The risk for developing listerosis is five time higher in patients receiving cancer treatment than in other high-risk groups, and they should be offered advice on how to avoid food-borne infections, according to a study by British researchers.
Listerosis, caused by the bacterium Listeria monocytogenes is rare, but can be serious in patients with cancer or others with suppressed T-cell–mediated immunity due to the disease or its treatment.
In a study of the epidemiology of listerosis in England, Piers Mook of the Health Protection Agency, London, England, and associates identified 1413 patients (excluding pregnant women and their infants) diagnosed with listerosis between 1999 and 2009. Two-thirds (936) of patients had one or more underlying conditions.
A wide variety of conditions, including diabetes, AIDS, and liver or kidney disease, increased the risk for serious infection with L. monocytogenes, but the researchers found that more than one third of cases occurred in patients with cancer. The risk was nearly five times higher for cancer patients than for those with other underlying conditions. Patients with blood cancers were at highest risk. The findings are reported online in Emerging Infectious Diseases.
"Currently, patients who are receiving high doses of chemotherapy should be advised to take precautions to avoid food-borne infections,” said Martin Ledwick, of Cancer Research UK. “Although the findings suggest that this advice should be extended to all cancer patients having any type of treatment that compromises their immunity,” he continued, “it is not certain whether this precaution is absolutely necessary for all cancer patients.”
Patients can reduce their risk of listerosis by avoiding certain foods, including prepacked and sliced delicatessen meats; soft cheeses; smoked fish; pate; pre-prepared cooked and chilled meals; pre-prepared sandwiches; and unpasteurized milk.