Cardiac troponin I in healthy Norwegian Forest Cat, Birman and domestic shorthair cats, and in cats with hypertrophic cardiomyopathy.

OBJECTIVES: The aims of this study were to assess the potential associations between the serum cardiac troponin I (cTnI) concentration in healthy cats and feline characteristics, systolic blood pressure, heart rate (HR), echocardiographic measurements and storage time; and to compare cTnI concentrations in healthy cats with concentrations in cats with hypertrophic cardiomyopathy (HCM), with or without left atrial enlargement (LAE) and in cats with HCM, to assess potential associations between cTnI concentration and echocardiographic variables. METHODS: Cardiac TnI was analysed using an Abbott ARCHITECT ci16200 analyser in serum from prospectively included healthy Norwegian Forest Cat (NF; n = 33), Birman (n = 33) and domestic shorthair (DSH; n = 30) cats, and from 39 cats with HCM, with or without LAE. RESULTS: In healthy cats, higher cTnI concentrations were found in Birman cats than in NF cats (P = 0.014) and in neutered male cats than in intact females (P = 0.032). Cardiac TnI was positively associated with HR (P <0.0001). In cats with HCM, cTnI concentration was positively associated with left ventricular wall thickness and with left atrial-to-aortic root ratio (all P ⩽0.010). Cats with HCM had higher cTnI concentrations than healthy cats, and cTnI concentrations were higher in cats with HCM and LAE than in those with HCM without LAE (all P = 0.0003). CONCLUSIONS AND RELEVANCE: Breed and sex may affect serum cTnI concentrations in healthy cats. The cTnI concentration increased with increasing severity of HCM.

Concentrations of canine prostate specific esterase, CPSE, at baseline are associated with the relative size of the prostate at three-year follow-up.

BACKGROUND: Enlargement of the prostate is associated with prostatic diseases in dogs, and an estimation of prostatic size is a central part in the diagnostic workup. Ultrasonography is often the method of choice, but biomarkers constitute an alternative. Canine prostate specific esterase (CPSE) shares many characteristics with human prostate specific antigen (PSA) and is related to prostate size. In men with clinical symptoms of prostatic disease, PSA concentrations are related to prostate growth. The aims of the present follow-up study were to evaluate if the concentration of CPSE is associated with future growth of the prostate, and if analysis of a panel of 16 steroids gives further information on prostatic growth. Owners of dogs included in a previous study were 3 years later contacted for a follow-up study that included an interview and a clinical examination. The prostate was examined by ultrasonography. Serum concentrations of CPSE were measured, as was a panel of steroids. RESULTS: Of the 79 dogs included at baseline, owners of 77 dogs (97%) were reached for an interview, and 22 were available for a follow-up examination. Six of the 79 dogs had clinical signs of prostatic disease at baseline, and eight of the remaining 73 dogs (11%) developed clinical signs between baseline and follow-up, information was lacking for two dogs. Development of clinical signs was significantly more common in dogs with a relative prostate size of ≥2.5 at baseline (n = 20) than in dogs with smaller prostates (n = 51). Serum concentrations of CPSE at baseline were not associated with the change in prostatic size between baseline and follow-up. Serum concentrations of CPSE at baseline and at follow-up were positively associated with the relative prostatic size (Srel) at follow-up. Concentrations of corticosterone (P = 0.024), and the class corticosteroids (P = 0.0035) were positively associated with the difference in Srel between baseline and follow-up. CONCLUSIONS: The results support the use of CPSE for estimating present and future prostatic size in dogs ≥4 years, and the clinical usefulness of prostatic size for predicting development of clinical signs of prostatic disease in the dog. The association between corticosteroids and prostate growth warrants further investigation.

Influence of clinical setting and cat characteristics on indirectly measured blood pressure and pulse rate in healthy Birman, Norwegian Forest, and Domestic Shorthair cats.

