IMHA in dogs

IMHA in dogs stands for **Immune-Mediated Hemolytic Anemia**. It is a serious, immune
system disorder where the dog’s immune system mistakenly attacks and destroys its own red
blood cells.

What is IMHA?
– An autoimmune disease in which antibodies target the dog’s own red blood cells (RBCs),
leading to their destruction (hemolysis).
– Results in anemia (low RBC count), which can be severe and life-threatening.

Types of IMHA
– Primary (Idiopathic): No identifiable cause; the immune system attacks RBCs without an
apparent trigger.
– Secondary: Caused by underlying factors such as infections, certain drugs, neoplasia, or
vaccinations that stimulate an immune response.

Signs and Symptoms
– Pale or jaundiced (yellowish) gums and mucous membranes
– Weakness, lethargy, or collapse
– Rapid breathing or respiratory distress
– Dark-colored urine (hemoglobinuria) due to hemolysis
– Fever or signs of infection (sometimes)
– Fever and enlarged spleen or lymph nodes (in some cases)

Diagnosis
– Blood smear:Presence of spherocytes (small, spherical RBCs) and auto-agglutination
– Blood tests:
– Anemia confirmed by low PCV/hematocrit
– Coombs’ test (direct antiglobulin test): detects antibodies attached to RBCs
– Elevated bilirubin (jaundice) if hemolysis is significant
– Reticulocyte count (to assess bone marrow response)
– Exclusion of other causes of anemia (e.g., parasites, toxins)

Treatment
– Immunosuppressive therapy:

– Corticosteroids (e.g., prednisone) are first-line
– Additional immunosuppressants (e.g., cyclosporine, azathioprine) may be added
– Supportive care:
– Blood transfusions if severe anemia
– Fluids to maintain hydration
– Preventing secondary infections
– Managing hemoglobinuria and supporting organ function

Prognosis
– Variable; many dogs respond well to treatment, especially if diagnosed early.
– Recurrence or chronic remission is common.
– Long-term immunosuppression may be necessary.

Summary
IMHA is a life-threatening autoimmune disease in dogs that requires prompt diagnosis and
aggressive treatment. Early intervention can significantly improve outcomes and quality of life.