M. E. Herrtage

Study of 253 dogs in the United Kingdom with diabetes mellitus

Clinical information and blood samples were collected from 253 dogs with naturally occurring diabetes mellitus. Over half of them were labrador retrievers, collies, Yorkshire terriers or crossbred dogs, and approximately 80 per cent of them were diagnosed between the ages of five and 12 years. The majority of the dogs were receiving insulin therapy once a day, but in the dogs receiving insulin injections twice a day there was a trend for lower serum fructosamine concentrations, suggesting better glycaemic control. The proportion of female dogs with diabetes was lower than in previous surveys. The disease was diagnosed more commonly in the winter months, a seasonal pattern also observed in human beings with diabetes, suggesting that similar environmental factors might be involved in the disease.

Identification and distribution of a novel Malassezia species yeast on normal equine skin

This study aimed to investigate the distribution of Malassezia species yeasts on the skin of healthy horses. Acetate tape samples were obtained from the lip, axilla, interbulbar region, groin and anus of 12 healthy horses. The samples were stained and examined microscopically and sites harbouring yeast-like organisms were identified. Contact plates were applied to the skin at these sites and cultured at 26°C and 32°C. No growth was obtained on horse blood, Sabourauds dextrose or modified Dixons agar. A pure growth of a Malassezia-type organism was obtained on Sabourauds dextrose agar enriched with oleic acid when it was incubated at 30°C. It was identified by 26S ribosomal DNA D1/D2 sequence analysis as a member of the genus Malassezia, and most closely related to Malassezia sympodialis. However, the level of sequence divergence indicated that it was a novel species.

Role of chronic disseminated intravascular coagulation in a case of canine angiostrongylosis

A dog whose major clinical signs suggested a coagulopathy, is described. The dog had a history of bleeding episodes and had a severe regenerative anaemia. By using specific factor assays, the coagulopathy was found to be due to a consumptive intravascular process that resembled chronic disseminated intravascular coagulation. Subsequent investigations identified Angiostrongylus vasorum as the cause.

Observational study of 14 cases of chronic pancreatitis in dogs

This study reports the clinical, clinicopathological and ultrasonographic findings from dogs with chronic pancreatitis (CP). Fourteen dogs with clinical signs consistent with CP and histological confirmation of the disease were evaluated. Abdominal ultrasound and clinical pathology results were recorded. Sensitivities of pancreatic enzymes for diagnosis of CP were calculated with two different cut-off values. The mean age of affected dogs was 9.1 years. Spaniels were the most common breed with CP, representing seven of the 14 dogs in this study. CP was histologically severe in nine cases. Most dogs showed chronic low-grade gastrointestinal signs and abdominal pain. Five dogs had exocrine pancreatic insufficiency and five dogs had diabetes mellitus. The sensitivity of elevated trypsin-like immunoreactivity for CP was 17 per cent. The sensitivities of canine pancreatic lipase immunoreactivity, lipase and amylase for CP were 44 to 67 per cent or 14 to 28 per cent depending on the cut-off value used. Cholesterol was elevated in 58 per cent of samples. Liver enzymes were often elevated. The pancreas appeared abnormal on 56 per cent of ultrasound examinations. Ten dogs had died by the end of the study period; only one case was due to CP.

Long-term outcome of 56 dogs with nasal tumours treated with four doses of radiation at intervals of seven days.

A retrospective study was undertaken on 56 dogs treated for nasal tumours by megavoltage radiotherapy with a hypofractionated schedule consisting of four doses of 9 Gy given at intervals of seven days. The dogs were followed until they died or were euthanased. The clinical signs had improved in 53 of the 56 dogs by the end of the treatment schedule. Mild acute radiation side effects were observed in the majority of the dogs but late radiation side effects were rare. Kaplan-Meier survival analysis revealed a median survival time after the final dose of radiation of 212 days. The oneand two-year survival rates were 45 per cent and 15 per cent. Fifty of the dogs were euthanased because the initial clinical signs recurred.

Glomerular filtration rate estimated by 3-sample plasma clearance of iohexol in 118 healthy dogs.

BACKGROUND Glomerular filtration rate (GFR) decreases in the aging human kidney, but limited data exist in dogs. HYPOTHESIS There is an effect of age and body size on estimated GFR in healthy dogs. ANIMALS One hundred and eighteen healthy dogs of various breeds, ages, and body weights presenting to 3 referral centers. METHODS GFR was estimated in clinically healthy dogs between 1 and 14 years of age. GFR was estimated from the plasma clearance of iohexol, by a compartmental model and an empirical correction formula, normalized to body weight in kilograms or liters of extracellular fluid volume (ECFV). For data analysis, dogs were divided into body weight quartiles 1.8-12.4, 13.2-25.5, 25.7-31.6, and 32.0-70.3 kg. RESULTS In the complete data set, there was no trend toward lower estimated GFR/kg or GFR/ECFV with increasing age. GFR decreased with age in dogs in the smallest weight quartile only. A significant negative linear relationship was detected between body weight and estimated GFR/kg and GFR/ECFV. Reference ranges in different weight quartiles were 1.54-4.25, 1.29-3.50, 0.95-3.36, and 1.12-3.39 mL/min/kg, respectively. Standardization to ECFV rather than kilogram body weight did not produce substantial changes in the relationships between GFR estimates and age or weight. CONCLUSIONS AND CLINICAL IMPORTANCE Interpretation of GFR results for early diagnosis of renal failure should take into account the weight and the age of the patient for small dogs.

