To the Editor:
We offer our thanks for the comments by Armstrong and SchepCitation1 on our article entitled “Myoclonic jerks due to acute bromovalerylurea intoxication.”Citation2 In fact, the exact mechanism of methyl bromide-induced central nervous system toxicity is not yet clearly understood.Citation3 Some authors suggested the toxicity is related to the disruption of enzymes involved in metabolic pathways responsible for the generation of energy.Citation4 However, the role of bromide in the methyl bromide intoxication is still unclear. Not only the theory of bromide replacing chloride ion in the neuronal cell but also the effect on the regional cerebral blood flow had been proposed.Citation5 Although the serum bromide level is poorly correlated with toxic effects of methyl bromide intoxication, history of exposure and high serum bromide level are still needed in the diagnosis of methyl bromide intoxication.Citation6 Armstrong and Schep misunderstood our article. The references mentioning that the low serum bromide level could be lethal in acute methyl bromide intoxication were cited to explain that the serum bromide level may be different between “acute” and “chronic” intoxication containing bromide. We did not mean to compare the serum bromide level between methyl bromide and other bromide intoxication.
References
- Armstrong D, Schep L. Comparing bromism with methyl bromide toxicity. Clin Toxicol 2009; 47.
- Lin JN, Lin HL, Huang CK, Lai CH, Chung HC, Liang SH, Lin HH. Myoclonic jerks due to acute bromovalerylurea intoxication. Clin Toxicol 2008; 46:861–863.
- Suwanlaong K, Phanthumchinda K. Neurological manifestation of methyl bromide intoxication. J Med Assoc Thai 2008; 91:421–426.
- Cavanagh JB. Methyl bromide intoxication and acute energy deprivation syndromes. Neuropathol Appl Neurobiol 1992; 18:575–578.
- Berglund M, Nielsén S, Risberg J. Regional cerebral blood flow in a case of bromide psychosis. Arch Psychiatr Nervenkr 1977; 223:197–201.
- Yamano Y, Nakadate T. Three occupationally exposed cases of severe methyl bromide poisoning: accident caused by a gas leak during the fumigation of a folklore museum. J Occup Health 2006; 48:129–133.