[Hydration and meningitis].

For almost 20 years, fluid restriction has been applied in the management of bacterial meningitis. This recommendation was based upon the findings of elevated plasma levels of arginine vasopressin in children with bacterial meningitis and their interpretation as evidence for inappropriate secretion of antidiuretic hormone. Recent data indicate that this interpretation was erroneous and that elevated levels of arginine vasopressin is the consequence of hypovolemia in the majority of cases of bacterial meningitis. In addition, fluid restriction appears to worsen the prognosis. As a consequence, not only fluid restriction must not be systematically applied in the management of bacterial meningitis, but appropriate fluid and sodium intakes are necessary to compensate hypovolemia and dehydration. Only a small number of cases with evidence of inappropriate secretion of antidiuretic hormone will require fluid restriction.