Journal of Pediatrtics
Volume 45
Pages 297-298

The use of disodium calcium ethylenediaminetetraacetate (CaEDTA), an organic chelating agent, has been reported in the treatment of lead intoxication,^{1, 2, 3} The ability of the agent to chelate lead, the ready excretion of water-soluble chelates and the absence of toxic effects because of the nonionizable stable complex formed with lead prompted the use of CaEDTA in this field.

Sidbury and associates⁴ first reported the used of oral CaEDTA in lead intoxication. These workers administered the drug to a total of seven patients, two of whom were children. Intravenous and oral methods of administration to the children were used alternately during the same course of treatment. Their results indicated that oral CaEDTA produced a five-to-tenfold increase in twenty-four-hour urinary lead excretion with maximum excretion occurring on the third or fourth day. Intravenous CaEDTA, however, produced a ten-to-fortyfold increase in urinary lead excretion with maximal excretion being reached in the first twenty-four hours following administration.

The present study reports the effect of oral CaEDTA used alone on five cases of chronic lead intoxication in children.

Children with a documented history of eating paint and/or plaster of a toxic lead content were selected from the Developmental Clinic of the Pediatric Department. Confirmation of lead intoxication was determined through blood lead levels roentgenograms of the long bones, urinary coproporphyrins, and hemograms. All patients were hospitalized during the study period in the University of Maryland Hospital. Twenty-four-hour specimens of urine were collected for lead determination. Three patients were hospitalized for nine days before treatment was instituted, and during this time six twenty-four-hour urinary lead determination prior to the institution of therapy. Urinary lead excretion thereafter was determined in all patients throughout the course of study. The Dithizone method with buffer extraction⁵ was used to determine urinary lead. A lumbar puncture was performed at the time of admission. Determinations of sugar, chloride, protein, and cell count were done on the spinal fluid. Hemograms, with particular attention to hemoglobin, leukocyte count, and stippling, were done throughout the study. Serum calcium, phosphorus, and total protein content were measured initially and throughout the study.

Ionizable calcium values were determined from Hastings nomogram. Electroencephalograms were obtained initially and after completion of therapy. Electrocardiograms were recorded initially, throughout, and at the end of the study.

The dosage of CaEDTA was 75mg per kilogram per day given in divided doses at six-hour intervals. Patients were maintained on the drug for a period of nine days.