Infant botulism

Infant botulism (also known as infantile botulism) is a rare but serious neuroparalytic illness caused by the colonization of the infant intestinal tract by Clostridium botulinum (or rarely other botulinum toxin-producing Clostridium species), which produces botulinum neurotoxin in vivo. Unlike foodborne botulism in older individuals, infant botulism results from ingestion of bacterial spores rather than preformed toxin. The spores germinate and colonize the immature infant gut, where they produce toxin that is absorbed systemically. The toxin blocks acetylcholine release at the neuromuscular junction, leading to descending flaccid paralysis. The disease predominantly affects infants under 12 months of age, with peak incidence between 2 and 4 months. The hallmark presentation begins with constipation, followed by progressive weakness, poor feeding, weak cry, diminished suck and gag reflexes, decreased facial expression, ptosis, sluggish pupillary responses, and generalized hypotonia often described as a 'floppy baby.' In severe cases, respiratory failure may occur, requiring mechanical ventilation. Cranial nerve palsies are typically prominent. The severity ranges from mild illness with subtle hypotonia to fulminant paralysis. Sudden infant death syndrome (SIDS) has been associated with infant botulism in some cases. Treatment includes supportive care with careful attention to respiratory status, nutritional support, and monitoring in an intensive care setting. Botulism Immune Globulin Intravenous (BIG-IV, marketed as BabyBIG®) is the specific antitoxin approved for treatment of infant botulism caused by type A or type B toxin. Early administration of BIG-IV has been shown to significantly reduce hospital stay, duration of mechanical ventilation, and duration of tube feeding. Antibiotics are generally avoided as they may lyse bacteria in the gut and paradoxically increase toxin release. With appropriate supportive care and antitoxin therapy, the prognosis is generally excellent, with a case fatality rate of less than 1% in hospitalized infants. Recovery occurs as new neuromuscular junctions are formed, which may take weeks to months.

Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.

Common questions about Infant botulism