Haemobartonellosis - contd.
Feline infectious anemia is caused by the organism Haemobartonella felis. This organism may be spread by fleabites, cat bites, blood transfusion, and by mothers to their kittens. Some cats infected with Haemobartonella have no symptoms, while others can develop life-threatening anemia. Cats that are also infected with feline leukemia virus are expected to have more severe signs of illness. Symptoms can include fever, depression, and loss of appetite. Signs of anemia may include lethargy, weakness, pale or jaundiced mucous membranes, and increased respiratory rate and effort. Severely affected cats may appear to be prostrate and depressed, or in shock. They can die suddenly with no apparent warning.
The anemia arises as infected red blood cells are attacked and destroyed by the immune system. The spleen is one of the major sites of red blood cell destruction. If the hemolytic process is severe, pigments from red blood cell breakdown may accumulate in the blood stream, resulting in jaundice.
Haemobartonella should be considered as a possibility in any anemic cat or any cat with evidence of hemolysis. The diagnosis is based on microscopic identification of H. felis on a blood smear. Since the appearance of H. felis on red blood cells is cyclical, the organisms may not be present all the time. In many cases, treatment is begun even if the diagnosis is only suspected and not confirmed.
Treatment of haemobartonellosis includes tetracycline antibiotics and prednisone. Blood transfusions may be required in patients with severe anemia. In cats that recover, a chronic carrier state develops. These chronic infections may persist for the life of the cat. Without treatment, as many as one out of every three cats with haemobartonellosis will die from the disease. Although they may be carriers of the organism, successfully treated cats have a good long-term outlook. Control of flea and tick infestations may help prevent re-infection with Haemobartonella.