BACKGROUND: Measured indirect blood pressure (BP) results in cats in a clinical environment might be affected by stress and characteristics of the cats. HYPOTHESIS: To investigate the influence of clinical setting, cat characteristics, and life situation on BP and pulse rate (PR) in healthy cats. ANIMALS: Ninety-four healthy Domestic Shorthair, Birman and Norwegian Forest cats. METHODS: Blood pressure measured by high-definition oscillometry in 3 settings: cat placed in its own carrier with veterinarian present; cat placed in carrier with owner alone present; and cat placed on table with veterinarian present. Statistical analyses were performed using mixed linear models. RESULTS: Systolic BP (SBP) did not differ among settings. Higher mean arterial pressure (MAP), diastolic BP (DBP), and PR were found when measurements were performed with cat placed on table, rather than in carrier. Coefficients of variation (CVs) higher for SBP, MAP, DBP, and PR when measured with cat placed on table than in carrier. Birman cats had lower BP than other breeds. Systolic BP, MAP, DBP, and PR increased with age. Cats allowed outdoors had lower PR than cats living strictly indoors. CONCLUSION AND CLINICAL IMPORTANCE: No difference in SBP was found among settings, but measuring BP with the cat placed on the examination table gave higher MAP, DBP, PR, and CV than measuring BP with the cat in its carrier. Breed affected BP, with lower BP in Birman cats than other breeds. Blood pressure increased with age. Pulse rate was lower in cats allowed outdoors than cats living strictly indoors.

Effect of feline characteristics on plasma N-terminal-prohormone B-type natriuretic peptide concentration and comparison of a point-of-care test and an ELISA test.

BACKGROUND: Increased plasma concentration of N-terminal-prohormone B-type natriuretic peptide (NT-proBNP) can be detected in cats with cardiac disease. Potential effects of feline characteristics on NT-proBNP concentration may influence clinical usefulness. OBJECTIVES: To evaluate potential effects of feline characteristics on NT-proBNP plasma concentration and to compare NT-proBNP plasma concentrations in healthy cats with results in hypertrophic cardiomyopathy (HCM) cats with or without left atrial enlargement (LAE) using an ELISA and a point-of-care test (POCT), and assess if POCT results reflect ELISA results. ANIMALS: One hundred healthy cats of 3 breeds and 39 HCM cats were included. METHODS: Diseases other than HCM were excluded by physical examination, blood pressure measurement, echocardiography, hematology, and serum biochemistry. RESULTS: Higher NT-proBNP concentrations were found in males than in females in healthy (P = .005) and in HCM cats (P = .0021), but breed had no effect on NT-proBNP concentrations. Using ≥100 pmol/L as a cutoff for abnormal samples, ELISA and POCT had similar sensitivity (SE; 72 and 74%) and specificity (SP; 97 and 98%) for detecting cats with HCM, cats with HCM and LAE (SE, both 100%; SP, 97 versus 98%), and cats with HCM without LAE (SE, both 69%; SP, 97 versus 98%), respectively, when compared to healthy cats. CONCLUSIONS AND CLINICAL IMPORTANCE: Breed had no effect on plasma NT-proBNP concentrations, but higher concentrations were found in male than in female cats. The ELISA and POCT had similar SE and SP for detecting HCM. Both tests could identify all HCM cats with LAE but not all HCM cats without LAE.

Interbreed variation of biomarkers of lipid and glucose metabolism in dogs.

BACKGROUND: Markers of lipid and glucose metabolism are used in both clinical practice and research. Detection of abnormal laboratory results often relies on species-specific reference intervals, but interbreed variation can also affect data interpretation. OBJECTIVES: The purpose of the present study was to compare concentrations of selected biochemical variables among different dog breeds. METHODS: We analyzed a database containing information on biochemical variables from 534 dogs belonging to nine different breeds. All dogs were confirmed to be healthy based on history, physical examination, and ancillary tests. Concentrations of glucose, fructosamine, insulin, cholesterol, triglycerides, fatty acids, and C-reactive protein were compared using the nonparametric Kruskal-Wallis and Dunn's tests. RESULTS: All variables tested showed significant interbreed differences, although all breeds remained within the previously established RIs for dogs. Fructosamine, insulin, and cholesterol showed a wide interbreed variation that could affect the interpretation of results. CONCLUSIONS: Breed is an important factor to consider when assessing energy metabolism in dogs, especially for markers like fructosamine, insulin, and cholesterol, which vary considerably among breeds.

