Food-borne botulism in the United Kingdom

Pathogenicity and virulence of Clostridium botulinum

Clostridium botulinum, a polyphyletic Gram-positive taxon of bacteria, is classified purely by their ability to produce botulinum neurotoxin (BoNT). BoNT is the primary virulence factor and the causative agent of botulism. A potentially fatal disease, botulism is classically characterized by a symmetrical descending flaccid paralysis, which is left untreated can lead to respiratory failure and death. Botulism cases are classified into three main forms dependent on the nature of intoxication; foodborne, wound and infant. The BoNT, regarded as the most potent biological substance known, is a zinc metalloprotease that specifically cleaves SNARE proteins at neuromuscular junctions, preventing exocytosis of neurotransmitters, leading to muscle paralysis. The BoNT is now used to treat numerous medical conditions caused by overactive or spastic muscles and is extensively used in the cosmetic industry due to its high specificity and the exceedingly small doses needed to exert long-lasting pharmacological effects. Additionally, the ability to form endospores is critical to the pathogenicity of the bacteria. Disease transmission is often facilitated via the metabolically dormant spores that are highly resistant to environment stresses, allowing persistence in the environment in unfavourable conditions. Infant and wound botulism infections are initiated upon germination of the spores into neurotoxin producing vegetative cells, whereas foodborne botulism is attributed to ingestion of preformed BoNT. C. botulinum is a saprophytic bacterium, thought to have evolved its potent neurotoxin to establish a source of nutrients by killing its host.

Clinical Predictive Values in Botulism: A 10-year Survey

Background

Botulism occurs periodically or in outbreaks in Iran. Botulism is lethal and accordingly a considerable issue in environmental health, although it is uncommon. This study was performed to evaluate the potential predictive factors in foodborne botulism in a 10-year span.

Materials and methods

All medical records from patients with foodborne botulism admitted to Imam Reza Hospital in 10 years (2005-2015) were analyzed retrospectively.

Results

61 cases were included (38 men, mean age ± SD 28.93 ± 19.14 years). All cases were treated with antitoxin. 6.6% of cases died. Canned beans were correlated with the admission to intensive care unit (ICU), and also, it increased the length of ICU stay significantly (P = 0.007 and 0.023, respectively). The incidence of dizziness and diplopia significantly induced excess demands for higher doses of antitoxin (P = 0.038 and 0.023, respectively). Risk of dysphagia was remarkably higher in cases with ptosis (P = 0.039, odds ratio: 3). While in this study, time elapsed between the onset of clinical manifestations and antitoxin administration was correlated with the occurrence of dysphagia, constipation, and blurred vision, and early treatment did not improve the outcomes. Multiple analysis of potential variables by a logistic regression model disclosed that the independent significant factors affecting mortality were the need for mechanical ventilation (P = 0.000), dyspnea (P = 0.044), general weakness (P = 0.044), and lack of consciousness (P = 0.008) at the time of admission.

Conclusions

Taking clinical signs and symptoms into account upon patient arrival is important and, of course, is a key to further management in the emergency setting.

How to cite this article

Saeidi S, Dadpour B, Jarahi L, Ghamsari AA, Nooghabi MN. Clinical Predictive Values in Botulism: A 10-year Survey. Indian J Crit Care Med 2021;25(4):411-415.

Foodborne Botulism in Ukraine from 1955 to 2018

We aim to identify possible biological, social, and economic factors that could influence the prevalence of foodborne botulism (FB). The objective of this article is to assess epidemiological peculiarities of FB in Ukraine from 1955 to 2018 using national epidemiological surveillance data. This article presents an epidemiological descriptive population-based study of the epidemiology of FB using correlation analysis. From 1955 to 2018, 8614 cases of botulism were recorded in Ukraine causing 659 deaths. The distribution of types of botulism toxins is represented by type A (7.97%), B (59.64%), suspected as C (0.56%), E (25.47%), others (5.33%), and unidentified (1.04%). From 1990 to 2015, the rate correlation between Human Development Index (HDI) and incidence of botulism was −0.75 ± 0.20. Homemade canned meat and fish continue to be the leading causes of botulism in Ukraine. Cases related to commercial food were rare or absent, but in recent years (2017–2018), their percentage has increased to 32.56%. The HDI and botulism have an inverse mathematical correlation and predictable logical relationship: with an HDI increase, the incidence of FB decreased. In general, food botulism in Ukraine is related to traditional socioeconomic factors related to cultural food habits. In the face of declining living standards and uncertainty that food products will be physically or economically available, homemade preservation increases. Home food preservation is a major cause of botulism in Ukraine. The elimination of FB is possible in Ukraine only with the complete cessation of home canning and state control over the manufacture and sale of commercial canned products.

