This will be a recurring series on Eye to the Future, where we will be looking into some of the more peculiar and odd eye conditions out there. Hopefully you will find these topics interesting, and if nothing else, maybe you can astonish your friends and family during Jeopardy!
Yes!!! Amazingly enough…
In addition to being a thinly veiled sexual euphemism made famous by rocker Ted Nugent, Cat Scratch Fever (or more accurately Cat Scratch Disease), is actually a relatively common condition that can cause some substantial eye related problems.
Cat Scratch Disease is a constellation of various systemic (and eye) symptoms that results from, logically, a cat’s scratch or bite. The underlying cause of Cat Scratch Fever is a bacterium called Bartonella (below, right) that was confirmed by Robert Debré in 1950 to be naturally occurring in cats and potentially infectious to humans. Bartonella is more commonly found in kittens/young cats and is most likely to occur in outdoor cats as fleas are the main method that Bartonella is spread within cat populations. Cats pick up this bug through fur cleaning of flea debris and foster this bacterium in their saliva which results in the spread to us through bites and scratches.
When Bartonella is transmitted to humans it has a latent period of 1-3 weeks from the initial bite, but it is not uncommon for symptoms to only pop up 1-2 months later when the memory of the cat scratch has long faded. Cat Scratch Fever commonly presents with tender, swollen lymph nodes near the site of the scratch/bite and the afflicted also suffer from severe flu like symptoms with malaise, aches, fever, headache, and joint/muscle pain. In very severe cases, Bartonella can also can meningitis (infection/inflammation in the brain) or endocarditis (infection/inflammation in the heart).
Pat
ients with undiagnosed Cat Scratch Fever will often make a trip to their local eye doctor during this time because Cat Scratch Fever can cause a severe conjunctivitis (pink eye) and even very blurry vision from optic neuritis or neuroretinitis (inflammation of the optic nerve and retina). The optic nerve carries the signal from to the eye to the brain and inflammation of this nerve results in decreased vision (left photo is normal, right has an inflammed optic nerve and retina). The blurry vision from Cat Scratch Fever neuroretinitis is usually temporary.
Now, take a breath…. I know you are likely glancing at your friendly, family feline with a mixture of repulsion and horror… Fear not! Cat Scratch Fever from Bartonella is usually very benign and all symptoms typically abate within a couple weeks without any treatment. In fact, Bartonella infection is estimated to be quite under-diagnosed simply because severe complications are rare and symptoms are similar to the flu, and like the flu, improve on their own. If severe complications from Cat Scratch Disease do present, it is possible to shorten the length of symptoms through oral antibiotics, but the medical literature is conflicted on which medicines work best and how much treatment actually improves the condition.
I hope you’ve enjoyed this quick talk and the next time you hear Nugent’s risqué anthem playing on the radio… let it be a reminder to think twice before petting stray cats!!
– Nick Wolf, OD