botulism

Introduction

botulism is a potentially fatal condition caused by neurotoxic Clostridial toxins produced by Clostridium species, such as C. butyricum, C. baratii, and C. sporogenes

these neurotoxins are categorized into eight serotypes ranging from A to H.
Serotypes A, B, E, and F commonly cause human botulism
each serotype is further divided into subtypes or mosaic forms.
each serotype can cleave a particular amino acid bond in synaptic synaptosomal-associated protein (SNAP-25), syntaxin, and vesicle-associated membrane protein (VAMP). These are essential components of the soluble N-ethylmaleimide-sensitive fusion protein (NSF) attachment receptor (SNARE) complex.
SNARE-complex formation is crucial for the fusion of neurotransmitter-loaded vesicles with the synaptic membrane. Thus, cleavage of SNARE-complex proteins by BoNT stops the release of neurotransmitters, ultimately paralyzing the innervated muscle

can be caused by contaminated food
infants are particularly at risk when bacterial colonization in the infant’s intestine occurs and toxin release
can occur through wound infection or IM injections into the gluteal region
iatrogenic botulinum toxin (Botox)
- in 2023, a number of patients traveling to Turkey developed botulism after off-label use of intragastric botulinum neurotoxin injections (IBNI) during a gastroscopic procedure for weight loss causing a small outbreak in Europe ¹⁾

descending paralysis
- starts with blurred vision, ptosis, dysarthria, diplopia, and dysphagia
- then respiratory muscles are affected
- then limb muscles

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