Botulinum Toxin - Treatment of Botulinum Poisoning

Treatment of Botulinum Poisoning

If the symptoms of botulism are diagnosed early, an equine antitoxin, use of enemas, and extracorporeal removal of the gut contents can be used to treat the food-borne illness. Wound infections can be treated surgically. Information regarding methods of safe canning, and public education about the disease are methods of prevention. Tests to detect botulism include a brain scan, a nerve conduction test, and a tensilon test for myasthenia gravis to differentiate botulism from other diseases that manifest in the same way. Electromyography can be used to differentiate myasthenia gravis and Guillain-Barré syndrome, diseases that botulism often mimics. Toxicity testing of serum specimens, wound tissue cultures, and toxicity testing, and stool specimen cultures are the best methods for identifying botulism. Laboratory tests of the patient's serum or stool, which are then injected into mice, are also indicative of botulism. The faster way to detect botulinum toxin in people, though, is using the mass spectrometry technology, because it reduces testing time to three or four hours and at the same time it can identify the seven types of the toxin.

The case fatality rate for botulinum poisoning between 1950 and 1996 was 15.5%, down from about 60% over the previous 50 years. Death is generally secondary to respiratory failure due to paralysis of the respiratory muscles, so treatment consists of antitoxin administration and artificial ventilation until the neurotoxins are excreted or metabolised. If initiated on time, these treatments are quite effective, although antisera can not affect BoNT polypeptides that have already entered cells. Occasionally, functional recovery may take several weeks to months or more.

Two primary botulinum antitoxins are available for treatment of botulism.

• Trivalent (A,B,E) botulinum antitoxin is derived from equine sources using whole antibodies (Fab and Fc portions). This antitoxin is available from the local health department via the CDC in the USA.

• The second antitoxin is Heptavalent (A,B,C,D,E,F,G) botulinum antitoxin, which is derived from "despeciated" equine IgG antibodies, which have had the Fc portion cleaved off, leaving the F(ab')2 portions. This less immunogenic antitoxin is effective against all known strains of botulism where not contraindicated, and is available from the United States Army. On June 1, 2006, the US Department of Health and Human Services awarded a $363 million contract with Cangene Corporation for 200,000 doses of heptavalent botulinum antitoxin over five years for delivery into the Strategic National Stockpile beginning in 2007.