Diversity of the Genomes and Neurotoxins of Strains of Clostridium botulinum Group I and Clostridium sporogenes Associated with Foodborne, Infant and Wound Botulism

Clostridium botulinum Group I and Clostridium sporogenes are closely related bacteria responsible for foodborne, infant and wound botulism. A comparative genomic study with 556 highly diverse strains of C. botulinum Group I and C. sporogenes (including 417 newly sequenced strains) has been carried out to characterise the genetic diversity and spread of these bacteria and their neurotoxin genes. Core genome single-nucleotide polymorphism (SNP) analysis revealed two major lineages; C. botulinum Group I (most strains possessed botulinum neurotoxin gene(s) of types A, B and/or F) and C. sporogenes (some strains possessed a type B botulinum neurotoxin gene). Both lineages contained strains responsible for foodborne, infant and wound botulism. A new C. sporogenes cluster was identified that included five strains with a gene encoding botulinum neurotoxin sub-type B1. There was significant evidence of horizontal transfer of botulinum neurotoxin genes between distantly related bacteria. Population structure/diversity have been characterised, and novel associations discovered between whole genome lineage, botulinum neurotoxin sub-type variant, epidemiological links to foodborne, infant and wound botulism, and geographic origin. The impact of genomic and physiological variability on the botulism risk has been assessed. The genome sequences are a valuable resource for future research (e.g., pathogen biology, evolution of C. botulinum and its neurotoxin genes, improved pathogen detection and discrimination), and support enhanced risk assessments and the prevention of botulism.

Assessment of the risk of botulism from chilled, vacuum/modified atmosphere packed fresh beef, lamb and pork held at 3 °C-8 °C

The safety of current UK industry practice (including shelf-life) for chilled, vacuum/modified atmosphere-packed fresh red meat (beef, lamb and pork) held at 3°C-8°C has been evaluated with respect to non-proteolytic Clostridium botulinum. UK industry typically applies a retail pack shelf-life at 3°C-8°C to 13 days for fresh red meat, with a maximum of 23 days for beef, 27 days for lamb, and 18 days for pork. An exposure assessment established that current commercial practice for fresh red meat provided strong protection with more than 10¹⁰ person servings marketed in the UK without association with foodborne botulism. A challenge test demonstrated that spores of non-proteolytic C. botulinum inoculated on chilled vacuum-packed fresh red meat did not lead to detectable neurotoxin at day 50 for beef, day 35 for lamb, or day 25 for pork (i.e. <40 pg type B toxin and type E toxin g^-1 of meat). The products were visually spoiled many days before these end points. The exposure assessment and challenge test demonstrated the safety of current UK industry practices for the shelf-life of fresh, vacuum-packed beef, lamb and pork held at 3°C-8°C with respect to C. botulinum, and that botulinum neurotoxin was not detected within their organoleptic shelf-life.

Pan-Genomic Analysis of Clostridium botulinum Group II (Non-Proteolytic C. botulinum) Associated with Foodborne Botulism and Isolated from the Environment

The neurotoxin formed by Clostridium botulinum Group II is a major cause of foodborne botulism, a deadly intoxication. This study aims to understand the genetic diversity and spread of C. botulinum Group II strains and their neurotoxin genes. A comparative genomic study has been conducted with 208 highly diverse C. botulinum Group II strains (180 newly sequenced strains isolated from 16 countries over 80 years, 28 sequences from Genbank). Strains possessed a single type B, E, or F neurotoxin gene or were closely related strains with no neurotoxin gene. Botulinum neurotoxin subtype variants (including novel variants) with a unique amino acid sequence were identified. Core genome single-nucleotide polymorphism (SNP) analysis identified two major lineages-one with type E strains, and the second dominated by subtype B4 strains with subtype F6 strains. This study revealed novel details of population structure/diversity and established relationships between whole-genome lineage, botulinum neurotoxin subtype variant, association with foodborne botulism, epidemiology, and geographical source. Additionally, the genome sequences represent a valuable resource for the research community (e.g., understanding evolution of C. botulinum and its neurotoxin genes, dissecting key aspects of C. botulinum Group II biology). This may contribute to improved risk assessments and the prevention of foodborne botulism.

