Snapshot A 2-year-old girl is teething and chewing on objects found in the home. The parents state that for the past few days, their daughter has been fussy and at times appears lethargic and pale. They also noticed that she has been clutching her abdomen in pain and refusing to eat even her favorite foods. Laboratory testing reveals an elevated free erythrocyte protoporphyrin (FEP) level, along with the finding on peripheral blood smear seen in the image. Introduction Overview lead poisoning is caused by occupational and environmental lead exposure and can cause damage to various body systems treatment may involve chelation therapy Epidemiology prevalence estimated 1.2 million children in the US estimated 16 per 100,000 employed adults (due to occupational exposure) demographics children aged 1-5 years login to view 2 more bullets adults with occupational exposure to lead or exposure through a hobby location absorption through respiratory tract, GI tract, and skin distribution to blood, soft tissues, and bones risk factors age login to view 1 more bullet living in a house built before 1978 with chipped paint occupational exposure in lead-related industries (i.e., battery recycling, manufacturing, construction, and mining) exposure from hobbies involving lead (i.e., car repair, metal soldering, and glazed pottery making) Pathophysiology lead inhibits key enzymes in heme synthesis pathway inhibits ferrochelatase and ALA dehydratase leads to ↓ heme synthesis results in ↑ RBC protoporhyrin lead inhibits rRNA degradation causes rRNA to aggregate in RBCs login to view 1 more bullet lead causes toxicity through the generation of reactive oxygen species Presentation Symptoms typically nonspecific, result from lead toxicity irritability headache hyperactivity or lethargy anorexia various body systems affected hematological login to view 1 more bullet gastrointestinal login to view 3 more bullets renal login to view 1 more bullet CNS login to view 3 more bullets Physical exam lead lines on gingivae at base of the teeth peripheral neuropathy wrist or foot drop pallor Imaging Radiographs indications abdominal x-ray in all children with suspected ↑ blood lead levels findings lead-containing paint chips or other lead-containing objects within the GI tract lead lines on metaphyses of long bones in growing children login to view 1 more bullet Studies Serum labs blood lead level most accurate test for lead poisoning ↑ lead level (> 10 μg/dL) on venous blood sample free erythrocyte protoporphyrin (FEP) level ↑ FEP due to inhibition of enzymes involved in hemoglobin synthesis note, iron deficiency anemia may also produce an ↑ in FEP ↓ MCV and TIBC ↑ serum iron and ferritin Histology peripheral blood smear hypochromic microcytic anemia basophilic stippling of RBCs Differential Diagnosis Iron deficiency anemia key distinguishing factor ↓ serum iron and ferritin Treatment Lifestyle prevent further exposure to lead via assessment of environmental and occupational exposure modify children's behavior to decrease hand-to-mouth activity Medical chelation therapy indications login to view 1 more bullet modalities login to view 7 more bullets Complications Developmental delay in children Lead encephalopathy treatment chelation therapy