The Case
A 3-month-old breastfed male is brought to the ED with:
- 5 days of constipation
- Decreased feeding
- Weak cry
On exam:
- Afebrile
- Poor tone
- Slight drooling
- Poor gag reflex
You pause. The baby’s floppy. He’s not febrile. He’s not actively seizing. But something is clearly wrong.
Diagnosis: Infant Botulism
This is classic: a floppy, constipated infant with descending paralysis.
Pathophysiology:
- Caused by Clostridium botulinum, an obligate anaerobic, gram-positive bacillus
- Spores are ingested (often from environmental dust or food)
- Spores germinate in the infant gut → release botulinum neurotoxin
- Toxin blocks acetylcholine release at the neuromuscular junction → flaccid paralysis
Key Clinical Clues
- Constipation is often the first symptom
- Cranial nerve dysfunction: weak suck, poor gag, ptosis, expressionless face
- Descending symmetric paralysis
- Floppy tone, diminished reflexes
- Afebrile despite serious illness
PEM Pearl: A floppy, afebrile infant with constipation is botulism until proven otherwise.
Diagnosis
- Clinical diagnosis is key
- Confirm with: Toxin detection in stool
- Labs and LP are usually normal
Treatment
Human Botulism Immune Globulin (BabyBIG, BIG-IV)
- Derived from immunized plasma donors
- Available only through the California Department of Public Health (CDPH)
- 24/7 physician line: (510) 231-7600
- Website: infantbotulism.org
Yes, it’s expensive (~$45,000 per dose). But the decreased length of stay and improved outcomes make it cost-effective—and life-changing.
They Also Collect the Data
CDPH collects clinical data from every infant treated with BIG-IV in the U.S., even those later found not to have botulism.
This unique dataset has led to multiple high-quality publications on the diagnosis, treatment, and outcomes of infant botulism—and the occasional diagnostic surprise.
We’ll link a few of those studies at the end of this post for deeper reading.
Why This Matters
- Infant botulism is rare but highly treatable
- If recognized early and BIG-IV is given, prognosis is excellent
- Delay in diagnosis = prolonged ICU stay, higher risk of complications
Final Thought
It doesn’t take honey to get botulism.
In fact, most cases have no identifiable exposure.
So when the floppy baby rolls in:
- Think botulism
- Call California
- And remember that constipation may be your most important clue
Resources
Efficacy of Human Botulism Immune Globulin for the Treatment of Infant Botulism: The First 12 Years Post Licensure. J Pediatr. 2018 Feb;193:172-177. doi: 10.1016/j.jpeds.2017.10.035. Epub 2017 Dec 8. PMID: 29229452.
More Clinical Mimics of Infant Botulism. J Pediatr. 2018 Feb;193:178-182. doi: 10.1016/j.jpeds.2017.09.044. Epub 2017 Dec 8. PMID: 29229451.
Dr. Joshua Belfer, MD, is a Pediatric Emergency Medicine physician at the Children’s Hospital of Philadelphia, and is the Founder and Editor-in-Chief of HipPEMcrates. He can be reached at HipPEMcrates@gmail.com.
