Toxicology: Iron

Iron poisoning can be deceptive. Early symptoms can look like routine gastroenteritis, children may appear to improve during a latent phase, and significant toxicity can progress to metabolic acidosis, shock, and hepatic injury. In this episode of PEM Currents, we review the recognition and management of pediatric iron toxicity, including when to obtain a serum iron level, the role of abdominal radiographs and whole bowel irrigation, indications for deferoxamine, and disposition.

Learning Objectives

After listening to this episode, learners should be able to:

1. Recognize the clinical stages of pediatric iron toxicity and identify features concerning for significant systemic toxicity.
2. Use the estimated elemental iron dose, serum iron concentration, and abdominal radiography to evaluate a child with a suspected iron ingestion.
3. Describe the emergency management of iron toxicity, including supportive care, whole bowel irrigation, indications for deferoxamine, and appropriate disposition.

References

1. Manoguerra AS, Erdman AR, Booze LL, et al. Iron ingestion: an evidence-based consensus guideline for out-of-hospital management. Clin Toxicol (Phila). 2005;43(6):553-570.
2. Halil H, Tuygun N, Polat E, Karacan CD. Minimum ingested iron cut-off triggering serious iron toxicity in children. Pediatr Int. 2019;61(5):444-448.
3. Klein-Schwartz W, Oderda GM, Gorman RL, Favin F, Rose SR. Assessment of management guidelines: acute iron ingestion. Clin Pediatr (Phila). 1990;29(6):316-321.
4. Banner W Jr, Tong TG. Iron poisoning. Pediatr Clin North Am. 1986;33(2):393-409.

Script

This is the original script for the episode, written by Drs. Robbie Daulton and Brad Sobolewski

1. Why Iron Matters

Iron is one of the most dangerous toxic ingestions we see in young children. It’s found in prenatal vitamin and iron supplements, and the small, often candy-like tablets make exploratory toddler ingestions particularly concerning. Historically, iron was a leading cause of death from unintentional pediatric drug ingestion. What makes iron especially important in the ED is that early toxicity can look just like gastroenteritis, with vomiting, diarrhea, and abdominal pain. If you’re not thinking about an ingestion, it can be easy to miss.

2. How Kids Present: The Five Stages

Iron follows a staged, sometimes deceptive, clinical course, although not every child progresses through every stage.

Stage one begins 30 minutes to six hours after ingestion with vomiting, diarrhea, abdominal pain, and sometimes GI bleeding from direct mucosal injury. This is the stage that can easily be mistaken for gastroenteritis.

Stage two, from about six to 24 hours, is the trap. GI symptoms may improve and the child may appear better, even as systemic toxicity progresses.

Stage three, typically 12 to 24 hours after ingestion, is characterized by shock and metabolic acidosis. Children may be hypotensive, tachycardic, lethargic, and poorly perfused.

Stages four and five occur later. Hepatic failure can develop over the next several days, while GI strictures and obstruction can occur weeks later.

The pattern to remember is early GI symptoms, apparent improvement, and then unexplained shock and metabolic acidosis. That should make you think about iron toxicity even if the ingestion wasn’t clear from the history.

3. Pharmacology Pearls

Iron causes toxicity in two ways. First it directly injuries the GI mucosa, causing the early vomiting, diarrhea, abdominal pain. Once absorbed, free iron overwhelms the body’s binding capacity (specifically ferritin and transferrin) and causes cellular and mitochondrial injury, contributing to metabolic acidosis, vasodilation, and shock.

Serum iron typically peaks two to six hours post-ingestion, which is why the serum iron con