Efficacy and toxicity of D-penicillamine in low-level lead poisoning.

In a retrospective cohort study we reviewed our experience using D-penicillamine in children with low-level lead poisoning (whole blood lead levels 25 to 40 micrograms/dL) to determine its efficacy and the incidence of side effects. Two groups were compared: treated subjects (n = 84) were treated with penicillamine at a mean daily dose of 27.5 mg/kg; control subjects (n = 37) received no chelation therapy. Over a prechelation observation period of 60 days, lead levels (PbB) did not change in either group. With a mean period of 76 days of D-penicillamine therapy, PbB fell in treated patients by 33% (P less than 0.001). In 64 patients (76%), PbB was reduced to a currently acceptable range (less than or equal to 25 micrograms/dL). There were eight treatment failures (10%). In control subjects, mean PbB did not change significantly over 119 days of observation. Fourteen control subjects eventually required conventional chelation with calcium disodium ethylene-diaminetetraacetic acid, and 17 were lost to follow-up. Use of D-penicillamine was associated with an adverse reaction in 28 cases (33%); transient leukopenia occurred in eight, rash in seven, transient platelet count depression in seven, enuresis in three, and abdominal pain in two. Treatment was terminated prematurely in eight cases (10%) because of an adverse reaction. We conclude that D-penicillamine is effective therapy for selected children with low-level plumbism, but adverse effects can complicate or prevent its use in some patients.