Mitral valve murmurs in cavaliers

Degenerative mitral valve disease is a highly prevalent inherited disease in the cavalier King Charles spaniel. A breed scheme exists in the UK to try to reduce the impact of this disease.

Swift et al¹ studied the effects of the scheme by analysing more than 16,000 examinations on more than 8,800 cavaliers, carried out at shows or in private practice between 1991 and 2010.

The examinations recorded the presence or absence of a murmur consistent with mitral regurgitation and the age the murmur was first noted.

Cardiologists detected murmurs at a younger age than general practitioners. The median age murmurs were detected was 7.8 years for males and 8.3 years for females. Significant increase occurred in the age of detection in bitches examined by GP vets over time, but this did not occur in male dogs or dogs examined by cardiologists.

The authors concluded application of the breeding guidelines may help increase the age mitral valve murmurs are detected, but compliance with this voluntary scheme is poor. It should be noted a mandatory scheme in Denmark produced a significant decrease in the prevalence of mitral valve disease over 8 to 10 years.

BP in rescue cats

It is often recommended the blood pressure (BP) of cats is assessed as part of health checks, since it can be elevated in various diseases, including hyperthyroidism and chronic kidney disease. However, stress can lead to large variations in BP in healthy cats.

Payne et al² measured BP in 780 cats being screened for cardiac disease in rescue centres. Cats with known systemic disease or hypertension were excluded. The median BP was 121mmHg, but increased with age, nervousness and history of being a stray. Older and male cats also had higher BPs.

The authors recommended temperament, age, sex and history of being a stray were taken into account when interpreting BPs.

Mycoplasma link to respiratory disease

Respiratory tract disease (RTD) in cats has a number of causes, including infectious and immune-mediated.

Le Boedec³ performed a systematic review and meta-analysis of 12 studies to assess the association between Mycoplasma species, and upper and lower RTD.

A significant association existed between upper RTD and the isolation of Mycoplasma, but not with lower RTD. However, the association with upper RTD was only significant in cases where conjunctival or pharyngeal swabs were tested using a Mycoplasma felis-specific PCR.

The author concluded evidence suggested M felis was a primary pathogen in feline upper RTD. Asymptomatic carriage, especially in cats in rescue centres, means interpretation should take the environment into account.

Rectal masses in dogs

Colonoscopy is a useful non-invasive technique for investigating lower gastrointestinal tract disease.

Adamovich-Rippe et al⁴ produced a retrospective case series of 82 dogs with rectal masses that had undergone colonoscopy. Six dogs had multiple rectal masses, but in these cases, no masses were found beyond the colorectal junction. In 64 cases that underwent surgical biopsy, 58 were histologically consistent with epithelial neoplasia; 71% were benign adenoma or polyp and 29% adenocarcinoma in situ or adenocarcinoma.

Minor complications occurred in three dogs, with no major complications. In 16 cases, colonoscopic and surgical biopsies had histology performed, and in 5 of these, a discrepancy existed in diagnosis between the two sampling techniques.

The authors concluded multiple rectal masses were uncommon in dogs and lesions beyond the colorectal junction were not present in this study, which may reduce the need for colonoscopy of the entire colon.

Chemotherapy in dogs with thrombocytopenia

Thrombocytopenia can occur as an immune-mediated disease or due to bone marrow disease in cancer patients.

Finlay et al⁵ performed an observational epidemiological cohort study to assess whether thrombocytopenia increased the risk of adverse effects in cases treated with standard chemotherapy.

In total, 77 patients with thrombocytopenia – platelet count lower than 200,000/ul – were assessed prospectively and compared with a retrospective cohort in which the platelet count was greater than 200,000/ul. No significant difference in gastrointestinal side effects or haemorrhage were noted between the thrombocytopenic and non-thrombocytopenic dogs.

The authors concluded no evidence existed of increased risk of haemorrhagic or gastrointestinal adverse effects in thrombocytopenic dogs receiving standard chemotherapy.

Hypothermia effects

Hypothermia can occur due to environmental conditions, disease, medications, trauma and anaesthesia, and can be applied therapeutically.

Brodeur et al⁶ reviewed knowledge regarding the effects, treatment and prognosis of hypothermia. Rewarming, the primary therapy, can be carried out with intensities ranging from passive surface warming to extracorporeal warming, with a goal of returning core temperature to a level where normal physiological functions are optimised. Other potential treatments include IV fluids and attention to underlying causes.

The authors noted few prognostic indicators existed, and even severely affected individuals presenting in cardiorespiratory arrest can make a full recovery. Although therapeutic hypothermia has improved outcome in human patients after cardiac arrest, further research is required to assess the prognosis for cases of hypothermia in veterinary medicine and whether therapeutic hypothermia is of value in veterinary patients.