Medical treatment for botulism

BACKGROUND

Botulism is an acute paralytic illness caused by a neurotoxin produced by Clostridium botulinum. Supportive care, including intensive care, is key, but the role of other medical treatments is unclear. This is an update of a review first published in 2011.

OBJECTIVES

To assess the effects of medical treatments on mortality, duration of hospitalization, mechanical ventilation, tube or parenteral feeding, and risk of adverse events in botulism.

SEARCH METHODS

We searched the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, and Embase on 23 January 2018. We reviewed bibliographies and contacted authors and experts. We searched two clinical trials registers, WHO ICTRP and clinicaltrials.gov, on 21 February 2019.

SELECTION CRITERIA

Randomized controlled trials (RCTs) and quasi-RCTs examining the medical treatment of any of the four major types of botulism (infant intestinal botulism, food-borne botulism, wound botulism, and adult intestinal toxemia). Potential medical treatments included equine serum trivalent botulism antitoxin, human-derived botulinum immune globulin intravenous (BIG-IV), plasma exchange, 3,4-diaminopyridine, and guanidine.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology.Our primary outcome was in-hospital death from any cause occurring within four weeks from randomization or the beginning of treatment. Secondary outcomes were death from any cause occurring within 12 weeks, duration of hospitalization, duration of mechanical ventilation, duration of tube or parenteral feeding, and proportion of participants with adverse events or complications of treatment.

MAIN RESULTS

A single RCT met the inclusion criteria. Our 2018 search update identified no additional trials. The included trial evaluated BIG-IV for the treatment of infant botulism and included 59 treatment participants and 63 control participants. The control group received a control immune globulin that did not have an effect on botulinum toxin. Participants were followed during the length of their hospitalization to measure the outcomes of interest. There was some violation of intention-to-treat principles, and possibly some between-treatment group imbalances among participants admitted to the intensive care unit and mechanically ventilated, but otherwise the risk of bias was low. There were no deaths in either group, making any treatment effect on mortality inestimable. There was a benefit in the treatment group on mean duration of hospitalization (BIG-IV: 2.60 weeks, 95% confidence interval (CI) 1.95 to 3.25; control: 5.70 weeks, 95% CI 4.40 to 7.00; mean difference (MD) -3.10 weeks, 95% CI -4.52 to -1.68; moderate-certainty evidence); mechanical ventilation (BIG-IV: 1.80 weeks, 95% CI 1.20 to 2.40; control: 4.40 weeks, 95% CI 3.00 to 5.80; MD -2.60 weeks, 95% CI -4.06 to -1.14; low-certainty evidence); and tube or parenteral feeding (BIG-IV: 3.60 weeks, 95% CI 1.70 to 5.50; control: 10.00 weeks, 95% CI 6.85 to 13.15; MD -6.40 weeks, 95% CI -10.00 to -2.80; moderate-certainty evidence), but not on proportion of participants with adverse events or complications (BIG-IV: 63.08%; control: 68.75%; risk ratio 0.92, 95% CI 0.72 to 1.18; absolute risk reduction 0.06, 95% CI 0.22 to -0.11; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

We found low- and moderate-certainty evidence supporting the use of BIG-IV in infant intestinal botulism. A single RCT demonstrated that BIG-IV probably decreases the duration of hospitalization; may decrease the duration of mechanical ventilation; and probably decreases the duration of tube or parenteral feeding. Adverse events were probably no more frequent with immune globulin than with placebo. Our search did not reveal any evidence examining the use of other medical treatments including serum trivalent botulism antitoxin.

Development of immunodetection system for botulinum neurotoxin serotype E

Background & objectives

Botulism, a potentially fatal paralytic illness, is caused by the botulinum neurotoxins (BoNTs) secreted by Clostridium botulinum. It is an obligate anaerobic, Gram-positive, spore-forming bacterium. BoNTs are classified into seven serotypes based on the serological properties. Among these seven serotypes, A, B, E and, rarely, F are responsible for human botulism. The present study was undertaken to develop an enzyme-linked immunosorbent assay (ELISA)-based detection system for the detection of BoNT/E.