Evaluation of an ELISA for metanephrines in feline urine.

Catecholamines can be used to evaluate neuroendocrine tumors, stress, and potentially pain, but catecholamines degrade rapidly. Their metabolites normetanephrine (NME) and metanephrine (ME) have better stability in urine. In cats, urine sampling in a home environment would be beneficial to reduce effects of clinical stress and simplify sampling. We evaluated a human urine ELISA for analysis of NME and ME in feline urine, and investigated the effects of acidification, cat tray pellets, and storage time at room temperature up to 8.5 h. In 26 feline urine samples, mean NME concentration was 192 ± 80 ng/mL, mean intra- and inter-assay CV was 6.5% and 4.2%, respectively, and spike recovery was 98-101%, but dilutional recovery was unsatisfactory. For ME, mean intra- and inter-assay CV was 10.2% and 4.1%, respectively. Mean urine ME concentration was 32.1 ± 18.3 ng/mL, close to the kit's lowest standard, and spike recovery was 65-90%; the ELISA could not be validated for ME. The stability study, performed for NME on 12 urine samples, did not identify differences between acidified and non-acidified samples, cat tray pellets, or storage time, and no interaction effects. The ME ELISA was not suitable for feline urine; performance of the NME ELISA was acceptable, except for dilution recovery. For analysis of NME, feline urine can be sampled at home using cat tray pellets and stored at room temperature up to 8.5 h without acidification.

Ambulatory electrocardiogram recordings in cats with primary asymptomatic hypertrophic cardiomyopathy.

Objectives The aims of the study were to determine the heart rate, rhythm, number of ventricular premature complexes (VPCs) and atrial premature complexes (APCs) in unsedated cats with asymptomatic hypertrophic cardiomyopathy (HCM), using 24 h ambulatory electrocardiogram (ECG) (Holter) in the home environment and to compare the results with those from healthy control cats. Methods Fifteen privately owned cats with asymptomatic HCM entered the study. Data from 23 healthy cats, previously published by our group, were used as the control. Clinical examination, measurement of blood pressure, echocardiographic examination, Holter recordings and biochemical analyses were performed in all cats. Holter recordings were obtained in the home environment. Results Three-lead ECGs of good quality were obtained from 15 cats with HCM. The median heart rate was 145 (interquartile range [IQR] 137-184) beats per minute for the cats with HCM. All cats with HCM presented with normal sinus rhythm; 60% of cats had intermittent sinus arrhythmia. Median number of VPCs was 3 (IQR 1-17). Three cats had APCs and three cats had both escape beats and intermittent sinus arrhythmia. Conclusions and relevance Asymptomatic cats with HCM had few VPCs and APCs on 24 h ambulatory ECG in the home environment. Intermittent sinus arrhythmia was observed in 60% of cats with HCM. The present study shows that the heart rate and the number of VPCs and APCs in cats with asymptomatic HCM are similar to that found in healthy control cats.

The Shepherds' Tale: A Genome-Wide Study across 9 Dog Breeds Implicates Two Loci in the Regulation of Fructosamine Serum Concentration in Belgian Shepherds.

Diabetes mellitus is a serious health problem in both dogs and humans. Certain dog breeds show high prevalence of the disease, whereas other breeds are at low risk. Fructosamine and glycated haemoglobin (HbA1c) are two major biomarkers of glycaemia, where serum concentrations reflect glucose turnover over the past few weeks to months. In this study, we searched for genetic factors influencing variation in serum fructosamine concentration in healthy dogs using data from nine dog breeds. Considering all breeds together, we did not find any genome-wide significant associations to fructosamine serum concentration. However, by performing breed-specific analyses we revealed an association on chromosome 3 (pcorrected ≈ 1:68 × 10-6) in Belgian shepherd dogs of the Malinois subtype. The associated region and its close neighbourhood harbours interesting candidate genes such as LETM1 and GAPDH that are important in glucose metabolism and have previously been implicated in the aetiology of diabetes mellitus. To further explore the genetics of this breed specificity, we screened the genome for reduced heterozygosity stretches private to the Belgian shepherd breed. This revealed a region with reduced heterozygosity that shows a statistically significant interaction (p = 0.025) with the association region on chromosome 3. This region also harbours some interesting candidate genes and regulatory regions but the exact mechanisms underlying the interaction are still unknown. Nevertheless, this finding provides a plausible explanation for breed-specific genetic effects for complex traits in dogs. Shepherd breeds are at low risk of developing diabetes mellitus. The findings in Belgian shepherds could be connected to a protective mechanism against the disease. Further insight into the regulation of glucose metabolism could improve diagnostic and therapeutic methods for diabetes mellitus.

