A three month old male presents to the pediatric emergency department with his mother who reports patient has been constipated recently, his last bowel movement was five days ago.  She reports he has also been had decreased appetite and PO intake.  No vomiting.  No obvious pain complaints.  He appears generally weak to his mother.  His mother also reports that two weeks prior she had switched feedings from breastmilk to formula feeding.  There are no known sick contacts.  He lives in a house with is mother, father, and three year old sibling.

His vital signs are: T = 36.7, BP = 82/58, HR = 110, RR = 22, O2 saturation = 100% (room air)

His physical exam is remarkable for:


Decreased pupillary reflexes

Poor gag reflex

Dry mucous membranes

Flat anterior fontanelle

What diagnoses do you need to consider on your differential? What disease do you think this child has?

Consider GI causes (functional constipation, malrotation, Hirschprug’s disease, gastroenteritis), neurological (spinal muscular atrophy, GBS, Eaton Lambert syndrome, meningoencephalitis), cardiovascular (congential heart disease, myocarditis), ID (sepsis!), toxin exposure/ingestion, etc.

And the diagnosis is…….

Infantile intestinal botulism

Infant botulism is caused by ingestion of Clostridium botullnum spores found in either the soil or honey products. Clostridium botullnum is an anaerobic, gram-positive bacilli.  Interestingly, approximately 90% of the world’s cases of infant botulism are diagnosed in the United States – with California, Pennsylvania, and Utah having the highest incidence.

The spores produced by Clostridium botullnum germinate into bacteria that colonize the infant’s intestines and synthesize toxins A and B that bind to presynaptic acetylcholine receptors at motor nerve terminals at neuromuscular junctions.  As a result, there is inhibition of the release of acetylcholine at these junctions.

The peak incidence of infantile intestinal botulism is two to three months of age, just like the above patient. Signs and symptoms of infected infants include – impaired gag reflex, poor sucking ability, weak cry, hypotension, decreased PO intake, irritability, lethargy, constipation, and neurogenic bladder.

To treat infant botulism, first ensure that you have close monitoring of the patient’s A + B (airway and breathing) and watch for respiratory compromise/failure.  Botulinum immune globulin can also be used.  Infants will also likely need nasogastric feedings during their hospital course.

Definitive diagnosis is made via detection of the botulinum toxin + Clostridium botullnum in stool samples.

In the above case, the suspected source was thought to be through exposure to spores in soil.

Thanks to one of our PEM fellows, Kim, for this great case!

June 2024