Methods

The synthetic gene coding the light chain of BoNT serotype E (BoNT/E LC) was constructed using the polymerase chain reaction primer overlapping method, cloned into pQE30UA vector and then transformed into Escherichia coli M15 host cells. Recombinant protein expression was optimized using different concentrations of isopropyl-β-D-1-thiogalactopyranoside (IPTG), different temperature and the rBoNT/E LC protein was purified in native conditions using affinity column chromatography. The purified recombinant protein was checked by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and further confirmed by western blot and matrix-assisted laser desorption ionization-tandem time-of-flight (MALDI-TOF). Polyclonal antibodies were generated against rBoNT/E LC using Freund's adjuvant in BALB/c mice and rabbit. Sandwich ELISA was optimized for the detection of rBoNT/E LC and native crude BoNT/E, and food matrix interference was tested. The developed antibodies were further evaluated for their specificity/cross-reactivity with BoNT serotypes and other bacterial toxins.

Results

BoNT/E LC was successfully cloned, and the maximum expression was achieved in 16 h of post-induction using 0.5 mM IPTG concentration at 25°C. Polyclonal antibodies were generated in BALB/c mice and rabbit and the antibody titre was raised up to 128,000 after the 2^nd booster dose. The developed polyclonal antibodies were highly specific and sensitive with a detection limit about 50 ng/ml for rBoNT/E LC and 2.5×10^[3] MLD₅₀ of native crude BoNT/E at a dilution of 1:3000 of mouse (capturing) and rabbit (revealing) antibodies. Further, different liquid, semisolid and solid food matrices were tested, and rBoNT/E LC was detected in almost all food samples, but different levels of interference were detected in different food matrices.

Interpretation & conclusions

There is no immune detection system available commercially in India to detect botulism. The developed system might be useful for the detection of botulinum toxin in food and clinical samples. Further work is in progress.

Retrospective survey to evaluate the safety and efficacy of Japanese botulinum antitoxin therapy in Japan

Japanese botulinum antitoxins have been used for more than 50 years; however, their safety and therapeutic efficacy are not clear. In order to analyze the available data on botulinum antitoxin therapy in Japan, we surveyed published reports about botulism cases in which botulinum antitoxins were used, and retrospectively analyzed the safety and efficacy of the therapy. A total of 134 patients administered botulinum antitoxins were identified from published reports. Two cases of side effects (1.5%) were detected after antitoxin administration, both not fatal. The fatality rate was 9.4%, and more than 70% of the patients showed improvement in their symptoms and better clinical conditions than those not treated with antitoxins. These data suggest that the therapy with Japanese antitoxins is safe and highly effective.

Three classes of plasmid (47-63 kb) carry the type B neurotoxin gene cluster of group II Clostridium botulinum

Pulsed-field gel electrophoresis and DNA sequence analysis of 26 strains of Group II (nonproteolytic) Clostridium botulinum type B4 showed that 23 strains carried their neurotoxin gene cluster on a 47–63 kb plasmid (three strains lacked any hybridization signal for the neurotoxin gene, presumably having lost their plasmid). Unexpectedly, no neurotoxin genes were found on the chromosome. This apparent constraint on neurotoxin gene transfer to the chromosome stands in marked contrast to Group I C. botulinum, in which neurotoxin gene clusters are routinely found in both locations. The three main classes of type B4 plasmid identified in this study shared different regions of homology, but were unrelated to any Group I or Group III plasmid. An important evolutionary aspect firmly links plasmid class to geographical origin, with one class apparently dominant in marine environments, whereas a second class is dominant in European terrestrial environments. A third class of plasmid is a hybrid between the other two other classes, providing evidence for contact between these seemingly geographically separated populations. Mobility via conjugation has been previously demonstrated for the type B4 plasmid of strain Eklund 17B, and similar genes associated with conjugation are present in all type B4 plasmids now described. A plasmid toxin–antitoxin system pemI gene located close to the neurotoxin gene cluster and conserved in each type B4 plasmid class may be important in understanding the mechanism which regulates this unique and unexpected bias toward plasmid-borne neurotoxin genes in Group II C. botulinum type B4.

