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 concentration should be measured four to six hours after ingestion. With enteric-coated or extended-release preparations, absorption can be delayed, so a repeat level may be necessary.

4. Working It Up and Treating It

Start with the basics: ABCs, early IV or IO access, and aggressive treatment of shock. These children may need significant fluid resuscitation and vasoactive support.

The most useful diagnostic test is a serum iron level drawn four to six hours after ingestion. Under 350 micrograms per deciliter is associated with minimal toxicity, 350 to 500 with mild to moderate toxicity, above 500 with serious systemic toxicity, and above 1,000 with severe toxicity and increased risk of mortality. But treatment decisions should be based on the entire clinical picture, not just the iron level.

Check electrolytes, an anion gap, blood gas, lactate, liver enzymes, and coagulation studies to assess the severity of systemic toxicity.

An abdominal X-ray can be helpful because many iron tablets are radiopaque. A positive film confirms tablets are present and can help guide decontamination, but a negative X-ray does not exclude an iron ingestion.

Like all other periodic table elements, activated charcoal does not bind iron. If tablets are visible on imaging, whole bowel irrigation should be considered.

For serious toxicity, including shock, metabolic acidosis, altered mental status, or a serum iron level above 500, consider IV deferoxamine. Hypotension can occur with rapid administration, so make sure the child has adequate volume resuscitation.

Most importantly, treat the patient, not the iron level. Aggressively resuscitate shock, reassess frequently, and involve Poison Control early for any child with significant symptoms or a potentially toxic ingestion.

5. Who Goes Home, Who Gets Admitted

For disposition, start with the estimated elemental iron dose, not the total tablet or iron salt weight. Less than 20 milligrams per kilogram is generally low risk, while 40 milligrams per kilogram or more should raise concern for significant toxicity. Newer pediatric data suggest serious toxicity may occur at lower doses, but the reported dose is imperfect, so symptoms and the serum iron concentration matter more than any single cutoff.

Pay attention to what was actually ingested. Prenatal vitamins often contain substantial amounts of elemental iron, commonly around 27 to 65 milligrams per tablet, while multivitamins often contain little or no iron. A toddler can therefore reach a toxic dose with only a handful of prenatal vitamins.

An asymptomatic child more than six hours after a low-risk ingestion with a reassuring serum iron level can typically go home. Children with significant symptoms or ongoing fluid requirements should be admitted. Hemodynamic instability or the need for deferoxamine warrants ICU-level care. Discuss significant ingestions with Poison Control.

After significant toxicity, counsel families that GI strictures can develop weeks later and present with recurrent vomiting or obstruction.

6. Three Take-Homes

1. Iron poisoning is deceptive. Early vomiting and diarrhea can look like gastroenteritis, and apparent improvement during the latent phase does not mean the child is in the clear.
2. Obtain a serum iron level four to six hours post-ingestion. It’s your most useful test, but interpret it alongside the clinical picture.
3. Activated charcoal does not bind iron. Consider whole bowel irrigation when tablets are visible on imaging, and treat serious toxicity, including shock, metabolic acidosis, altered mental status, or an iron level above 500, with aggressive supportive care and deferoxamine.