Enhanced neutrophil function in children on bromide therapy

The final step in neutrophil bacterial killing is formation of a toxic halide complex. For this reason, we studied neutrophil function in children receiving bromide anticonvulsant therapy. Whole blood and serum were obtained from 7 patients with seizure disorders treated orally with triple bromide elixir to examine neutrophil function as measured by luminol enhanced chemiluminescence (CL). Serum bromide concentrations [Br-] were determined concomitantly. There was a direct correlation between [Br-] and CL activity of neutrophils (r = 0.87) with peak CL responses significantly higher than controls when [Br-] were in the therapeutic range (10-20 mM). With [Br-] above 25 mM, CL activity was reduced. Serum from patients also enhanced CL of control neutrophils with a similar relationship to measured [Br-]. To confirm that enhanced neutrophil activity was attributable to [Br-] use, [Br-] ranging from 0-50 mM were added to control neutrophils in otherwise normal physiologic conditions and the CL assay was performed. Results expressed as percent of control values were as follows: [Br-] 5 mM, 110%; 10 mM, 158%; 15 mM, 194%; 20 mM, 252%; 25 mM, 136%; 30 mM, 364%; and 50 mM, 205%. These data demonstrate that Br- enhances phagocytic and bactericidal activity of neutrophils and suggest that Br- therapy may augment host defense capabilities.