Two-family outbreak of botulism associated with the consumption of smoked ribs in Sichuan Province, China

BACKGROUND

On September 22, 2013, two patients from Sichuan Province, China presented with symptoms of food-borne botulism, a rare but fatal illness caused by the consumption of foods containing Clostridium botulinum neurotoxins.

METHODS

Investigators reviewed the medical charts and food consumption histories, and interviewed patients and family members. Food samples and clinical specimens were tested for botulinum toxin and neurotoxin-producing Clostridium species by standard methods.

RESULTS

The first two index cases presented with cranial neuropathies and flaccid paralysis, and required mechanical ventilation. There were 12 confirmed outbreak-associated cases. Botulinum toxin type A was identified in the smoked ribs, and all of the patients had consumed the smoked ribs from the same local restaurant. The smoked ribs contained no added salt, sugar, or preservative. Botulinum toxin production likely resulted from the cold-smoking preparation method and inappropriate refrigeration.

CONCLUSIONS

Smoked ribs produced by a local restaurant, contaminated with type A botulism, was the contributor to this outbreak. The supervision of food safety should be strengthened to prevent future outbreaks in China.

Medical treatment for botulism

BACKGROUND

Botulism is an acute paralytic illness caused by a neurotoxin produced by Clostridium botulinum. Supportive care, including intensive care, is key but the role of other medical treatments is unclear. This is an update of a review first published in 2011.

OBJECTIVES

To assess the effects of medical treatments on mortality, duration of hospitalization, mechanical ventilation, tube or parenteral feeding and risk of adverse events in botulism.

SEARCH METHODS

On 30 March 2013, we searched the Cochrane Neuromuscular Disease Group Specialized Register (30 March 2013), CENTRAL (2013, Issue 3) in The Cochrane Library, MEDLINE (January 1966 to March 2013) and EMBASE (January 1980 to March 2013). We reviewed bibliographies and contacted authors and experts.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials examining the medical treatment of any of the four major types of botulism (infant intestinal botulism, food-borne botulism, wound botulism and adult intestinal toxemia). Potential medical treatments included equine serum trivalent botulism antitoxin, human-derived botulinum immune globulin, plasma exchange, 3,4-diaminopyridine and guanidine.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies, assessed risk of bias and extracted data onto data extraction forms.Our primary outcome was in-hospital death from any cause occurring within four weeks. Secondary outcomes were death occurring within 12 weeks, duration of hospitalization, mechanical ventilation, tube or parenteral feeding and risk of adverse events.

MAIN RESULTS

A single randomized controlled trial met the inclusion criteria. We found no additional trials when we updated the searches in 2013. This trial evaluated human-derived botulinum immune globulin (BIG) for the treatment of infant botulism and included 59 treatment participants as well as 63 control participants. The control group received a control immune globulin which did not have an effect on botulinum toxin. In this trial there was some violation of intention-to-treat principles, and possibly some between-treatment group imbalances among those participants admitted to the intensive care unit (ICU) and mechanically ventilated, but overall we judged the risk of bias to be low. There were no deaths in either group, making any treatment effect on mortality inestimable. There was a significant benefit in the treatment group on mean duration of hospitalization (BIG: 2.60 weeks, 95% CI 1.95 to 3.25; control: 5.70 weeks, 95% CI 4.40 to 7.00; mean difference (MD) 3.10 weeks, 95% CI 1.68 to 4.52), mechanical ventilation (BIG: 1.80 weeks, 95% CI 1.20 to 2.40; control: 4.40 weeks, 95% CI 3.00 to 5.80; MD 2.60 weeks, 95% CI 1.14 to 4.06), and tube or parenteral feeding (BIG: 3.60 weeks, 95% CI 1.70 to 5.50; control: 10.00 weeks, 95% CI 6.85 to 13.15; MD 6.40 weeks, 95% CI 2.80 to 10.00) but not on risk of adverse events or complications (BIG: 63.08%; control: 68.75%; risk ratio 0.92, 95% CI 0.72 to 1.18; absolute risk reduction 0.06, 95% CI 0.22 to -0.11).

AUTHORS' CONCLUSIONS

There is evidence supporting the use of human-derived botulinum immune globulin (BIG) in infant intestinal botulism. A single randomized controlled trial demonstrated significant decreases in the duration of hospitalization, mechanical ventilation and tube or parenteral feeding with BIG treatment. This evidence was of moderate quality for effects on duration of mechanical ventilation but was otherwise of high quality. Our search did not reveal any evidence examining the use of other medical treatments including serum trivalent botulism antitoxin.

