DRHOOK- Feline poorly? Toxoplasmosis nothing to meow about

the handsome doctor John Hong

Britney Spears is back! She was pretty good in Glee (yes, I'm a Gleek. Laaaa!), and she hasn't shaved her head in years. But as much as I love Glee, I didn't appreciate their version of Britney's top song, "Toxic." They turned this innovative tune into a snore fest. "I'm addicted to you, but you know that you're toxic." Zzzzzz.

Should Glee redo "Toxic" as "Toxoplasmosis"?

Toxoplasmosis is a disease from a protozoan parasite called T. gondii. Felines, aka cats, are the only animals in which T. gondii can reproduce. (I wonder why the musical Cats didn't have a character with toxoplasmosis?) If a kitty-cat swallows the parasite, the bug reproduces in the cat's intestines. The oocysts (like an egg) are then pooped out.

The prevalence of toxoplasmosis varies. In the USA, it's in about 15 percent of the population (and up to 50 percent in certain European countries). We get T. gondii by eating the oocysts from the cat litter box or contaminated dirt. Folks who live with three or more kittens are at increased risk of toxoplasmosis, though other studies show cat owners and non-cat owners have the same prevalence of the malady. 

Undercooked meat (such as ground beef or lamb) and unpasteurized goat milk can also infect a person with T. gondii. Pregnant women can transfer their toxoplasmosis to their babies, just as blood transfusions and organ transplantations can infect a person. 

Only 10 to 20 percent of people with normal immune systems will have symptoms with acute infection. Since T. gondii is never eliminated from the body, there's always a chance for symptoms to develop later in life. The main symptom is neck lymph node swelling, aka "swollen glands." They are non-tender and can be persistent for life. 

Sore throat, headache, body aches, body rash, fevers, chills, night sweats can develop to make a person look and feel like a hot mess. With the exception of the rash, these symptoms are so similar to the flu that it makes it hard to diagnose. Rarely, toxoplasmosis can wreak havoc on the lungs, heart, liver and brain. Most symptoms resolve on their own after weeks to months.

For immunocompromised people, especially those with AIDS, toxoplasmosis can cause significantly more problems. All HIV+ persons should be screened with a blood test for toxoplasmosis because there's a 30 percent risk of reactivation of the disease if the CD4 count drops below 100. 

The main problem for people with AIDS who have toxoplasmosis is CNS infection (in this case meaning brain abscess). Needless to say, headache is a common symptom as well as confusion, fever, and sometimes seizures. If the abscess increases the brain pressure, stroke symptoms can occur along with very bad mental status. An MRI is preferred to diagnose this. 

Toxoplasmosis can cause inflammation in the lungs; a dry cough with difficulty breathing is a symptom. Toxoplasmosis can also mimic CMV infection of the eye to decrease visual clarity so everything looks a little unclear– like Cybill Shepherd in Moonlighting. 

Antibiotics are very effective in treating toxoplasmosis and usually work within six weeks for brain infection. Steroids and anticonvulsants might have to be used in people with complications. Back in the days of AIDS in the early ‘90s, when I was a medical resident, toxoplasmosis of the brain was a disaster. Today with HAART (highly active antiretroviral therapy), I haven't seen any HIV-positive patient with brain toxoplasmosis. For people with CD4 counts less than 100, prophylactic antibiotics can help prevent reactivation of toxoplasmosis. 

"Toxic" is a great song, but it isn't great to experience: we can all do without toxic parents, toxic friends, toxic spouse, toxic kids, and especially toxic toxoplasmosis.


Dr. Hook cracks a joke or two, but he's a renowned physician with an interesting website, drjohnhong.com. Email him with your questions.