Survey of mistakes made by recent veterinary graduates

To investigate the incidence and types of mistakes made in veterinary practice, and to assess the impact the mistakes had on the veterinarians involved, a questionnaire was sent in November 2002 to all the veterinary graduates of the Universities of Bristol, Edinburgh, Glasgow, London and Liverpool in 2001. One hundred and eight (27 per cent) of 402 questionnaires were returned completed; 87 of 106 respondents (82 per cent) worked frequently or always unsupervised and only 46 (43 per cent) could always rely on support from other veterinarians in the practice. Since starting work, 82 of 105 respondents (78 per cent) stated that they had made a mistake, defined as an erroneous act or omission resulting in a less than optimal or potentially adverse outcome for a patient, and in many cases these mistakes had had a considerable emotional impact on the veterinarians involved. The survey highlights that a large number of recently graduated veterinarians work with little supervision and that many veterinarians beginning their year in practice do not always have access to assistance from other veterinary colleagues.

The Cardiac Biomarker NT-proBNP Is Increased in Dogs with Azotemia

BACKGROUND Amino-terminal probrain natriuretic peptide (NT-proBNP) has been proposed as a useful biomarker for heart disease in dogs. In humans, decreased glomerular filtration rate (GFR) increases NT-proBNP. OBJECTIVE To investigate whether decreased GFR as indicated by plasma creatinine concentration is associated with increased NT-proBNP in dogs without heart disease. ANIMALS Four groups of dogs: healthy (n= 39), azotemic (n= 36), heart disease (n= 37), and congestive heart failure (CHF) (n= 7) presented to 2 teaching hospitals. METHODS Prospective observational cohort study. Plasma creatinine concentration and NT-proBNP were measured in every dog. Nonparametric tests were used to compare the differences among groups. The median and actual results for each group were compared with the manufacturers recommended and previously published suggestions for cut-off values for diagnosis of heart disease. RESULTS Median (range) plasma creatinine concentration was 1.47 (1.06-1.70), 4.36 (1.74-15.6), 1.22 (0.69-1.91), and 1.45 (0.63-1.64) mg/dL and median (range) NT-proBNP was 118 (2-673), 556 (37-1,819), 929 (212-5,658), and 3,144 (432-5,500) pmol/L for the healthy, azotemic, heart disease, and CHF groups, respectively. Pair-wise comparison indicated a significant difference among all groups for NT-proBNP (P< or = .049). Plasma creatinine concentration was significantly higher in the azotemic group compared with other groups (P < .001) but there was no significant among other groups. Application of 3 recommended cut-off values led to misclassification of dogs with azotemia as having heart disease. CONCLUSIONS Azotemia results in NT-proBNP being increased to concentrations reported as diagnostic of heart disease or heart failure in dogs. Care should be employed when interpreting the results of NT-proBNP in patients with known or possible increased plasma creatinine concentration.

Hypovitaminosis D in dogs with inflammatory bowel disease and hypoalbuminaemia.

OBJECTIVES To compare serum vitamin D metabolites and plasma parathyroid hormone concentrations in dogs with inflammatory bowel disease and normal albumin concentration, dogs with inflammatory bowel disease and hypoalbuminaemia, healthy dogs and hospitalised ill dogs with non-gastrointestinal illness. METHODS Serum 25 hydroxyvitamin D and 1,25 dihydroxyvitamin D concentrations were measured in 36 healthy dogs, 49 hospitalised ill dogs with non-gastrointestinal illnesses, 21 dogs with inflammatory bowel disease and normoalbuminaemia and 12 dogs with inflammatory bowel disease and hypoalbuminaemia. Plasma parathyroid hormone and ionised calcium concentrations were measured in a subset of these dogs. RESULTS Concentrations of serum 25 hydroxyvitamin D were lower in hypoalbuminaemic dogs with inflammatory bowel disease than in the healthy dogs (P<0·001), hospitalised ill dogs (P<0·001) and normoalbuminaemic dogs with inflammatory bowel disease (P<0·001). Dogs with inflammatory bowel disease and hypoalbuminaemia had a higher plasma concentration of parathyroid hormone (P<0·01) and lower plasma concentration of ionised calcium (P<0·001) than hospitalised ill dogs. Dogs with inflammatory bowel disease had a positive correlation between serum 25 hydroxyvitamin D concentrations and serum albumin (P<0·0001), serum calcium (P<0·0001) and plasma ionised calcium (P<0·0005) concentrations. CLINICAL SIGNIFICANCE Dogs with inflammatory bowel disease and hypoalbuminaemia frequently have ionised hypocalcaemia, high parathyroid hormone and low serum 25 hydroxyvitamin D concentrations. Further studies are indicated to establish the pathogenesis of this disease complication as well as therapeutic strategies to reverse this state.

Prevalence of hepatic lesions at post-mortem examination in dogs and association with pancreatitis.

OBJECTIVES To assess the prevalence of canine chronic hepatitis (CH) and other liver diseases in first opinion practice and identify associations with concurrent chronic pancreatitis (CP). METHODS One large section of left lateral lobe of liver was taken from 200 unselected canine post-mortem examinations from first opinion practices. Histological changes were categorised based on WSAVA criteria. Prevalence of CH and other liver diseases were calculated. Relative risks (RR) for liver histopathology in association with CP and for CH in different breeds were also calculated. RESULTS The prevalence of CH was 12%. Some breeds had an increased RR of CH, although sample sizes were small. Dogs with CP had an increased RR of reactive hepatitis but no significant association with the other liver diseases. CLINICAL SIGNIFICANCE CH is common in the first opinion dog population but less common than CP. CP was significantly associated with reactive hepatitis but not CH. Possible breed associations mirrored another recent UK study. Some dogs with CP may be erroneously diagnosed clinically as having CH on the basis of increased serum liver enzymes because of concurrent reactive hepatitis if the diagnosis is not confirmed histologically.