The discovery could mean that veterinary teams will be able to identify which dogs are at risk of side effects when treated for immune-mediated haemolytic anaemia (IMHA).

 

IMHA causes a dog’s immune system to mistakenly identify its red blood cells as a threat and destroy them. Symptoms include severe weakness, pale or yellow gums, and fast breathing.

 

The condition is associated with mortality rates of up to 35 to 70 per cent.

 

Its treatment will typically seek to suppress this immune response and restore the dog’s red blood cells. However the medications used, which include glucocorticoids, can cause significant side effects such as increased thirst and urination.

 

In some cases, these effects lead to the decision to euthanise a pet even when the disease is under control.

 

An RVC-led study has now revealed that the early rises in alkaline phosphatase (ALP) activity were associated with excessive drinking two to three weeks later. Researchers also found that many laboratory and clinical measurements changed substantially as treatment progressed.

 

The discovery was made after researchers analysed data from 29 dogs at the RVC’s Queen Mother Hospital, where they were in the initial stages of their treatment.

 

Researchers used blood samples which had already been collected as part of the dogs’ routine clinical care. They then monitored changes in test results, clinical measures and the activity of genes linked to the immune system and steroid treatment.

 

The findings are expected to be particularly important for dogs which are undergoing longer-term glucocorticoid treatment, with side effects having a significant impact on quality of life.

 

Dr Barbara Glanemann, associate professor in Small Animal Internal Medicine at the RVC, led the study. She said: “Our findings suggest commonly available laboratory changes early in treatment may help us all to better understand how an individual patient is responding and how high their risk is for developing adverse effects. This can help us to individualise our treatment strategies.”

 

Scientists recognise IMHA as the most common immune-mediated disease in dogs. Any breed can be affected, with cocker spaniels, springer spaniels and Irish setters among those at higher risk.

 

The full study can be found in the journal PLOS One.