Parents bring in a 6-week-old female with a chief complaint of “listlessness.” For the previous 3 days, the patient had not been breast feeding well. Mom reports that she acts like she wants to eat but is having trouble sucking and trouble swallowing as well. Parents also state that the baby is lethargic and her muscle tone seems decreased. The patient previously could lift her head, but now cannot.

She had essentially no PO intake for 3 days. She also has not had a bowel movement in 6 days, but Mom reports that patient has been constipated for at least a month, with scant stools on an irregular basis. The baby was born at 38 weeks via normal vaginal delivery. The parents deny any rash. They live and work on a farm. She has had no medical problems since birth. There have been no recent fevers or URI symptoms. No recent travel.

Physical Exam

Vital signs are normal, and the patient is afebrile. In general the baby appears not to interact. She is breathing on her own and responds to physical stimuli. Neurologically, she has decreased tone throughout, and her eyelids exhibit ptosis. Her swallow reflex is diminished and she seems to have trouble managing her secretions. When suctioned, she has vagally stimulated bradycardia that seems to last longer than the normal low heart rate that occurs during suctioning infants. There is no associated hypotension or hypoxia at the initial presentation. Heart and lung exam is normal. Abdomen is soft.

Management

Labs including a CBC, CMP, and ABG were drawn, as well as a blood culture. The labs all returned as normal. CT of the head showed no intracranial mass or bleeding. A lumbar puncture was performed and demonstrated no white or red blood cells. CSF protein was slightly elevated. No bacteria appeared on CSF Gram stain or grew out on culture.

Neurology was consulted. The patient was treated for encephalitis in the emergency department, but the antibiotics and antiviral therapy were stopped once the cultures came back negative. The patient was admitted to the Pediatric ICU. The baby was placed on nasal BiPAP, as she began to have spontaneous desaturations into the mid 80s and bradycardic events with minimal stimulation. Infectious disease was consulted as well, and it was decided that the symptoms were consistent with botulism. Baby BIG was flown from California and administered. Within 24 hours improvement was noted. After 3 days the baby was able to restart PO feeds. She was ultimately discharged 2 weeks after admission.

Discussion

Clostridium Botulism

Botulism is a neuromuscular disorder caused by the organism Clostridium botulinum. C. botulinum is an anaerobic, Gram-positive rod that survives in soil and marine sediment by forming spores. Either the toxin is ingested, or the spores that contain the toxin are ingested. The bacteria release toxins in the gut, which are absorbed by the stomach and small intestine. They are then hematogenously disseminated. The toxin binds irreversibly to the presynaptic membranes of peripheral neuromuscular and autonomic nerve junctions, which blocks acetylcholine release. This results in weakness, flaccid paralysis (floppy baby), poor suck, constipation, and even respiratory arrest. About 145 cases of botulism are reported per year, 15% of which are food-borne and 65% infantile. The remaining 20% are wound-related.

Infantile botulism

This is caused by ingested C. botulinum spores, which colonize the large intestine and produce the toxin in the gut. The spores come from honey, improperly canned food, or home-prepared food, or in this case, from the soil. This is different from food-borne botulism, which is caused by eating foods with the preformed toxin and is usually associated with home-canned foods.

“Baby BIG”

The mechanism of action of BIG, or botulism immune globulin, is interruption of the neuromuscular blockade. The immune globulin contains antibodies that neutralize circulating toxins before they can bind to the nerves. This human-derived antitoxin can provide protection for 4 months. One dose of BIG reduces duration of hospitalization by half. It is for use in patients younger than 1 year old.

References

1. “Botulism immune globulin.” Reference.medscape.com/drug.babybig-botulism-immune-globulin-iv-999584.
2. “Botulism.” Gale Encyclopedia of Children’s Health. 2006. www.encyclopedia.com/topic/botulism.aspx.
3. “Botulism.” CDC. www.cdc.gov/ncidod/dbmd/diseaseinfo/files/botulism.PDF.

Dr. Stone is an emergency medicine resident at the Albany Medical Center in New York.