The effect of a single dose of prednisolone in dogs envenomated by Vipera berus--a randomized, double-blind, placebo-controlled clinical trial.

BACKGROUND: Treatment with glucocorticoids after snakebite in dogs is controversial and randomized clinical studies are missing. The objective of this study was to investigate the effect of a single dose of prednisolone in dogs envenomated by Vipera berus in a double-blind placebo-controlled study, after exclusion of dogs treated with antivenom. The two treatment groups were compared regarding clinical status and clinicopathological test results. A total of 75 dogs bitten by Vipera berus within the previous 24 hours were included. Clinical assessment, blood sampling and measurement of the bitten body part were done at admission (Day 1), after 24 hours (Day 2) and at a re-examination (Re-exam) after 10-28 days. Dogs were given prednisolone 1 mg/kg bodyweight (PRED) or saline (PLACEBO) subcutaneously in a randomized, double-blind clinical trial. Dogs were examined clinically and mental status and extent of edema were described. Furthermore, appetite, vomiting, diarrhea, cardiac arrhythmia and death were recorded. Concentrations of C-reactive protein (CRP) and high sensitivity cardiac Troponin I (cTnI), hematology variables and Prothrombin time (PT) were determined. Systemic inflammation was defined as present if CRP > 35 mg/l. RESULTS: None of the dogs died during the study period. The mental status was reduced in 60/75 (80%) of dogs on Day 1, compared to 19/75 (25%) on Day 2. The proportion of dogs with no or only mild edema increased significantly from Day 1 to Day 2. About one-third of the dogs developed gastrointestinal signs during the study period. Cardiac arrhythmia was uncommon. Clinicopathological changes included increased total leucocyte count, CRP and troponin concentration on Day 2. The cTnI concentration was increased in dogs with systemic inflammation, compared to dogs without systemic inflammation. A single dose of prednisolone did not significantly affect any of the clinical or clinicopathological parameters studied, except for a higher monocyte count on Day 2 in dogs that had received prednisolone treatment. CONCLUSION: The results of the present study do not support routine administration of a single dose of prednisolone 1 mg/kg subcutaneously in dogs bitten by Vipera berus.

Evaluation of cytologic findings in feline conjunctivitis.

BACKGROUND: Cytologic examination of smears prepared from ocular swabs of conjunctiva from cats with conjunctivitis permits identification of the type of inflammation and possibly specific microorganisms. Results of studies of the diagnostic utility of cytology for detection of infectious causes of feline conjunctivitis have been inconsistent. OBJECTIVES: The objectives of this study were to describe cytologic findings in cats with conjunctivitis and to compare those findings with results of PCR analysis for feline herpesvirus (FHV-1), Chlamydophila felis (C felis), and Mycoplasma felis (M felis). METHODS: Conjunctival smears from 88 cats with conjunctivitis and 10 healthy control cats were stained with a Romanowsky stain and evaluated for the type of inflammation and evidence of an infectious agent. PCR analysis for FHV-1, C felis, and M felis was performed. RESULTS: Infectious agents identified by PCR analysis were FHV-1 in 9 cats (10%), C felis in 8 cats (9%), and M felis in 6 cats (7%). Inclusions interpreted as chlamydial inclusions were found in all cytologic smears from cats positive for C felis by PCR analysis and in 3 PCR-negative cats. Inclusions interpreted as Mycoplasma organisms were found in 3 of 6 cats that were PCR-positive for M felis and in 1 PCR-negative cat. FHV-1 inclusion bodies were not detected on cytologic examination. CONCLUSIONS: Cytologic examination can be diagnostic for C felis infection when many typical inclusions are present. Cytologic examination was unreliable in diagnosing M felis infection, and viral inclusions of FHV-1 were not found in specimens stained with Romanowsky stains.

