Health Encyclopedia

Cryptosporidium enteritis

Definition

Cryptosporidium enteritis is an infection of the small intestine that causes diarrhea. The parasite cryptosporidium causes this infection.

Alternative Names

Cryptosporidiosis

Causes

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:

People who take medicines to suppress their immune system
People with HIV/AIDS
Transplant recipients

In these groups, this infection is not just bothersome, but 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:

Animal handlers
People who are in close contact with infected people
Young children

Outbreaks have been linked to:

Drinking from contaminated public water supplies
Drinking unpasteurized cider
Swimming in contaminated pools and lakes

Some outbreaks have been very large.

Symptoms

Symptoms of infection include:

Abdominal cramping
Diarrhea, which is often watery, non-bloody, large-volume, and occurs many times a day
General sick feeling (malaise)
Malnutrition and weight loss (in severe cases)
Nausea

Exams and Tests

These tests may be done:

Antibody test to see if cryptosporidium is in the stool
Intestinal biopsy (rare)
Stool exam with special techniques (AFB staining)
Stool exam using a microscope to look for the parasites and their eggs

Treatment

There are several treatments for cryptosporidium enteritis.

Medicines such as nitazoxanide have been used in children and adults. Other medicines that are sometimes used include:

Atovaquone
Paromomycin

These medicines 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 HIV/AIDS, this can be done by using HIV-antiviral drugs. Using this type of treatment can lead to a complete remission of cryptosporidium enteritis.

Outlook (Prognosis)

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.

Possible Complications

These complications can occur:

Inflammation of a bile duct
Inflammation of the gallbladder
Inflammation of the liver (hepatitis)
Malabsorption (not enough nutrients being absorbed from the intestinal tract)
Inflammation of the pancreas (pancreatitis)
Loss of body mass that causes extreme thinness and weakness (wasting syndrome)

When to Contact a Medical Professional

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.

Prevention

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.

References

Huston CD. Intestinal protozoa. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 113.

Warren CA, Lima AAM. Cryptosporidiosis. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 329.

White AC. Cryptosporidiosis (Cryptosporidium species). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 282.

Review Date:3/10/2022
Reviewed By:Jatin M. Vyas, MD, PhD, Associate Professor in Medicine, Harvard Medical School; Associate in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997-A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

The Agency for Health Care Administration (Agency) and this website do not claim the information on, or referred to by, this site is error free. This site may include links to websites of other government agencies or private groups. Our Agency and this website do not control such sites and are not responsible for their content. Reference to or links to any other group, product, service, or information does not mean our Agency or this website approves of that group, product, service, or information.

Additionally, while health information provided through this website may be a valuable resource for the public, it is not designed to offer medical advice. Talk with your doctor about medical care questions you may have.