Correspondence
La Crosse Encephalitis in Children
N Engl J Med 2001; 345:148-149July 12, 2001
- Article
To the Editor:
McJunkin et al. (March 15 issue)1 report that in patients with La Crosse encephalitis who have clinical deterioration, it follows the development of hyponatremia. This observation underscores the danger of administering hypotonic maintenance fluids in children. The hyponatremia in these patients may have been iatrogenic, since they presented with normal serum sodium levels.
The administration of hypotonic fluids in children can be lethal2 for many reasons. Many hospitalized children have impaired excretion of free water as a result of either the syndrome of inappropriate antidiuretic hormone secretion due to pulmonary or central nervous system disease or physiologic increases in vasopressin production due to volume depletion, pain, stress, nausea, narcotic agents, or the postoperative state. The administration of hypotonic fluids will result in natriuresis with retention of free water, and hyponatremia will develop. In children with hyponatremia, signs of hyponatremic encephalopathy develop at higher serum sodium levels than those in adults because of physical factors, including an increased ratio of brain size to skull size.
The routine use of hypotonic fluids in hospitalized children can be dangerous. We believe that this practice should be abandoned in favor of the administration of isotonic saline and that the serum sodium level should be monitored closely.
2 ReferencesMichael L. Moritz, M.D.
Children's Hospital of Pittsburgh, Pittsburgh, PA 15213
moritzm@chplink.chp. edu J.C. Ayus, M.D.
Baylor College of Medicine, Houston, TX 770191
McJunkin JE ,de los Reyes EC ,Irazuzta JE , et al. La Crosse encephalitis in children. N Engl J Med 2001;344:801-807
Full Text | Web of Science | Medline2
Arieff AI ,Ayus JC ,Fraser CL . Hyponatremia and death or permanent brain damage in healthy children. BMJ 1992;304:1218-1222
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Author/Editor Response
The authors reply:
To the Editor: The decline in the mean serum sodium level in the group of children in our study who had clinical deterioration (from 138 to 134 mmol per liter) is relatively small as compared with that in the study cited by Moritz and Ayus, which involved previously healthy children hospitalized for surgical procedures (mean decline, from 138 to 115 mmol per liter). Nevertheless, we agree that even relatively small changes in serum sodium may be clinically important.
Our findings, although limited by a retrospective study design, did stand the test of a comparison with the findings in a matched control group (not reported because of space constraints).
We did, in fact, recommend the use of isotonic fluids in our discussion, particularly since there is no clear consensus in the literature on whether isotonic fluids should be used in children with central nervous system infection. Of the 13 children in our study who had deterioration after admission to the hospital, most had started to receive 0.45 percent sodium chloride with 5 percent dextrose at roughly 80 percent of maintenance requirements (if there was no dehydration or ongoing fever). This strategy for the administration of fluids was generally that used in the study population as a whole and reflects standard management practices during the study period (1987 through 1996),1 although fluids were minimally restricted.
In one of the few prospective studies of parenteral fluid therapy in patients with bacterial meningitis, 0.2 percent sodium chloride with 5 percent dextrose was administered as the initial therapy.2 In that study, patients who had hyponatremia on admission had improvement in serum sodium levels, especially if fluids were restricted (65 to 70 percent of maintenance requirements), but there was a trend toward a lower rate of survival without impairment in the patients in whom fluids were restricted. The growing evidence against initial fluid restriction in patients with central nervous system infection2-4 makes recommendations for the use of isotonic fluids even more important, as we noted.
If, as our data suggest, mild-to-moderate hyponatremia is associated with clinical deterioration, it may be appropriate to redefine the acceptable range of serum sodium levels in children with central nervous system infection, in order to encourage earlier intervention. Information from our study suggests that the sodium level should be closely monitored and that isotonic fluids should be used as the initial intravenous fluid therapy in children with La Crosse encephalitis. Prospective studies of fluid therapy in patients with central nervous system infection should examine the use of isotonic fluids and might also evaluate the judicious, nonemergency use of hypertonic saline to maintain serum sodium levels and osmolality values within a defined range. The latter approach has been studied prospectively in children with closed head injuries.5
5 ReferencesJames E. McJunkin, M.D.
West Virginia University School of Medicine, Morgantown, WV 26506-9214
jmcjunkin@hsc.wvu. edu Jose Irazuzta, M.D.
