Journal of Infection (1996) 33, 79-85 Is Amoxicillin-Cotrimoxazole the Most Appropriate Antibiotic Regimen for Listeria Meningoencephalitis? Review of 22 Cases and the Literature M. Merle-Melet .1, L. Dossou-Gbete ~, P. Maurer ~, Ph. Meyer ~, A. Lozniewski 2, O. Kuntzburger 1, M. Weber 2, A. Gerard ~ 1Department of Infectious Diseases, Brabois Hospital University Center; 54511 Vandoeuvre, and 2Laboratory of Bacteriology, Hospital University Center, 54000 Nancy, France Accepted for publication 13 March 1996 From June 1983 to January 1994, 22 adult patients with severe Listeria monocytogenes meningoencephalitis were observed in our Intensive Care Unit. Listeria monocytogenes was obtained in culture in cerebrospinalfluid or blood for every patient. Seven patients were treated with the combination ampicilIin-aminoglycoside (groupA) and 15 patients with the combination ampicillin (or amoxici]lin)-eotrimo)cazole (group A + C). Risk factors and gravity scones were similar in both groups. Failure of the 'gold standard' regimen (group A) was significantly higher (57%) compared to group A+C (6.7%) 0?<0.05). Mortality related to L. monocytogenes was 23.5% in group A compared to 6.7% in group A + C. Morbidity was reduced in group A+C (13.3%) compared to group A (60%) 07=0.15), This unique study seems to demonstrate that amo~ieillin-cotrimoxazole should be the most appropriate therapeutic regimen for Listeria meningoencephalitis. Introduction Infections with Listeria monocytogenes are increasing, due in part to changes in eating habits. Highly processed food, having extended shelf lives, could be the most likely vehicle for transmission of listeriosis. 1 Moreover, several studies have suggested that the incidence of L. mono- cgtogenes infections could increase in patients infected with the human immunodeficiency virus (HIV). e Despite the development of new bacterial identification methods and new antimicrobial agents, the overall mortality rate for L. monocytogenes meningoencephalitis is about 30- 35%. 3.4 Mortality for Listeria brain stem encephalitis could be higher, reaching 51%. s The literature review established that ampicillin (alone or combined with an aminoglycoside) represents the first line treatment for L. monocytogenes meningitis and brain stem encephalitis. 6 However, the combination ampicillin (A) or amoxicillin (Ax), with cotrimoxazole (C) (trimethoprim TMP, sulpha- methoxazole SMZ) is generally chosen in the treatment for L. monocytogenes meningitis or meningoencephalitis in our Department of Infectious Diseases, This retrospective study was designed: * Address correspondenceto: Dr M. Merle-Metet, MaladiesInfectieuseset R6animation-TD6, CHU de Brabots, 54511 VandoeuvreCedex, France. (i) To review all cases of severe L. monocBfogenes meningoencephalitis over a 10 year period. (ii) To compare the efficacy of the reference treatment A (or Ax) with the therapeutic regimen A (or Ax)+ C. In addition, we reviewed the clinical studies in order to assess a new therapeutic approach for severe neuro- meningeal listeriosis. Patients and Methods From June 1983 to January 1994, 22 patients with L. monocytogenes meningoencephalitis were admitted into our Intensive Care Unit. The criteria for including a patient in the study were: (1) meningitis with consciousness disturbances, mental disturbances, general seizures or focal neurologic signs (hemiplegia, cranial nerve involvement) and (2) iden- tification of L. monocytogenes in the cerebrospinal fluid (CSF) or blood. Antimicrobial susceptibilities were de- termined by the disk method. Exclusion criteria were defined as follows: no sign of encephalitis defined as above, allergy to fi-lactam antibiotics, antibiotic therapy duration less than 48 h, concurrent use of systemic antimicrobials effective on L. monocytogenes other than A, Ax, C or aminoglycosides (AG). 0163 4453/96/050079 +07 $12.00/0 © 1996 The British Society for the Study of Infection