Medical Care
Antitoxin
On March 22, 2013, the FDA approved the first botulism antitoxin that can neutralize all 7 known botulinum nerve toxin serotypes. [33] The heptavalent antitoxin is derived from horse plasma and is the only drug available for treating botulism in patients older than 1 year, including adults. It is also the only available drug for treating infant botulism that is not caused by nerve toxin type A or B; otherwise, human-origin anti-A, anti-B botulinum antitoxin (BabyBIG) should be obtained from the California Infant Botulism Treatment and Prevention Program at +1 510-231-7600 (do not use equine antitoxin for infants). [34]
Older literature on anti-ABE trivalent antitoxin does suggest that it reduces mortality (Odds Ratio [OR], 0.22; CI 0.17-0.29) most significantly against botulism types E(OR, 0.13; CI, 0.06-0.30) and A (OR, 0.57; C, 0.39-0.84). [1, 35]
BAT® [Botulism Antitoxin Heptavalent (A, B, C, D, E, F, G) - (Equine)]. [1, 36]
See the list below:
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Ideally should be administered within 24 hours of symptom onset as the antitoxin cannot reverse existing paralysis, only toxin circulating in the blood. The greatest benefit is seen among those who receive it within 2 days of illness onset. However, regardless of time after disease onset, patients should still receive antitoxin to protect unaffected synapes from persistent circulating toxin, which is known to persist for weeks in the blood. [37]
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Consult local or state health department immediately and the 24-hour CDC botulism service to request antitoxin (+1 404-639-2206 or +1 770-488-7100)
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The standard adult dose for patients >55 kg is one vial (10-22 mL per vial) diluted 1:10 in normal saline by slow intravenous infusion (0.5-2 mL/min)
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Adverse effect frequencies (all recently observed adverse effects are nonserious) [38]
See the list of potential adverse effects:
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3% Fever
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2% Rash
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1% Chills
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1% Agitation/ anxiety
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1% Edema
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1% Elevated blood pressure
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1% Nausea
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< 1% Mild serum sickness (e.g. fever, urticarial or maculopapular rash, myalgia, arthralgia, and lymphadenopathy) may occur 10-21 days after administration
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5% Other: bronchospasm, chest pressure, diaphoresis, erythema, increased respiratory rate, “jitteriness,” leukocytosis, mild hypotension, tachycardia, urinary retention, and vomiting
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As the half-lives of the antittoxin range from 7.5-34 hours, it is plausible that exposure to a high concentration of toxin may require a second dose of BAT. If disease progression worsens after the first dose should have taken effect and suspicion remains high (ie, known outbreak setting or exposure history), a second dose can be provided within 2 weeks (to avoid devloping hypersensitivity reaction to the antitoxin). [1] However, toxin exposure of this magnitude would be a rare occurence and other diagnoses should be considered in this case.
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Pregnant women with suspected botulism should be treated with BAT just as nonpregnant patients
See the BAT® package insert here.
Antibiotics
Antibiotics have no role in the treatment of foodborne or intestinal botulism. Wound botulism may require surgical debridement and antibiotic therapy because of wound infection (Clostridium may be targeted with penicillin or metronidazole). Of note, aminoglycosides should be avoided in patietns with botulism as they may aggravate disease through inhibition of presynaptic calcium uptake, which is required for acetylcholine release. [39]
Supportive Care
It is important to remember that patients with flaccid paralysis from botulism do not have sensory or cognitive impairment from the toxin.
Rigorous and supportive care is essential in patients with botulism.
Meticulous airway management is paramount, as respiratory failure is the most important threat to survival in patients with botulism.
Patients with symptoms of botulism or known exposure should be hospitalized and closely observed.
Spirometry, pulse oximetry, vital capacity, and arterial blood gases should be evaluated sequentially.
Respiratory failure can occur with unexpected rapidity.
Extrapolating from Guillain-Barré syndrome, intubation and mechanical ventilation should be strongly considered when the vital capacity is less than 20 mL/kg, especially when paralysis is progressing rapidly and hypoxemia with hypercarbia is present. [40]
Many patients require intubation and ventilatory support for a few days to months.
Tracheostomy may prove necessary to manage secretions.
Patients with bowel sounds are administered cathartics and enemas to remove unabsorbed botulinum toxin from the intestine.
Magnesium salts, citrate, and sulfate should not be administered because magnesium can potentiate the toxin-induced neuromuscular blockade.
Stress ulcer prophylaxis is also a standard component of intensive care management.
If an ileus is present, nasogastric suction and intravenous hyperalimentation are very helpful supportive measures. If no ileus is present, tube feeding can be used for nutritional supplementation.
A Foley catheter is often used to treat bladder incontinence. This must be monitored conscientiously and changed regularly.
Measures to reduce the risk of nosocomial infections include the following:
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Close observation for hospital-acquired infections, especially pneumonia (particularly aspiration pneumonia), is necessary, as is precaution to prevent aspiration. Aggressive pulmonary toilet with clearance of secretions, ventilatory support, and incentive spirometry are typically used.
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Close observation for urinary tract infection is essential. Foley catheters should be changed on a regular basis.
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Meticulous skin care is required to prevent decubital ulcers and skin breakdown.
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Careful attention to peripheral and central intravenous catheters with regular site rotation to reduce the risks of thrombophlebitis, cellulitis, and line infections should be part of the supportive care.
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Deep venous thrombosis (DVT) prophylaxis is also a standard component of intensive care management.
Surgical Care
Wound botulism requires incision and thorough debridement of the infected wound, antitoxin therapy, and antibiotics should be provided as clinically indicated.
Consultations
A nutritionist should be consulted for hyperalimentation and tube-feeding recommendations and monitoring.
Physical and occupational therapists are needed to work on range-of-motion exercises and assisted ambulation, as tolerated.
A psychiatrist and/or a psychologist is recommended for counseling, as needed; patients with prolonged hospitalization, slow recovery, and complications from the disease or from extended hospitalization are at increased risk for depression.
Pastoral care is recommended, as needed.
Physical medicine and rehabilitation specialists may be helpful in coordinating long-term rehabilitation planning once sustained recovery has begun.
Diet
Nasogastric suction and intravenous hyperalimentation are important when an ileus is present. If no ileus is present or when the ileus resolves, tube feeding can be used for nutritional supplementation.
Oral intake should be reinstituted gradually under the following conditions:
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Respiratory status is stable without mechanical ventilation.
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Swallowing safety has been assessed and confirmed with a swallowing study, as appropriate.
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Ileus has resolved.
