Health Professional Advisory

This content was archived on June 24, 2013.

Colonization botulism in adult patients with Crohn's disease

Background

Botulism is a rare disease caused by a toxin produced by the spore-forming bacterium Clostridium botulinum. This pathogen occurs naturally in the environment and can be found in soil, water, animals, contaminated food and agricultural products. The toxin produced by C. botulinum is one of the most potent natural toxins known and can affect humans, animals and even fish.

Recently, three cases of colonization botulism were reported in Ontario. Two cases were reported in November 2006 and a third case was reported in February 2007. All three patients have Crohn's disease. One of the cases has been linked with the consumption of peanut butter.

There are four categories of human botulism, namely foodborne, infant, wound and adult colonization. The most common form of botulism in Canada is food poisoning which results in an intoxication that follows the consumption of food containing pre-formed botulinum neurotoxin. Depending on the toxic dose, the incubation period may vary from 12 to 72 hours. The foods most frequently involved with food-borne botulism are home-prepared items such as cured meats, canned vegetables, fermented fish and marine mammal products.

Botulism has been misdiagnosed as myasthenia gravis, stroke or Guillain-Barré syndrome in certain instances. Suspected drug and alcohol abuse may occasionally prolong the time for a diagnosis to be made.

In this advisory, however, it is colonization botulism which is of immediate concern.

Colonization Botulism in Adults

Colonization botulism involves eating a food that contains spores of C. botulinum. The form of botulism known as adult colonization botulism is extremely rare. Approximately 10 cases have been documented worldwide between 1973 and 2007.

Colonization botulism has only been reported in individuals with predisposing anatomical or physiological abnormalities of the gastrointestinal system. In the case of colonization botulism, the patient eats a food containing the spores, the spores germinate, the organism colonizes the patient's intestine, and toxin is released in the patient causing illness.

The disease resembles infant botulism in its pathogenesis and clinical status. However, in the case of colonization botulism, other risk factors appear to be necessary in order for infection to occur. The most common risk factor identified to date appears to be Crohn's disease.

In late 2006 and early 2007, 3 patients in Ontario were confirmed as having colonization botulism. Testing of the foods found in the home of one of the patients identified a small number of C. botulinum spores in an open jar of peanut butter. In this case, spores found in the peanut butter matched the toxin type affecting the patient. This is the first documented report anywhere in the world of a link between a food and colonization botulism. So far, a source of infection has not been found in the other two cases.

Botulism, including colonization botulism, should be clinically considered when patients present symptoms that may be suggestive of any of the conditions presented below or any other unusual neurological symptoms. The first signs of botulism may include vomiting, diarrhea, nausea, fatigue and muscular weakness, but these initial symptoms may be altogether absent. Invariably, all persons with botulism develop cranial nerve palsies that may include ptosis, fixed and dilated pupils, blurred vision, diplopia, dysphagia and dysphonia, that may be followed by descending symmetrical flaccid paralysis. The muscles controlling the limbs and respiration become progressively paralyzed. If not treated, death from respiratory failure may occur within 3 to 5 days. Treatment consists mainly of intensive symptomatic care, including respiratory support. Antitoxin against botulinum toxin types A, B, and E should be immediately administered to neutralize the circulating toxin. However, the success of the antitoxin treatment is strongly dependent on the time of administration. Antitoxin will prevent progression of paralysis by neutralizing circulating free toxin, but will not reverse paralysis already present.

Recommendations:

• Colonization botulism should be clinically considered when patients present with the above described symptoms, and there is no clear foodborne or wound source.
• Physicians should be aware that patients with Crohn's disease may be at greater risk of developing colonization botulism.
• Adult colonization botulism appears to be associated with anatomical or physiological abnormalities of the gastrointestinal tract. In addition to Crohn's disease, the syndrome has occurred in two patients with Meckel's diverticulum and two individuals who had had a vagotomy. A thorough history should seek relevant information from all persons with suspected botulism.