Children's Medical Center, Dayton, OH 45408-1815Ann E. Thompson, M.D.
University of Pittsburgh Medical Center, Pittsburgh, PA 152131
Rogers MD, Nichols DG, eds. Textbook of pediatric intensive care. 3rd ed. Baltimore: Williams & Wilkins, 1996:1055.
2
Singhi SC ,Singhi PD ,Srinivas B , et al. Fluid restriction does not improve the outcome of acute meningitis. Pediatr Infect Dis J 1995;14:495-503
CrossRef | Web of Science | Medline3
Powell KR ,Sugarman LI ,Eskenazi AE , et al. Normalization of plasma arginine vasopressin concentrations when children with meningitis are given maintenance plus replacement fluid therapy. J Pediatr 1990;117:515-522
CrossRef | Web of Science | Medline4
Bianchetti MG ,Thyssen HR ,Laux-End R ,Schaad UB . Evidence for fluid volume depletion in hyponatraemic patients with bacterial meningitis. Acta Paediatr 1996;85:1163-1166
CrossRef | Web of Science | Medline5
Simma B ,Burger R ,Falk M , et al. A prospective, randomized, and controlled study of fluid management in children with severe head injury: lactated Ringer's solution versus hypertonic saline. Crit Care Med 1998;26:1265-1270
CrossRef | Web of Science | Medline
- Citing Articles (11)
Citing Articles
1
Michael L. Moritz, Juan Carlos Ayus. (2010) New aspects in the pathogenesis, prevention, and treatment of hyponatremic encephalopathy in children. Pediatric Nephrology 25:7, 1225-1238
CrossRef2
Michael L. Moritz, Juan Carlos Ayus. (2010) 100 cc 3% sodium chloride bolus: a novel treatment for hyponatremic encephalopathy. Metabolic Brain Disease 25:1, 91-96
CrossRef3
Michael L. Moritz, Juan Carlos Ayus. (2010) Water Water Everywhere: Standardizing Postoperative Fluid Therapy with 0.9% Normal Saline. Anesthesia & Analgesia 110:2, 293-295
CrossRef4
Michael L. Moritz, Juan Carlos Ayus. 2009. Diabetes Insipidus and SIADH. , 261-286.
CrossRef5
Juan Carlos Ayus, Michael L Moritz. (2008) Exercise-Associated Hyponatremia Masquerading as Acute Mountain Sickness: Are We Missing the Diagnosis?. Clinical Journal of Sport Medicine 18:5, 383-386
CrossRef6
Julia Granerod, Natasha S. Crowcroft. (2007) The epidemiology of acute encephalitis. Neuropsychological Rehabilitation 17:4-5, 406-428
CrossRef7
Michael L Moritz, Juan Carlos Ayus. (2007) Hospital-acquired hyponatremia—why are hypotonic parenteral fluids still being used?. Nature Clinical Practice Nephrology 3:7, 374-382
CrossRef8
Michael L. Moritz, J. Carlos Ayus. (2005) Preventing neurological complications from dysnatremias in children. Pediatric Nephrology 20:12, 1687-1700
CrossRef9
Stephen D Playfor. (2004) Hypotonic intravenous solutions in children. Expert Opinion on Drug Safety 3:1, 67-73
CrossRef10
M. L. Moritz. (2003) The pathophysiology and treatment of hyponatraemic encephalopathy: an update. Nephrology Dialysis Transplantation 18:12, 2486-2491
CrossRef11
Douglas H. Graham, Jennifer L. Holmes, Barry J. Beaty, William C. Black. (2003) Quantitative trait loci conditioning transovarial transmission of La Crosse virus in the eastern treehole mosquito, Ochlerotatus triseriatus. Insect Molecular Biology 12:4, 307-318
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