Use of a new functional dual coating (FDC) assay to measure low toxin levels in serum and food samples following an outbreak of human botulism

Clostridium botulinum type A toxin is the most prevalent cause of naturally occurring outbreaks of human botulism in the world. The active dichain neurotoxin molecule is composed of a heavy chain (H-chain) of ~100 kDa with the carboxy-terminal end consisting of a receptor-binding (HC) domain, while the amino-terminal (HN) domain is linked by a critical disulfide bond to a light chain (L-chain) of ~50 kDa. Although the mouse bioassay (MBA) is traditionally used to confirm the presence of toxin in serum or food, its sensitivity is insufficient to detect low toxin levels in approximately 30 to 60 % of botulism patients. A novel FDC (functional dual coating) microtitre plate immuno-biochemical assay, which quantifies botulinum toxicity by measuring the HC domain linked with L-chain endopeptidase activity, was modified to allow human serum (lysed or unlysed) to be tested without interference from the matrix, with toxin detection down to 0.03 mouse LD50 per ml serum or 0.13 pg ml–1 using just 100 µl of clinical samples. The assay was specific for type A toxin and could additionally be applied to whole blood and food samples. Low levels of 1 to 2 mouse LD50 per ml serum of type A toxin were quantified for the first time using the modified FDC assay in two severely intoxicated UK patients who required mechanical ventilation and antitoxin. Toxin levels in recovered food sample extracts were also detected and one MBA-negative sample was found to contain 0.32 LD50 per ml extract. The FDC assay provides a real alternative for public health laboratories to unambiguously confirm all cases of type A botulism and, due to its sensitivity, a promising new tool in toxin pharmacokinetic studies.

Food-borne botulism: still actual topic

Even though since the mid-1990s the number of food-borne botulism cases has systematically decreased and it now occurs in Poland relatively rarely, it is still a real epidemiological problem. There are about 30 cases of botulism in Poland a year, which ranks Poland the first among the European Union. In most cases the symptomatology of botulism is typical, however it does not always fully coincide with the one described in medical manuals which emphasise the dramatic clinical course of botulism with its frequent fatal consequences. Diagnosis of botulism may be difficult because of its rare prevalence and a variable clinical course, especially in old patients. Authors of this paper describe two cases of botulism and diagnostic problems associated with it.

Detection of botulinum neurotoxin serotype A, B, and F proteolytic activity in complex matrices with picomolar to femtomolar sensitivity

Rapid, high-throughput assays that detect and quantify botulinum neurotoxin (BoNT) activity in diverse matrices are required for environmental, clinical, pharmaceutical, and food testing. The current standard, the mouse bioassay, is sensitive but is low in throughput and precision. In this study, we present three biochemical assays for the detection and quantification of BoNT serotype A, B, and F proteolytic activities in complex matrices that offer picomolar to femtomolar sensitivity with small assay volumes and total assay times of less than 24 h. These assays consist of magnetic beads conjugated with BoNT serotype-specific antibodies that are used to purify BoNT from complex matrices before the quantification of bound BoNT proteolytic activity using the previously described BoTest reporter substrates. The matrices tested include human serum, whole milk, carrot juice, and baby food, as well as buffers containing common pharmaceutical excipients. The limits of detection were below 1 pM for BoNT/A and BoNT/F and below 10 pM for BoNT/B in most tested matrices using 200-μl samples and as low as 10 fM for BoNT/A with an increased sample volume. Together, these data describe rapid, robust, and high-throughput assays for BoNT detection that are compatible with a wide range of matrices.

Diplopia as the primary presentation of foodborne botulism

Foodborne botulism is a serious condition caused by Clostridium botulinum neurotoxin. Clinically, botulism presents as bilateral cranial nerve neuropathy and descending paralysis. We report a unique presentation of botulism to remind clinicians of this potentially fatal condition. In this observational case report initial evaluation showed only esodeviation. This progressed to unilateral cranial nerve six (CN VI) paresis along with systemic signs. Clinical diagnosis was made based on in-depth history and concurrent symptoms in three other patients. Foodborne botulism presenting as diplopia and unilateral motility deficits is rare and can represent a diagnostic and therapeutic challenge to the ophthalmologist.

