Infant botulism results from ingestion of Clostridium botulinum spores, their colonization of the large intestine, and toxin production in vivo. Symptoms are initial constipation followed by neuromuscular paralysis. Diagnosis is clinical and by laboratory identification of toxin or organisms in the stool. Treatment is with support and human botulism immune globulin.
(See also Botulism, Overview of Anaerobic Bacteria, and Overview of Clostridial Infections.)
Infant botulism occurs most often in infants < 6 months old. The youngest reported patient was 2 weeks old, and the oldest was 12 months old. Unlike food-borne botulism, infant botulism is caused by ingestion of spores, not by ingestion of a preformed toxin. The source of the spores is usually unknown, but some cases have been traced to ingestion of honey, which may contain C. botulinum spores; thus, infants < 12 months old should not be fed honey.
Most cases involve type A or B toxin.
Symptoms and Signs of Infant Botulism
Constipation is present initially in 90% of cases of infant botulism and is followed by neuromuscular paralysis, beginning with the cranial nerves and proceeding to peripheral and respiratory musculature. Cranial nerve deficits typically include ptosis, extraocular muscle palsies, weak cry, poor suck, decreased gag reflex, pooling of oral secretions, poor muscle tone (floppy baby syndrome), and an expressionless face.
Severity varies from mild lethargy and slowed feeding to severe hypotonia and respiratory insufficiency.
Diagnosis of Infant Botulism
Stool tests
Initially, infant botulism should be suspected based on clinical findings. Treatment should not be delayed pending test results.
Infant botulism may be confused with sepsis, congenital muscular dystrophy, spinal muscular atrophy, hypothyroidism, and benign congenital hypotonia.
Finding C. botulinum toxin or organisms in the stool establishes the diagnosis of infant botulism.
Treatment of Infant Botulism
Human botulism immune globulin
Infants are hospitalized, and supportive care (eg, ventilatory support) is given as needed. Because the organism and toxin are excreted in the stool for weeks to months after symptom onset, appropriate contact precautions must be followed.
Treatment of infant botulism is started as soon as the diagnosis is suspected; waiting for confirmatory test results, which may take days, is dangerous.
Specific treatment of infant botulism is with human botulism immune globulin (BabyBIG), which is available from the Infant Botulism Treatment and Prevention Program (IBTPP—call 510-231-7600 or visit the IBTPP web site). This antitoxin is derived from pooled human donors who have high titers of antibodies to A and/or B toxin. The dose of human botulinum immune globulin is 50 mg/kg IV, given slowly.
The horse serum heptavalent antitoxin used in adults is not recommended for infants < 1 year of age.
Antibiotics are not given because they may lyse C. botulinum in the gut and increase toxin availability.
More Information
The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.
Infant Botulism Treatment and Prevention Program: Web site or call 510-231-7600
Centers for Disease Control and Prevention (CDC): Infant Botulism: Information for Clinicians
CDC: Clinical Guidelines for Diagnosis and Treatment of Botulism, 2021
