Cryptosporidium enteritis is an infection of the small intestine that causes diarrhea. The parasite cryptosporidium causes this infection.
Cryptosporidium has recently been recognized as a cause of diarrhea worldwide in all age groups. It has a greater effect on people with a weakened immune system, including:
In these groups, this infection is not just bothersome. It also can lead to severe and life-threatening loss of muscle and body mass (wasting) and malnutrition.
The major risk factor is drinking water that is contaminated with feces (stool). People at higher risk include:
Outbreaks have been linked to:
Some outbreaks have been very large.
Symptoms of infection include:
These tests may be done:
There are several treatments for cryptosporidium enteritis.
Drugs such as nitazoxanide have been used in children and adults. Other drugs that are sometimes used include:
These drugs often help only for a little while. It is common for the infection to return.
The best approach is to improve immune function in people who have a weakened immune system. In people with AIDS, this can be done by using highly active antiviral therapy. It can lead to a complete remission of cryptosporidium enteritis.
In healthy people, the infection will clear up, but it can last up to a month. In people with a weakened immune system, long-term diarrhea may cause weight loss and malnutrition.
These complications can occur:
Contact your health care provider if you develop watery diarrhea that does not go away within a few days, especially if you have a weakened immune system.
Proper sanitation and hygiene, including handwashing, are important measures for preventing this illness.
Certain water filters can also reduce risk by filtering out the cryptosporidium eggs. However, the pores of the filter must be smaller than 1 micron to be effective. If you have a weakened immune system, ask your provider if you need to boil your water.
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White AC Jr. Cryptosporidiosis (Cryptosporidium species). In: Mandell GL, Bennett JE, Dolin R, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 8th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 284.
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Last reviewed on: 3/13/2016
Reviewed by: Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.