EVIDENCE FOR FLUID VOLUME DEPLETION IN HYPONATREMIC PATIENTS WITH BACTERIAL-MENINGITIS

Since the mechanisms underlying hyponatraemia in meningitis are poorly understood, we retrospectively reviewed the records of 187 paediatric patients with bacterial meningitis treated at the Department of Pedia trics, University of Bern, Switzerland, between 1982 and 1994. The deg ree of dehydration calculated from naked weight on admission and at 5 days was consistently (by 2.8 x 10(-2)) and significantly more pronoun ced in 30 hyponatraemic (plasma sodium 130 mmoll(-1) or less) than in 157 normonatraemic patients (plasma sodium 131 mmoll(-1) or more). Fur thermore, a tendency towards reduced sodium excretion was noted in hyp onatraemic patients. The results suggest that in bacterial meningitis hyponatraemia is mostly induced by clinically latent fluid volume depl etion.