Cryptosporidium infection (cryptosporidiosis) is a gastrointestinal disease whose primary symptom is diarrhea. The illness begins when the tiny cryptosporidium parasites enter your body and travel to your small intestine. Cryptosporidium (krip-toe-spo-RID-ee-um) then begins its life cycle inside your body — burrowing into the walls of your intestines and then later being shed in your feces.
In most healthy people, a cryptosporidium infection produces a bout of watery diarrhea and the infection usually goes away within a week or two. If you have a compromised immune system, a cryptosporidium infection can become life-threatening without proper treatment.
You can help prevent cryptosporidium by practicing good hygiene and by avoiding drinking water that hasn't been boiled or filtered.
The first signs and symptoms usually appear two to seven days after infection with cryptosporidium and may include:
Symptoms may last for up to two weeks, though they may come and go sporadically for up to a month, even in people with healthy immune systems. Some people with cryptosporidium infection may have no symptoms.
When to see a doctor
Cryptosporidium infection begins when you ingest the cells of one of nearly a dozen species of the one-celled cryptosporidium parasite. The Cryptosporidium parvum (C. parvum) species is responsible for the majority of infections in humans.
These parasites then travel to your intestinal tract, where they settle into the walls of your intestines. Eventually, more cells are produced and shed in massive quantities into your feces, where they are highly contagious.
You can become infected with cryptosporidium by touching anything that has come in contact with contaminated feces. Methods of infection include:
If you have a compromised immune system from HIV/AIDS, you're more susceptible to illness from cryptosporidium than is a person with a healthy immune system. People with HIV/AIDS can develop severe symptoms and a chronic, persistent form of disease that may be difficult to treat.
People who are at increased risk of developing cryptosporidiosis include:
Complications of cryptosporidium infection include:
Cryptosporidium infection itself isn't life-threatening. However, if you've had a transplant or if you have a weakened immune system, developing complications can be dangerous.
Preparing for your appointment
You're likely to start by seeing your primary physician. However, in some cases, he or she may refer you to a doctor who specializes in infectious diseases or a doctor who specializes in disorders of the gastrointestinal tract (gastroenterologist).
Here's some information to help you get ready for your appointment, and what to expect from your doctor.
What you can do
Your time with your doctor is limited, so preparing a list of questions can help you make the most of your time together. For cryptosporidiosis, some basic questions to ask your doctor include:
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something.
What to expect from your doctor
What you can do in the meantime
Tests and diagnosis
You may undergo the following tests to diagnose cryptosporidium infection:
Treatments and drugs
There's no commonly advised specific treatment for cryptosporidiosis, and recovery usually depends on the health of your immune system. Most healthy people recover within two weeks without medical attention.
If you have a compromised immune system, the illness can last and lead to significant malnutrition and wasting. The goal of treatment is to alleviate symptoms and improve your immune response. Cryptosporidium treatment options include:
Cryptosporidium infection is contagious, so take precautions to avoid spreading the parasite to other people.
All preventive methods aim to reduce or prevent the transmission of the cryptosporidium germs that are shed in human and animal feces. Precautions are especially important for people with compromised immune systems. Follow these suggestions:
Always refrain from swimming anytime you're experiencing diarrhea. If you know you've had a cryptosporidium infection, don't go swimming for at least two weeks after your symptoms subside because you may still be contagious.
Last Updated: 2011-03-04
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