CASE REPORT Treatment difficulties of a listerial rhombencephalitis in an adult patient allergic to penicillins

T he microorganism Listeria monocytogenes is a common cause of central nervous system (CNS) infections associated with an unfavourable prognosis; series published in the past decade indicate a lethality of 12–43%. 2 Overall, acute meningitis is the most frequently encountered form of listerial CNS infection, but healthy adults more frequently develop rhombencephalitis (RE). Optimal treatment for RE is not yet defined because bacterial resistance and the blood–brain barrier limit the efficiency of antimicrobials. Many consider a combination of ampicillin and gentamicin as the ‘‘gold standard’’, although some reports have found that aminopenicillin together with trimethoprimsulfamethoxazole (TMP/STX) is at least as good. 4 Corticosteroids, usually avoided, are now being reconsidered because anecdotal case reports have shown that listeria induced neurological lesions have a good response to dexamethasone.