When they examined him, they noticed his lymph nodes were swollen under his left armpit. Blood tests showed elevated levels of a marker of inflammation called C-reactive protein, abdominal ultrasound showed an enlarged spleen, and a PET-CT scan showed enlarged lymph nodes in his abdomen, too. That made the doctors fear he had late-stage lymphoma, a cancer of your white blood cells that can cause night sweats, unintentional weight loss, and swollen lymph nodes.
But bone marrow aspiration and biopsy came back normal—ruling out cancer—and blood tests for diseases like hepatitis, syphilis, and HIV came back negative, too.
Then, doctors tested the bone marrow and lymph nodes from biopsy for Bartonella henselae, a type of bacteria that cats can harbor. When the doctors asked him about it, the man told them he did have a cat at home—and he had been scratched recently.
The diagnosis? Invasive cat scratch disease. Doctors treated him with an antibiotic called tetracycline twice a day for three weeks. His symptoms disappeared, and he fully recovered his erectile function.
Cats often become infected with Bartonella henselae through flea bites, and most can carry the bacteria without getting sick from it. But they can transfer the bacteria to humans when they scratch you. Some people don’t get sick at all, but if you do, you’ll generally just experience a low-grade fever and enlarged lymph nodes, the Centers for Disease Control and Prevention (CDC) says.
So how could cat scratch disease affect your penis? It’s actually a very “atypical” presentation of the disease, the doctors write.
In rare cases, the bacteria can cause central nervous system disorders, including ones that can damage your brain. It can also cause nerve damage, the doctors write. If this affects your pudendal nerve—which carries signals to and from your genitals—that can make it hard to get an erection. It can also cause the penis pain the man experienced, too.
So this was a very rare presentation of cat scratch disease—that’s why it was chosen for publication as a case report. Plus, most scratches from cats don’t result in cat scratch disease at all, the CDC says. So no need to worry about your furry friend.
There’s not even any particular action the CDC recommends after a cat scratch besides cleaning with soap and water. If you develop symptoms—like a fever, swollen lymph nodes, or a pustule at the site of the scratch—you can see your doctor. Treatment with antibiotics usually aren’t necessary, unless you have more serious symptoms.
As for prevention, keep your cat free of fleas with spot treatments using fipronil like Frontline, and avoid playing rough with your pet, which can encourage him to scratch.
This article was originally published by Men's Health.