CAUSES AND DEVELOPMENT

This dysfunction of the immune system can develop for no apparent reason (primary or idiopathic IMHA) or can be caused by an element (secondary IMHA). In theory, any infection, inflammation or tumor can trigger a dysfunction of the immune system. However, it is sometimes difficult to prove that there is a causal link between the two issues.

The Cocker Spaniel is predisposed to primary IMHA.

CLINICAL SYMPTOMS

The symptoms are secondary to the presence of anemia. Pale mucous membranes, weakness, intolerance to exercise and rapid breathing are often observed. In some cases, the mucous membranes become yellowish (jaundice) and/or the urine takes on a red-brown color if the liver is in pain.

Depending on the speed and severity of red blood cell destruction, the animal may require urgent care to be stabilized with a red blood cell transfusion.

DIAGNOSIS

The first step is to determine the cause of the anemia. Certain blood tests (auto-agglutination on a slide, Coomb’s test, presence of spherocytes in blood smear) make it possible to demonstrate the involvement of the immune system in the destruction of red blood cells.

The next step is to determine whether the IMHA is primary or secondary. Various additional examinations can therefore be considered to look for an underlying cause: complete blood test, ultrasound of the abdomen, chest x-rays, specific search for infectious agents, etc.

In some cases, the immune system attacks the blood cell precursors (young red blood cells that have not yet matured) found in the bone marrow before they have had time to be released into the blood circulation. In this case, a bone marrow analysis is recommended. This form of IMHA is more common in cats.

TREATMENTS AND PROGNOSIS

Treatment depends on the underlying cause. If no cause could be identified, immunomodulatory treatment (drugs that modulate the immune system) is implemented. If an underlying cause is identified or suspected, it is treated and the response to treatment is assessed by monitoring the red blood cell count.

In dogs, primary IMHA is more frequently diagnosed than secondary IMHA. Immunomodulatory treatment (corticosteroids) is therefore often necessary.

In certain cases, immunomodulatory treatment can be gradually reduced and stopped after several months; however, relapses may occur. Other cases require lifelong treatment.

Support with Hepa Supp™ and Anti-Ox™ is very helpful.

Dr Emilie Vangrinsven
Diplomate from European college of veterinary internal medicine | PhD U-Liège
Assistant at the Liege University in the university clinic for PETs | Author and co-author of numerous scientific publications