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Diarrhea in Pregnancy: Listeria Infection


After eating some salads and cheese at a farewell party for a colleague a few days ago, T, a 32-year-old mum-to-be began to feel unwell. She had lost her appetite the next day and started to have diarrhea 2 to 3 times a day. She took some medications for food poisoning from her family physician. The symptoms did not subside, Instead, she started to have fever with chills and rigor. She was then admitted to the hospital for further investigation.

T was in her second trimester of pregnancy. Other than the slight dehydration and a raised temperature of 38 deg C, her vital signs were normal. The fetus was active and well with a heart rate of 160 beats per minute. There was no stiff neck or severe headache to suggest infection of her nervous system. Blood culture was positive for Listeria.

Listeria infection (Listeriosis) Listeriosis is an infection caused by eating food contaminated with the germ called Listeria monocytogenes.

Pregnant women are much more susceptible to listeria infections than are healthy adults. During pregnancy, it usually causes mild symptoms in the mother. The consequences for the foetus however, can be serious. It can end up with miscarriage, stillborn, premature birth or severe life-threatening infection soon after birth. Symptoms of Listeriosis Symptoms usually appear a few days after consuming the contaminated food. Occasionally, it can take 30 days or more before symptoms of infection begin.

Fever and muscle aches are common; sometimes preceded by diarrhea or other gastrointestinal symptoms. In severe infection, inflammation of the membranes covering the brain and spinal cord called meningitis may occur. The symptoms include

  • Severe headache

  • Stiff neck

  • Confusion or sensitivity to light

  • Convulsion

Diagnosis and treatment Listeria bacteria can be diagnosed by blood culture. In some cases, samples of urine or spinal fluid can be tested for the bacteria as well. During pregnancy, antibiotic treatment should be given to prevent the infection from affecting the baby. Prevention Listeria bacteria can be found in moist environments, soil, water, decaying vegetation and animal feces. It can survive and even grow under refrigeration, freezing and other food preservation measures.

People can get infected by eating contaminated raw vegetables, deli meat, unpasteurized milk, cheese, hot dogs and smoked seafood To prevent Listeriosis, simple food safety guidelines should be followed:

  • Avoid uncooked food

  • Keeps things clean: including refrigerator, cooking utensils, cutting board and hands.

  • Wash raw vegetables thoroughly and cook the food to a safe temperature.

T was given antibiotics and probiotics promptly and was hydrated with fluid intravenously. Fever and diarrhea subsided on the 3rd day after admission. She was discharged well. Her antenatal course remained uneventful. The fetus grew satisfactorily without complications. She is in her last trimester now.