Vasopressin in the cerebrospinal fluid of febrile children with or without seizures.

Immaturity in water and electrolyte balance in the brain has been considered to increase the susceptibility of young animals and children to febrile convulsions (FCs). Arginine-vasopressin (AVP) is involved in the regulation of several centrally mediated events such as modulation of fever and the ease with which water permeates into and out of the brain. To evaluate the possible role of AVP in the control of water balance and susceptibility to convulsions during fever we measured the AVP concentration in the cerebrospinal fluid (CSF) and plasma of febrile children with or without convulsions. The febrile population consisted of 47 children, of whom 29 experienced seizures during fever. Seven children with epileptic symptoms and 18 children without seizures were included as nonfebrile controls. The CSF AVP concentration in febrile children without seizures and in nonfebrile convulsive children was significantly lower (0.60 +/- 0.07 pmol/l, mean +/- SEM, P < 0.01 and 0.65 +/- 0.19 pmol/l, P < 0.05, respectively) than in nonfebrile children without convulsions (0.83 +/- 0.06 pmol/l). However, the levels of CSF AVP were not significantly different in children with FCs (0.71 +/- 0.06 pmol/l) compared with other groups. CSF AVP correlated with the CSF osmolality (r = 0.33, P = 0.02). No statistical differences in plasma AVP levels between the groups could be found. The present data provide support for the hypothesis of synchronous regulation of osmolality and AVP concentration in CSF. During fever the concentration of CSF AVP was lower in nonconvulsive children compared with nonfebrile nonconvulsive children. CSF AVP levels were not affected in febrile children by convulsions.