Subdural effusion and its relationship with neurologic sequelae of bacterial meningitis in infancy: a prospective study.

One hundred thirteen infants, aged 1 to 18 months, were screened systematically and serially using transillumination for the presence of subdural effusion during acute bacterial meningitis due to Haemophilus influenzae type b, Streptococcus pneumoniae, or Neisseria meningitidis. Effusion developed in 44 (39%) of the patients during the course of treatment. Young age, rapid onset of illness, low peripheral white blood cell count, and high cerebrospinal fluid levels of protein and bacterial antigen were associated with a higher likelihood of developing effusion. Although patients with effusion were more likely to have neurologic abnormalities both at the time of admission and at completion of therapy, and were more likely to have seizures during the course of treatment, there was no greater incidence of seizures, hearing loss, neurologic deficits, or developmental delay on longterm follow-up (median follow-up interval 5.5 years) in patients with effusion. Specific invasive therapy is not indicated in infants with meningitis and subdural effusion who are otherwise improving.

Oral water intoxication in infants. An American epidemic.

Between 1975 and 1990, a total of 34 patients with water intoxication were treated at St Louis (Mo) Children's Hospital, 24 of these in the last 3 years, indicating a marked increase in incidence of this previously rare condition. Thirty-one were infants living in poverty who ingested excessive amounts of water offered at home by their caretakers. Exhaustion of the supply of infant formula was the most common reason given for this substitution. Infants were treated by a single infusion of hypertonic saline or a slow infusion of isotonic saline. Central pontine myelinolysis was not observed as a complication of hypertonic saline therapy. Modification of the Special Supplemental Food Program for Women, Infants, and Children to provide sufficient formula for the growing infant and better education of mothers as to the hazards of excessive water ingestion might reduce the incidence of this preventable and life-threatening condition.

Incidence of seizures that follow rehydration of hypernatremic rabbits with intravenous glucose or fructose solutions.

Hypernatremic dehydration was induced in rabbits during a 3- to 5-day period resulting in mean plasma sodium concentrations of 187 meq/liter. The animals were then rehydrated during a 4-h period by intravenous administration of a 2.5% glucose or fructose solution. The water content of four regions of brain sample showed a significant (P less than 0.05) increase in brain water content above normal in the rehydrated groups. Brain water content was significantly (P less than 0.01) greater in those animals with seizures compared with those without seizures, suggesting the importance of water intoxication in the pathogenesis of seizure activity. Changes in muscle Na, K, Cl, and water content were not similar to those of brain, indicating that muscle content of these substances was not an accurate reflection of the brain content specific time. The incidence of seizures was significantly (P less than 0.05) greater when glucose solution was used for rehydration (49%) compared with the use of fructose solution (25%). The mechanism(s) by which fructose resulted in a lower incidence of seizures is not known. The frequency of seizure activity was directly proportional to the rate of administration of intravenous solutions utilized to correct hypernatremia. In addition, the specific carbohydrate of the solution appeared to play an important role in the pathophysiology of the development of seizures.

The incidence of seizures after rehydration of hypernatremic rabbits with intravenous or ad libitum oral fluids.

Hypernatremic dehydration (mean plasma sodium, 184 mEq/L) was produced over a 3-5 d period in 71 rabbits. The dehydrated animals were divided into groups and rehydrated by intravenous (4, 6, and 8 h duration) or oral (4 and 24 h duration) solutions in amounts calculated to return plasma Na to 140 mEq/L. Plasma was obtained serially from each animal for electrolyte and osmolality determinations during dehydration and rehydration. Samples of brain hemisphere and cortex were obtained for chemical analysis from every animal immediately after death. The incidence of seizures was significantly less (P less than 0.025) in rabbits rehydrated orally when compared with rabbits rehydrated by the intravenous route. Brain water content was significantly greater in rabbits rehydrated intravenously when compared with normal rabbits and rabbits rehydrated orally. In addition, the amount of brain water was greater in rabbits with seizures when compared with those which did not have seizure manifestations. The mechanism underlying the significant reduction in seizures when the animals were rehydrated orally may relate to an integration of drinking behavior with rehydration status. Administration of oral fluids may provide an effective method of therapy for some patients with hypernatremic dehydration.

Seizures and other neurologic sequelae of bacterial meningitis in children.

BACKGROUND: Although the mortality rate among children with bacterial meningitis has decreased dramatically in recent decades, some patients are left with neurologic sequelae. It has not been clearly established which features of the acute illness predict the chronic neurologic sequelae, including late seizures or epilepsy. METHODS: We followed 185 infants and children prospectively during and after acute bacterial meningitis. The mean duration of follow-up was 8.9 years (range, 0.1 to 15.5). During the first six years standard neurologic examinations were performed; telephone interviews were conducted thereafter. RESULTS: One month after meningitis, 69 children (37 percent) had neurologic abnormalities. Many of these signs resolved within a year, leaving only 26 children (14 percent) with persistent deficits: 18 (10 percent) had only sensorineural hearing loss, and 8 (4 percent) had multiple neurologic deficits. Thirteen children (7 percent) had one or more late seizures not associated with fever. The presence of persistent neurologic deficits indicative of cerebral injury was the only independent predictor of late afebrile seizures (P less than 0.001). CONCLUSIONS: After bacterial meningitis only children with permanent neurologic deficits are at high risk for epilepsy. Those with normal examinations after the acute illness have an excellent change of escaping serious neurologic sequelae, including epilepsy.

Prospective evaluation of hearing impairment as a sequela of acute bacterial meningitis.

As part of a prospective study of acute bacterial meningitis in children, we studied for five years the hearing of 185 infants and children who had acute bacterial meningitis when they were more than one month of age. Nineteen (10.3 per cent) of the patients had persistent bilateral or unilateral sensorineural hearing loss. The incidence of hearing loss as determined by electric-response audiometry and conventional tests was 31 per cent with Streptococcus pneumoniae, 10.5 per cent with Neisseria meningitidis, and 6 per cent with Hemophilus influenzae infections. Transient conductive hearing impairment was found in 16 per cent of the sample, but in no case was there apparent improvement in a sensorineural deficit over time. The site of disease resulting in impaired hearing cannot be stated with certainty, but involvement of the inner ear or auditory nerve was suspected. The number of days of illness (symptoms) before hospitalization and institution of antibacterial treatment was not correlated with the development of sensorineural deafness.