[Rombencephalitis due to Listeria monocytogenes. Probable usefulness of dexamethasone associated with antibiotic treatment].

INTRODUCTION: Infection of the central nervous system by Listeria monocytogenes appears in most cases as acute meningitis which is indistinguishable from other types of acute meningitis. Rombencephalitis is a rare form of neurolisteriosis, localized to the brainstem. The initial non specific symptoms may make early diagnosis difficult.

CASE REPORT: We describe the clinical case of a previously healthy woman who had L. monocytogenes infection localized to the brainstem. Her initial symptoms were fever and headache followed by signs of brainstem involvement, deterioration of consciousness and severe respiratory insufficiency which made mechanical ventilation necessary. Study of the cerebrospinal fluid showed lymphocytic pleocytosis, raised protein and normal glucose levels. L. monocytogenes was isolated on blood culture. Cranial computerized tomography was normal and magnetic resonance showed a right pontobulbar lesion. After receiving specific antibiotic treatment the infectious condition improved. However, the neurological symptoms started to improve when dexamethasone was added to the antibiotic treatment twelve days later. The patient was discharged from hospital with slight neurological sequelas.

CONCLUSION: In a febrile patient with signs of brainstem involvement, neurolisteriosis should be suspected and ampicillin and gentamycin added to the treatment. The possibility of acute respiratory arrest occurring makes it necessary to monitor these patients closely. The association of dexamethasone to the antibiotic treatment may be useful in some cases of rombencephalitis due to L. monocytogenes.