An investigation on the presence of Chlamydiaceae in Swedish dogs.

BACKGROUND: Bacteria belonging to the family Chlamydiaceae cause a broad spectrum of diseases in a wide range of hosts, including man, other mammals, and birds. Upper respiratory and genital diseases are common clinical problems caused by Chlamydiaceae. Very little is known about chlamydial infections in dogs. Few clinical reports on natural disease in dogs describe mainly conjunctival and upper respiratory signs, and the role of Chlamydiaceae in genital disease is unclear. The present study aimed at studying the prevalence of Chlamydiaceae in healthy dogs and in dogs with genital or upper respiratory disease, including conjunctivitis. METHODS: A real-time polymerase chain reaction (PCR) for Chlamydiaceae was used to detect any chlamydial species within this family. Swab samples from the conjunctiva and the mucosal membranes of the oropharynx, rectum and genital tract were taken from 79 dogs: 27 clinically healthy dogs, 25 dogs with clinical signs from the genital tract and 28 dogs with conjunctivitis. There were 52 female and 27 male dogs. From 7 of the male dogs, additional semen samples were analysed. RESULTS: No Chlamydiaceae were detected from any dog. CONCLUSIONS: Although the number of dogs that was included is limited, the results suggest that cases of Chlamydiaceae in dogs probably are related to infection from other species, and that dogs in general do not harbour Chlamydiaceae. Bacteria belonging to the family Chlamydiaceae do not seem to be of major importance for genital or ocular disease in Swedish dogs.

Infectious causes for feline upper respiratory tract disease--a case-control study.

The aim of this case-control study was to investigate the prevalence of microorganisms in group-living cats with clinical signs of upper respiratory tract disease (URTD), in in-contact cats and in cats in groups without URTD problems. Samples were taken from the ventral conjunctival fornix for analysis of feline herpesvirus-1 (FHV), Mycoplasma felis and Chlamydiaceae using a real-time polymerase chain reaction technique. The oropharynx was sampled for bacteriological culture and viral isolation. Specific infectious agents were identified in 11/20 (55%) of the case households, in 7/20 (35%) of the cats with clinical signs and in 3/20 (15%) of the control households, in 3/40 (7.5%) of the cats. Chlamydiae and M felis were only detected from case households, both from cats with URTD and from in-contact cats. The difference in prevalence between case and control households was statistically significant for M felis (P=0.047). The presence of M felis in cat groups was thus associated with clinical signs of URTD.

Twenty-four hour Holter monitoring of unsedated healthy cats in the home environment.

OBJECTIVE: To determine the heart rate, rhythm, number of ventricular premature complexes (VPCs) and atrial premature complexes (APCs) in unsedated cats using Holter monitoring. ANIMALS, MATERIALS AND METHODS: Twenty-three healthy client owned cats were used. Clinical examination, blood pressure measurements, echocardiographic examination and serum biochemical analysis were performed. A lightweight Holter was used in the home environment. RESULTS: Three-lead electrocardiographic registrations of good quality were obtained from all cats. Normal sinus rhythm was present in all cats. The median heart rate was 165 beats per minute (bpm), range 70-303 bpm. Mean heart rate varied significantly with age and gender. Sinus arrhythmia occurred intermittently in 18 cats (78%). Uncommon ventricular premature complexes occurred in 18 (78%) of the cats. The median number of VPCs per cat was 3 complexes/24 h period, range 0-146. Cats 7-15 years of age had significantly more VPCs than cats 1-6 years of age (median 6 versus 1 per 24 h period, p=0.04). A single APC occurred in one cat (4%). CONCLUSIONS: Cats commonly have intermittent sinus arrhythmia. Many healthy cats have rare single VPCs per 24 h period. Old cats have significantly more VPCs than young cats. The heart rate varies significantly with age and gender.