Patient education: Cat scratch disease (The Basics)

What is cat scratch disease? — Cat scratch disease is an infection caused by a type of bacteria that is found in many cats. These bacteria don't make the cat sick. But you can get the disease if you are scratched or bitten by an infected cat or flea. You can also get it if an infected cat licks your eyes, mouth, or an open wound on your skin. Young cats are more likely than older cats to infect you.

The infection can cause redness, swelling, and small round bumps near the bite or scratch (picture 1). It also causes swollen "lymph nodes." Lymph nodes are bean-shaped organs found all over the body (figure 1). They make and store cells that fight infections.

What are the symptoms of cat scratch disease? — The symptoms include:

●Skin swelling or redness that happens 3 to 10 days after being infected – This can look like a bump or pimple.

●Swollen lymph nodes, especially around the head, neck, and arms

Other possible symptoms include:

●Fever

●Headache

●Feeling very tired

●Not feeling hungry

In rare cases, cat scratch disease can cause more serious problems, including:

●Confusion

●Vision problems

●Liver disease

Will I need tests? — Maybe. If you have symptoms of cat scratch disease, your doctor might order a blood test to see if you have it.

In some cases, a doctor might do a lymph node biopsy. They will remove the node or a small sample of tissue from the node. Then another doctor will look at the sample under a microscope. Rarely, other fluids or tissues might be tested as well.

How is cat scratch disease treated? — Although symptoms of cat scratch disease might go away in a few weeks without treatment, doctors often prescribe antibiotics to treat the infection.

Can cat scratch disease be prevented? — You can lower your chances of getting cat scratch disease if you:

●Avoid playing with or handling cats in ways that might lead to a bite or scratch

●Wash your hands after playing with cats

●Treat cats for fleas, if needed

●Wash cat bites or scratches right away with running water and soap

If you have a medical condition that it makes it hard for you to fight infection, such as HIV, you should avoid cats younger than 1 year old.

More on this topic

Patient education: Swollen neck nodes in children (The Basics)
Patient education: Animal and human bites (The Basics)

Patient education: Animal and human bites (Beyond the Basics)