Colour M-mode tissue Doppler imaging in healthy cats and cats with hypertrophic cardiomyopathy

OBJECTIVES To determine whether decreased diastolic and systolic myocardial velocity gradient between the endocardium and the epicardium exist in the left ventricle of cats with hypertrophic cardiomyopathy. METHODS Myocardial velocity gradient and mean myocardial velocities were measured by colour M-mode tissue Doppler imaging in the left ventricular free wall of 20 normal cats and 17 cats with hypertrophic cardiomyopathy. RESULTS The peak myocardial velocity gradient (sec(-1)) during the first (E1) (5.71+/-1.75 versus 11.38+/-3.1, P<0.001) and second phase (E2) (3.09+/-1.53 versus 7.02+/-3.1, P=0.005) of early diastole and also the maximum early diastolic myocardial velocity gradient (Emax) (6.12+/-2.1 versus 10.76+/-3.2, P<0.001) were reduced in cats with hypertrophic cardiomyopathy compared with normal cats. Peak myocardial velocity gradient during early systole (Se) was lower in affected cats than in normal cats (6.26+/-2.08 versus 8.67+/-2.83, P=0.006). Affected cats had a lower peak mean myocardial velocities (mm/s) during the two isovolumic periods (IVRb and IVCb) compared with normal cats (2.97+/-6.76 versus 12.74+/-5.5 and 22.28+/-9.96 versus 38.65+/-10.1, P<0.001, respectively). CLINICAL SIGNIFICANCE This study shows that hypertrophic cardiomyopathy cats have decreased myocardial velocity gradient during both diastole and systole and also altered myocardial motion during the two isovolumic periods. Myocardial velocity gradients recorded by colour M-mode tissue Doppler imaging can discriminate between the healthy and diseased myocardium.

Pulmonary cowpox in cats: five cases

Case series summary This case series documents five cases of pneumonia (with pleural effusion in three cases) caused by cowpox virus (CPxV) in domestic cats. Predisposition to pneumonia may have resulted from mixed infections in two cases (feline herpesvirus and Bordetella bronchiseptica in one cat, and Mycoplasma species in the other). Relevance and novel information As well as diagnostic confirmation by previously described methods of virus isolation from skin lesions, and demonstration of pox virions in skin samples using electron microscopy and inclusion bodies in histological preparations, this is the first report of diagnosis by virus isolation from bronchoalveolar lavage fluid or pleural fluid, and demonstration of inclusion bodies in cytological preparations. This is also the first series to report treatment with interferon omega (IFN-ω). Two cats survived, both of which had been treated with IFN-ω. As CPxV represents a serious zoonotic risk it is an important differential diagnosis of pneumonia in cats.

Cloning and expression of feline colony stimulating factor receptor (CSF-1R) and analysis of the species specificity of stimulation by colony stimulating factor-1 (CSF-1) and interleukin-34 (IL-34)

Highlights ► Full-length feline CSF-1R has been cloned and expressed in a stable cell line. ► The biological activity of human, mouse and porcine CSF-1 has been evaluated. ► Human and mouse IL-34 are also biologically active on the feline CSF-1R. ► The potential therapeutic applications of CSF-1 is discussed.

Mycoplasma species in cats with lower airway disease: improved detection and species identification using a polymerase chain reaction assay

There is some evidence that Mycoplasma species may be associated with lower airway disease in cats. Retrospective and prospective studies were carried out on a total population of 76 cats but failed to identify any cases of Mycoplasma species infection by bacterial culture alone. The overall prevalence of bacterial infection (15.8%) was also lower than that identified in previous studies. When a molecular detection technique, the PCR-DGGE, was employed the prevalence of Mycoplasma species detected was 15.4%, with M felis, M gateae and M feliminutum species identified, although the significance of these Mycoplasma species in feline lower airway disease remains in question. However, the PCR-DGGE technique allowed species identification and indicated the presence of M feliminutum, a species not previously isolated from the lower airways of cats.

Comparison of digital and optical hand-held refractometers for the measurement of feline urine specific gravity

Measuring urine specific gravity (USG) is an important component of urine analysis as it evaluates renal concentrating capability. The objective of this study was to quantify the difference in USG values between a hand-held optical analogue refractometer and a cat-specific digital instrument. Urine samples from 55 cats were assessed. There was a statistically significant difference between these two refractometers (P<0.001), with the optical refractometer (mean USG=1.031) consistently reading higher than the digital refractometer (mean USG=1.027). Results for a random subset of the samples (n=10) were compared with urine osmolality and both the optical and digital instruments demonstrated excellent correlation. While an accurate USG reading is important, it is unlikely that the statistical significance between the two instruments is clinically significant and, therefore, unlikely to result in a change in patient evaluation or treatment plans. While both the digital and optimal refractometers are highly correlated to the urine osmolality, making both devices valid for assessment of USG in clinical practice, this digital device is easier to read and eliminates the variability of subjective interpretation.