CMV gastroenteritis or colitis is an inflammation of the stomach or intestine caused by infection with cytomegalovirus (CMV).

Cytomegalovirus (CMV) is present worldwide, and infections are very common. In the third world, CMV infection occurs at or near the time of birth. In more developed countries, infection usually occurs during infancy, but can occur in childhood or adolescence.

CMV is transmitted in situations of close interpersonal contact. The virus has been isolated in nearly all organs and body fluids in the human body. By adulthood, up to 80% of the population has anti-CMV antibodies, which indicates prior infection.

CMV infection in people with healthy immune systems usually produces no symptoms. However, a flu-like syndrome can occur. In rare instances, more severe CMV infection, involving the GI tract, has been reported in people with normal immunity.

Patients with CMV colitis show symptoms such as fever, bloody diarrhea, and abdominal pain. When CMV colitis occurs in patients with normal immune systems, they typically have other serious medical problems, such as severe trauma, renal failure, or infection.

A special category of patients -- those who have inflammatory bowel diseases such as Crohn's disease and ulcerative colitis -- can suffer from gastrointestinal CMV infections. A small number of patients who have undergone colectomy for ulcerative colitis have been found to have symptomatic CMV infections in their remaining intestine.

CMV infections of the GI tract that cause symptoms are more common in those with impaired immune systems, and in these patients serious infections can occur.

People at risk include those with AIDS, recipients of organ transplants (overall incidence between 2-16%) or bone marrow transplants (overall incidence between 32-52%), and people receiving chemotherapy or other immunosuppressive treatments. Immunocompromised people who develop CMV gastroenteritis and colitis can have severe illness.

GASTROINTESTINAL CMV INFECTION

Gastrointestinal CMV disease may be localized (affecting one area) or widespread (throughout the body). Ulcers can occur in the esophagus, stomach, small intestine, or colon. Additionally, overt gastritis (inflammation of the stomach) and colitis (inflammation of the colon) may also occur.

Typically, ulcerations in the upper GI tract (esophagus, stomach) are associated with symptoms of nausea and vomiting, pain on swallowing (odynophagia), difficulty swallowing (dysphagia), or abdominal pain.

When the intestines are involved, the ulcerations may cause abdominal pain, diarrhea, or bloody stools. More severe infections can result in gastrointestinal bleeding or perforation (a hole through the wall of the infected organ).

• Fever
• Diarrhea
• Nausea and vomiting
• Abdominal pain
• Swallowing difficulty or pain with swallowing
• Weight loss
• Gastrointestinal bleeding

• Identification of CMV on tissue biopsy
• Viral culture of tissue biopsy (esophageal, gastric, duodenal, or colonic) or other samples.
• DNA in situ hybridization or PCR of tissue biopsy specimen
• CMV antigen assay (blood, urine, other fluids)
• Upper endoscopy
• Colonoscopy
• CMV serology by IFA
• Upper GI and small bowel series
• Barium enema
• Stool culture to rule out other organisms

The goals of therapy are to control the infection and relieve symptoms. Antiviral medications that may be used include ganciclovir (Cytovene) and foscarnet (Foscavir). Treatment is given intravenously (into a vein) and sometimes orally for several weeks.

In some cases, therapy may be prolonged. CMV hyperimmune globulin may be used in cases of severe refractory infection (when other drugs don't work). Antidiarrheal medications and analgesics (pain killers) are used for the relief of symptoms.

Nutritional supplements or intravenous nutrition (putting nutrients directly into the blood stream) may be used to combat wasting.

In people with normal immune systems, symptoms usually go away without treatment. In those with suppressed immune systems, symptoms are more severe. The outcome depends upon the severity of the immunodeficiency and the severity of the infection.

People with AIDS may have a worse outcome than those with a different type of immunodeficiency. CMV infection typically affects the entire body, even if patients only have GI symptoms. Therefore, overall outcome depends on the response to therapy with antiviral drugs.

Low white blood cell count may occur with use of ganciclovir. Kidney problems may occur with the use of foscarnet.

Call for an appointment with your health care provider if symptoms develop that are suggestive of CMV gastroenteritis.

There is a significant risk of CMV infection in people who are antibody-negative and subsequently receive an organ from a CMV-positive donor.

Both ganciclovir (Cytovene) and valacyclovir (Valtrex) -- given orally before the transplant -- can decrease the likelihood of a new infection or reactivation of an old infection in patients who have received organ or bone marrow transplants, as well as in patients with AIDS.

Cytomegalovirus hyperimmune globulin may be given to bone marrow transplant or renal transplant recipients who fail to respond to antiviral therapy.