Markowitz M E, Rosen J F
Department of Pediatrics, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York 10467.
J Pediatr. 1991 Aug;119(2):305-10. doi: 10.1016/s0022-3476(05)80750-4.
We evaluated the recommendation of the Centers for Disease Control, that children with moderate lead poisoning undergo the lead mobilization test (LMT) to determine the need for a full course of chelation treatment. Current criteria for selection for this test include a blood Pb concentration (bPb) between 25 and 55 micrograms/dl and an erythrocyte protoporphyrin level greater than 35 micrograms/dl. To determine whether the eligibility criteria could be refined to a smaller group of patients, we compared bPb determinations obtained on the day of the LMT in 198 children with moderate Pb poisoning to the results of the LMT. We found that children with bPb less than 25 micrograms/dl were unlikely to respond to the test dose of calcium disodium ethylenediamine tetraacetate with a Pb diuresis (24/25 patients had low urinary Pb excretion on the LMT). In contrast, 88% of children with bPb greater than or equal to 40 micrograms/dl were likely to excrete sufficient Pb to indicate the need for a full course of chelation. We conclude that the LMT is indicated for children with bPbs between 25 and 40 micrograms/dl. Children with bPb between 40 and 55 micrograms/dl may receive chelation therapy without having an LMT, if the performance of the LMT is not practical. Patients with levels less than 25 micrograms/dl should be followed clinically and removed from further Pb exposure.
我们评估了疾病控制中心的建议，即中度铅中毒儿童应进行铅动员试验（LMT），以确定是否需要进行全程螯合治疗。目前该试验的入选标准包括血铅浓度（bPb）在25至55微克/分升之间，以及红细胞原卟啉水平大于35微克/分升。为了确定入选标准是否可以细化到更小的患者群体，我们将198名中度铅中毒儿童在进行LMT当天的bPb测定结果与LMT结果进行了比较。我们发现，bPb低于25微克/分升的儿童不太可能对依地酸钙钠试验剂量产生铅利尿反应（25名患者中有24名在LMT时尿铅排泄量低）。相比之下，bPb大于或等于40微克/分升的儿童中有88%可能排泄足够的铅，表明需要进行全程螯合治疗。我们得出结论，LMT适用于bPb在25至40微克/分升之间的儿童。如果进行LMT不实际，bPb在40至55微克/分升之间的儿童可以在不进行LMT的情况下接受螯合治疗。血铅水平低于25微克/分升的患者应进行临床随访，并避免进一步接触铅。
