Listeriosis Health Article

Diagnosis

Listeriosis may be diagnosed and treated by infectious disease specialists and internal medicine specialists. The diagnosis and treatment of this infection should be covered by most insurance providers.

The only way to diagnose listeriosis is to isolate Listeria monocytogenes from blood, cerebrospinal fluid, or stool. A sample of cerebrospinal fluid is removed from the spinal cord using a needle and syringe. This procedure is commonly called a spinal tap. The amniotic fluid (the fluid which bathes the unborn baby) may be tested in pregnant women with listeriosis. This sample is obtained by inserting a needle through the abdomen into the uterus and withdrawing fluid. Listeria grows well in laboratory media, and test results can be available within a few days.

Treatment

Listeriosis is treated with the antibiotics ampicillin (Omnipen) or sulfamethoxazole-trimethoprim (Bactrim, Septra). Because the bacteria live within macrophage cells, treatment may be difficult, and the treatment periods may vary. Usually, pregnant women are treated for two weeks; newborns, two to three weeks; adults with mild disease, two to four weeks; persons with meningitis, three weeks; persons with brain abscesses, six weeks; and persons with endocarditis, four to six weeks.

Patients are often hospitalized for treatment and monitoring. Other drugs may be provided to relieve pain and fever and to treat other reactions to the infection.

Prognosis

The overall death rate for listeriosis is 26 percent. This high death rate is due to the serious illness suffered by newborns, the elderly, and immunocompromised persons. Healthy adults and older children have a low death rate. Complications of Listeria infection include: meningitis, sepsis, miscarriage, stillbirth, pneumonia, shock endocarditis, abscess (localized infection) formation, and eye inflammation.

Prevention

As of the early 2000s the United States government has done much to prevent listeriosis. Persons at extremely high risk (pregnant women, immunocompromised persons, etc.) must use extra caution. High risk persons should avoid soft cheeses, such as Mexican cheese, feta, Brie, Camembert, and blue cheese (cottage cheese is safe); thoroughly cook leftovers and ready-to-eat foods (such as hot-dogs); and avoid foods from the deli.

For all people, the risk of listeriosis can be reduced by taking these precautions:

• Completely cook all meats and eggs.
• Carefully wash raw vegetables before eating.
• Keep raw meat away from raw vegetables and prepared foods. After cutting raw meat, wash the cutting board with detergent before using it for vegetables.
• Avoid drinking unpasteurized milk or foods made from such milk.
• Wash hands thoroughly after handling raw meat.
• Follow the instructions on food labels. Observe food expiration dates and storage conditions.

BOOKS

Baltimore, Robert S. "Listeria monocytogenes." In Nelson Textbook of Pediatrics. Edited by Richard E. Behrman et al. Philadelphia: Saunders, 2004.

Lorber, Bennet. "Listeria monocytogenes." In Principles and Practice of Pediatric Infectious Diseases, 2nd ed. Edited by Sarah S. Long et al. St. Louis, MO: Elsevier, 2003.

PERIODICALS

Goldenberg, R. L. "The infectious origins of stillbirth." American Journal of Obstetrics and Gynecology 189 September 2003): 861–873.

Ressel, G. W. "CDC Issues recommendations for diagnosing, managing, and reporting foodborne illnesses." American Family Physician 86 (September 2004): 981–985.

WEB SITES

"Listeriosis." Centers for Disease Control. Available online at <www.cdc.gov/ncidod/dbmd/diseaseinfo/listeriosis_g.htm#greatrisk> (accessed January 7, 2005).

Belinda Rowland, PhD Rosalyn Carson-DeWitt, MD