Clostridium botulinum disorders associated with speech processes and verbal communication: a comprehensive and documented review

Abstract

Clostridium botulinum is an anaerobic, spore-forming bacterium which produces eight different antigenic exotoxins (A, B, C1, C2, D, E, F, and G) and among them A, B, E and F are special for humans. This toxin has heavy (H) and light (L) chains, the light chain acts on Snap-25 protein in neuromuscular junction and cause paralysis in skeletal muscles by disabling SNARE proteins and then inhibiting the release of acetylcholine, then, causing diplopia, dysarthria, dysphagia. Among all clinical signs, dysarthria is characterized by difficulty in speech which is caused by paralysis of muscles of larynx, pharynx and oral cavity which are related to phonation and then speech. Dysarthria is a sign of botulism that appears in different kinds of botulism, but especially in wound botulism. Early administration of antitoxin play a vital role in the treatment, but the efficacy of antibiotic therapy has not been completely understood, because it can either improve or worsen the situation, also supportive treatments such as mechanical ventilation, physiotherapy and gastric lavage may help to reduce the incubation period.