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For further information, see CMDT Part 35-08: Listeriosis
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Essentials of Diagnosis
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Ingestion of contaminated food product
Fever in a pregnant woman in her third trimester
Altered mental status and fever in an older or immunocompromised patient
Blood and cerebrospinal fluid cultures confirm diagnosis
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General Considerations
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Listeria monocytogenes is a facultative, motile, gram-positive rod capable of invading several cell types and causing intracellular infection
Most cases of infection are sporadic, but outbreaks have been traced to eating contaminated food, including
Unpasteurized dairy products
Hot dogs
Delicatessen meats
Cantaloupes
Soft cheeses, such as queso fresco, brie, and ricotta
Outbreaks have been associated with significant morbidity and mortality in infected persons
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Positive blood or cerebrospinal fluid culture
In meningitis, cerebrospinal fluid often shows a lymphocytic pleocytosis, with variable protein and glucose findings
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Tables 32–5 and 32–3
Drug of choice is ampicillin, 8–12 g/day intravenously in four to six divided doses (the higher dose is recommended in cases of meningitis)
Gentamicin, 5 mg/kg/day intravenously once or in divided doses
Trimethoprim-sulfamethoxazole
Therapy should be administered for at least 2–3 weeks
Longer durations—between 3 and 6 weeks—are recommended for treatment of meningitis, especially in immunocompromised persons
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