“Unleaded or Leaded”: Lead Poisoning after Ingestion

Abstract

Purpose: Lead (Pb) poisoning is usually associated with childhood exposure. We describe an unusual case of abdominal pain due to Pb poisoning from herbal ingestion. Case Report: 48-year-old female with hypertension presents with crampy peri-umbilical abdominal pain and altered mental status: she admits frequent use of herbal supplements/teas, and no occupational or environmental exposure to Pb. Abdominal xray (Figure 1) and CT-Scan shows small high density areas with streak artifacts scattered along ascending colon and cecum. Lab findings reveal normocytic anemia, low haptoglobin, reticulocytosis and basophilic stippling on peripheral smear. Pb levels are noted to be greater than 60 mcg/dL along with elevated protoporphyrins levels. Pb levels 3 days later increase to 284 mcg/dL. She is then transferred for chelation therapy with IV calcium, ethylenediaminetetraacetic acid and dimercaprol. During colonoscopy multiple black multifaceted metallic fragments are extracted: Pb level then drops to 159 mcg/dL, her abdominal pain resolves and she is discharged home. Discussion: In adults, inorganic Pb is absorbed from either the lungs or the gastrointestinal tract with an absorption rate of 40% and 10% respectively. Pb interferes with heme synthesis. Anemia is frequently microcytic but can be normochromic normocytic. Pb is commonly incorporated into indian ayurvedic preparations and chinese herbal remedies. Women who reported using herbal supplements had Pb levels 10% higher than non-users, although both groups were low (<2.0 mcg/dL). Blood Pb levels were about 20% higher for those women reporting use of ayurvedic and/or traditional chinese medicine herbs, as well as St. John's wort, compared to non-users. The mainstay of treatment is removal of the source of Pb. For those who are symptomatic and/or have high blood Pb levels, chelation therapy is preferred. When Pb materials are present in the gastrointestinal tract, whole bowel irrigation, cathartics, endoscopy, or even surgery may be used to eliminate it from the gut and prevent further exposure.Figure 1: Intraluminal metallic objects on abdominal xray.