By Dr. Becker
Bartonellosis, also known as cat scratch disease or cat scratch fever, is an emerging global disease most commonly caused in cats by Bartonella henselae bacteria.
The infectious bacteria are carried in the saliva and feces of infected fleas and certain other external parasites. The fleas transmit the bacteria to cats in their feces. The flea feces remains on the cat’s skin, and gets ingested when the kitty grooms.
Cats who acquire bartonellosis can become carriers. Since the disease is zoonotic, meaning it can be transmitted from animals to humans and vice versa, cats are able to transmit Bartonella bacteria to people through scratches and bites.
Humans can’t acquire the infection from fleas, but both humans and cats can become infected by ticks. Fortunately, most cases of human bartonellosis are mild. The greatest risk is to people who are immunocompromised.
Symptoms of Feline Bartonellosis
Traditionally, it was thought that most cats with bartonellosis show no symptoms of illness, or have only mild, non-specific symptoms like fever, lethargy or lack of appetite.
More recently, however, several illnesses have been linked to Bartonella infection, including deep eye infections, enlarged lymph nodes, muscle pain, reproductive issues, and endocarditis, which is inflammation of the heart.
Kittens, older cats and those who are immunocompromised are most likely to become ill from Bartonella. When symptoms do develop, widespread inflammation is the most common. The infection typically affects a number of bodily systems, including the respiratory, digestive, neurological and cardiovascular systems, as well as the mouth, skin and lymph nodes. The mouth and lining of the GI tract may become swollen and inflamed, and there also may be shortness of breath and labored breathing.
Bartonella as a Cause of Plasma Cell Stomatitis
There is also evidence Bartonella infection may be a cause of plasma cell stomatitis, a progressive oral disease in cats. Kitties with both bartonellosis and FIV have an increased risk for plasma cell stomatitis. In addition, some cats with plasma cell stomatitis experience tremendous improvement when given antibiotics for treatment of Bartonella.
In my practice, this is the most common presentation. Many of my wonderful clients rescue or adopt all their pets. Young animals should have beautiful teeth because they haven’t lived long enough to acquire dental disease or stinky mouths, so when I see a rescued kitten or young cat with red, inflamed gums, not only do I check for FeLV and FIV, but I also suggest testing for Bartonella.
It is also suspected that Bartonella infection may be the root cause of a number of chronic inflammatory conditions in cats. So if you have a cat that just isn’t doing well or is plagued with chronic inflammation, consider asking your vet to check for Bartonella.
Diagnosing a Bartonella Infection
There are actually five different tests to diagnose bartonellosis – ELISA, IFA, PCR, culture and Western Blot.
The ELISA, IFA and Western Blot products test for antibodies against Bartonella, however, no titer guidelines have been established to confirm infection. In addition, around 10 percent of cats exposed to Bartonella do not make antibodies, which means they will test negative on these three tests.
The most accurate test is the blood culture, but several consecutive cultures are necessary because the bacteria circulates only intermittently. A positive culture confirms infection, but a negative culture may simply not have been taken at a time when the organism was circulating.
The PCR tests for the presence of Bartonella DNA, but since the bacteria circulates in the bloodstream only intermittently, the only advantage of this test over the blood culture is that the results come back a bit sooner.
So as you can see, it can be difficult to get a definitive diagnosis for this disease.
At the present time, the treatment of choice for feline bartonellosis is the antibiotic azithromycin, which clears over 80 percent of infected cats after about three weeks of treatment.
The outlook for cats with Bartonella infection depends a great deal on how the disease presents and which body parts it affects. I recommend supporting whichever organ systems need support during the course of the infection. In my practice, where we see a lot of kittens with inflamed, red gums secondary to a Bartonella infection, we encourage owners to address the oral inflammation naturally. We suggest adding ubiquinol and probiotics to the diet, as well as applying EFAC (esterified fatty acid complex) topically on the gums to help naturally reduce inflammation.
In the case of a Bartonella-positive cat with a deep eye infection, we would recommend lutein, zeaxanthin, astaxanthin, and vitamins E and C while treating the systemic infection.
As always, preventing an infection is preferable to treating it, so it’s important to keep your home and cat free of fleas and ticks, and regularly trim your kitty’s nails to prevent a Bartonella-positive cat from potentially passing the bacteria on to you or other family members.