A large travel-associated outbreak of iatrogenic botulism in four European countries following intragastric botulinum neurotoxin injections for weight reduction, Türkiye, February to March 2023

High risk and low prevalence diseases: Botulism

INTRODUCTION

Botulism is a serious condition that carries with it a high rate of morbidity and mortality.

OBJECTIVE

This review highlights the pearls and pitfalls of botulism, including presentation, diagnosis, and management in the emergency department (ED) based on current evidence.

DISCUSSION

Botulism is a neuromuscular disorder caused by toxin production of clostridium species bacteria and is a challenging diagnosis that mimics several other conditions. Children account for the majority of patients, with a foodborne source most common, followed by wound sources, typically from intravenous drug injection. Classically, patients with botulism develop bilateral cranial nerve palsies and symmetric, bilateral, descending paralysis. However, patients may initially present with vague symptomatology, such as weakness and dry mouth, which can make diagnosis challenging. A careful history elucidating exposures such as intravenous drug use or consumption of non-commercial canned products can help differentiate botulism from other disorders causing neuromuscular weakness. If suspected, the Centers for Disease Control should be notified to mobilize antitoxin for treatment as soon as the diagnosis is suspected even prior to confirmatory testing. Antibiotics should be avoided in these patients, as they can potentiate toxin release, unless there is a concomitant infection requiring antibiotic therapy. Patients with botulism can develop respiratory compromise requiring emergent airway management. Prolonged neuromuscular blockade from botulism will lead to a variety of symptoms that require comprehensive intensive care unit level care.

CONCLUSION

An understanding of botulism and its many potential mimics can assist emergency clinicians in diagnosing and managing this deadly disease.

The Degradation of Botulinum Neurotoxin Light Chains Using PROTACs

Botulinum neurotoxins are some of the most potent natural toxins known; they cause flaccid paralysis by inhibiting synaptic vesicle release. Some serotypes, notably serotype A and B, can cause persistent paralysis lasting for several months. Because of their potency and persistence, botulinum neurotoxins are now used to manage several clinical conditions, and there is interest in expanding their clinical applications using engineered toxins with novel substrate specificities. It will also be beneficial to engineer toxins with tunable persistence. We have investigated the potential use of small-molecule proteolysis-targeting chimeras (PROTACs) to vary the persistence of modified recombinant botulinum neurotoxins. We also describe a complementary approach that has potential relevance for botulism treatment. This second approach uses a camelid heavy chain antibody directed against botulinum neurotoxin that is modified to bind the PROTAC. These strategies provide proof of principle for the use of two different approaches to fine tune the persistence of botulinum neurotoxins by selectively targeting their catalytic light chains for proteasomal degradation.

Electrophysiological abnormalities of the neuromuscular transmission in two patients with botulism-like syndrome following Botulinum-A muscle injections

Botulinum neurotoxin serotype A (BoNT-A) has several therapeutic indications such as spasticity and dystonia. Although its use is generally considered safe, a systemic diffusion can lead to systemic complications, and a botulism-like syndrome can occur after intramuscular injections. Herein, two adult cases who developed general muscle weakness after a BoNT-A intramuscular injection are reported. Both presented with a progressive decrement on low-frequency (LF) repetitive nerve stimulation (RNS). It is suggested that a progressive decrement on LF-RNS in muscles distant from the injection site strongly supports the diagnosis of iatrogenic botulism.

Neurotoxicology: a clinical systems-based review

Neurological disease caused by toxins is widespread but under-recognised. Despite increasing public interest and a growing number of novel potential neurotoxins, diagnosis of neurotoxic disease is often delayed or missed, resulting in poorer patient outcomes. This article discusses neurotoxic syndromes using a systems-based approach, focusing on environmental and occupational agents. We do not discuss recreational drugs, pharmaceutical agents or developmental neurotoxins in detail. We aim to provide neurologists with a working understanding of the scenarios in which a clinical presentation may be due to a neurotoxin and how to approach confirmation of the diagnosis.

Intragastric Botulinum Toxin Injection and Botulism: An Alarm for Clinicians

Clostridium botulinum produces the most potent bacterial toxin, botulinum toxin A (BTXA), which has various therapeutic and cosmetic indications. Intragastric BTXA injection is a new obesity treatment method that was argued to be safe due to the inactivation of BTXA through the liver or metabolization within the gastric wall. However, a 36-year-old woman was admitted to the intensive care unit (ICU) due to developing botulism as a result of an intragastric injection of BTXA. The diplopia, headaches, ptosis, decreased muscle force, and respiratory distress two days after injection were her first chief complaints, and also, she experienced significant dysphagia, hoarse voice, thick tongue, constipation, hyposmia, and hypogeusia after two weeks. This case report highlights the necessity for physicians to have sufficient information about this method and consider possible life-threatening adverse effects including botulism.

Clinicopathological insights into an outbreak of foodborne botulism in Hamadan, Iran, in 2023: A microbiological and laboratory findings

Background and Objective

Foodborne botulism is one of the potentially fatal forms of food poisoning, usually caused by ingestion of home-canned vegetables, fruits, and dairy and fish products. This study aimed to assess the frequency of signs and symptoms in patients with botulism following the ingestion of homemade Doogh, a traditional milk-based beverage, in Hamadan, Iran in 2023. We also examined the general characteristics of the recruited patients.

Methods

During an outbreak, 21 patients were referred to the hospital because of food poisoning. All patients had a history of consumption of Doogh. After careful physical examination, all of them were hospitalized. Botulism was suspected in all patients except for the first patient.

Results

The mean age of admitted patients was 33.09 ± 18.44 years, with 23.80% being males and 76.20% females. Incubation period in our patients was 68 ± 28.48 h. Notable symptoms included diplopia (95.23%), nausea and vomiting (85.71%), blurred vision (80.95%), and dizziness (61.90%). The laboratory results were within the normal range. No deaths occurred in this patient cohort. Furthermore, botulinum spores were detected in Doogh samples collected from the outbreak, confirming the presence of Clostridium botulinum spores as a source of the outbreak.

Conclusions

This study highlights that the initial manifestations of botulism predominantly involved ophthalmologic abnormalities in most patients. Additionally, symptoms such as nausea, vomiting, and dizziness may manifest in cases of foodborne botulism. Timely diagnosis and treatment of botulism following the consumption of homemade Doogh played a crucial role in achieving positive outcomes, with no fatalities recorded in this patient cohort.

Botulism after intragastric botulinum toxin injections for weight reduction

Although-considering the risk-benefit ratio-botulinum neurotoxin A (BoNT/A) is unequivocally recommended to treat severe neurological diseases such as dystonia, this has not yet been determined for its endoscopic intragastric injection aimed at weight reduction in obesity. However, severe adverse effects of intragastric BoNT/A had not yet been reported, prompting some European countries to endorse its (off-label) use and treat patients transnationally. We here present three cases of botulism after intragastric BoNT/A injections for obesity treatment in a Turkish hospital. Patients presented with cranial nerve affection, bulbar symptoms, and descending paresis, and benefited from treatment with BoNT antitoxin and pyridostigmine. We assume that iatrogenic botulism was induced by overdosing in combination with toxin spread via the highly vascularized gastric tissue. Of note, within a few weeks, more than 80 cases of iatrogenic botulism were reported across Europe after identical intragastric BoNT/A injections. These cases demonstrate the risks of BoNT/A injections if they are not applied within the limits of evidence-based medicine. There is a need for international guidelines to define the indication and a safe dosing scheme, especially in the context of medical tourism.