Botulism for Clinicians: Recognize It, Call for Antitoxin, Don't Wait for the Lab

Botulism is a neuroparalytic illness: a symmetric, descending, flaccid paralysis of motor and autonomic nerves that always starts with the cranial nerves. Four things to know first:

1. Diagnose it clinically, from the symptoms.
2. Expert consultation is available around the clock.
3. If consultation supports botulism, treat at once — don't wait for lab confirmation.
4. It is notifiable: report every suspected case to the state health department.

A patient with mild or early botulism (the man) and one with severe botulism (the woman). Patients may look lethargic but are fully conscious. Image from CDC's page

Signs and symptoms

Untreated, any type can progress to paralysis of the breathing muscles, arms and legs.

Telling it apart

Unlike other flaccid paralyses, botulism typically begins with prominent cranial nerve palsies, and it is:

• always descending;
• symmetric;
• without sensory loss.

It is often misdiagnosed — most often as Guillain-Barré or Miller-Fisher syndrome, myasthenia gravis, or other central nervous system disease. Routine lab results are usually unremarkable. A normal Tensilon test helps separate it from myasthenia gravis (borderline results can occur in botulism), and a normal CT or MRI helps rule out cerebrovascular accident.

Get help immediately

Suspect botulism? Call your state health department at once for consultation and, if needed, antitoxin release — use its after-hours number if necessary. If it doesn't answer:

Treatment

Antitoxin — early. Botulism Antitoxin Heptavalent and, for infants, BabyBIG don't reverse paralysis; they stop it progressing by neutralizing toxin still circulating in the blood. Given early, they can prevent worse paralysis and its complications.

Meticulous intensive care.

• Monitor breathing; ventilate when needed — in severe cases for weeks to months.
• Look after bladder and bowel, and prevent urinary tract infections, DVT and pressure ulcers.
• Treat dry eyes and dry mouth, and be ready for heavy oral secretions.

Wound botulism may also need debridement to remove the source of toxin-producing bacteria, plus antibiotics.

The patient is awake

Patients are usually fully aware. Set up a way for them to communicate, and explain procedures before doing them. Watch for anxiety and depression; consider music, massage, and family or staff reading aloud. Educate families about the illness, care and outlook, point them to support, and consider a support group if several patients are hospitalized.

Recovery and outcomes

• Recovery depends on the body growing new nerve–muscle connections, which takes weeks to months, even after antitoxin.
• Start speech, physical and occupational therapy as early as possible.
• About 5% of patients die, from respiratory failure or the effects of prolonged paralysis. Survivors may have fatigue and shortness of breath for years.

Lab confirmation

Confirmation means finding botulinum toxin in serum, stool or food, or growing a toxin-producing Clostridium (C. botulinum, C. butyricum or C. baratii) from stool or a wound. Testing runs through the state public health laboratory (CDC tests for some states) and often takes days — follow up if results haven't arrived within five days.

Reporting

Physicians must promptly report suspected cases, and laboratories confirmed cases, to the state health department, which reports confirmed cases to CDC through the National Notifiable Diseases Surveillance System. More: clinician resources for botulism.

Sources

Based on "Information for Health Professionals about Botulism" (Clinical Overview of Botulism), Centers for Disease Control and Prevention; a work of the United States government in the public domain.