Medical treatment for botulism

BACKGROUND

Botulism is an acute paralytic illness caused by a neurotoxin produced by Clostridium botulinum. Supportive care, including intensive care, is key but the role of other medical treatments is unclear.

OBJECTIVES

To assess the effects of medical treatments on mortality, duration of hospitalization, mechanical ventilation, tube or parenteral feeding and risk of adverse events in botulism.

SEARCH STRATEGY

We searched the Cochrane Neuromuscular Disease Group Specialized Register (10 January 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) (10 January 2010 in The Cochrane Library, Issue 4 2010), MEDLINE (January 1966 to January 2011) and EMBASE (January 1980 to January 2011). We reviewed bibliographies, and contacted authors and experts.

SELECTION CRITERIA

We included randomized and quasi-randomized controlled trials examining the medical treatment of any of the four major types of botulism (infant intestinal botulism, food-borne botulism, wound botulism and adult intestinal toxemia). Medical treatments included equine serum trivalent botulism antitoxin, human-derived botulinum immune globulin, plasma exchange, 3,4-diaminopyridine and guanidine.

DATA COLLECTION AND ANALYSIS

Two authors selected studies, assessed risk of bias and extracted data independently onto data extraction forms.Our primary outcome was in-hospital death from any cause occurring within four weeks. Secondary outcomes were death occurring within 12 weeks, duration of hospitalization, mechanical ventilation, tube or parenteral feeding and risk of adverse events.

MAIN RESULTS

A single randomized controlled trial met the inclusion criteria. This trial evaluated human-derived botulinum immune globulin for the treatment of infant botulism. This study included 59 treatment patients and 63 control patients. There were no deaths in either group making any treatment effect on mortality inestimable. There was a significant benefit in the treatment group on duration of hospitalization (mean difference (MD) 3.10 weeks, 95% confidence interval (CI) 1.68 to 4.52), mechanical ventilation (MD 2.60 weeks, 95% CI 1.14 to 4.06), and tube or parenteral feeding (MD 6.40 weeks, 95% CI 2.80 to 10.00) but not on risk of adverse events or complications (relative risk reduction 0.92, 95% CI 0.72 to 1.18; absolute risk reduction 0.06, 95% CI 0.22 to -0.11).

AUTHORS' CONCLUSIONS

There is good evidence supporting the use of human-derived botulinum immune globulin in infant intestinal botulism. A single randomized controlled trial demonstrated significant decreases in the duration of hospitalization, mechanical ventilation and tube or parenteral feeding among treated patients. Our search did not reveal any evidence examining the use of other medical treatments including serum trivalent botulism antitoxin.

Entzündliche Erkrankungen

Unter einer Meningitis versteht man eine Entzündung von Pia mater und Arachnoidea. Das Erregerspektrum ist weit und reicht von Bakterien, die hämatogen-metastatisch, fortgeleitet oder durch offene Hirnverletzung zur eitrigen Meningitis führen, über Viren zu Pilzen und Parasiten. Insbesondere bei den unbehandelt häufig letal verlaufenden eitrigen Meningitiden ist eine rasche Diagnose mit Erregernachweis notwendig. Unverzüglich ist daraufhin eine spezifische, der regionalen Resistenzentwicklung angepasste Therapie einzuleiten. Die meningeale Affektion im Rahmen einer Listeriose oder Tuberkulose verdient aufgrund des klinischen Bildes, des Verlaufs und der spezifischen Therapie besondere Beachtung. Die fungalen Infektionen werden, da klinisch häufig als Meningoenzephalitis imponierend, in Abschn. 33.3 abgehandelt.

Clostridium botulinum in the post-genomic era

Foodborne botulism is a severe neuroparalytic disease caused by consumption of botulinum neurotoxin formed by strains of proteolytic Clostridium botulinum and non-proteolytic C. botulinum during their growth in food. The botulinum neurotoxin is the most potent substance known, with as little as 30-100 ng potentially fatal, and consumption of just a few milligrams of neurotoxin-containing food is likely to be sufficient to cause illness and potentially death. In order to minimise the foodborne botulism hazard, it is necessary to extend understanding of the biology of these bacteria. This process has been recently advanced by genome sequencing and subsequent analysis. In addition to neurotoxin formation, endospore formation is also critical to the success of proteolytic C. botulinum and non-proteolytic C. botulinum as foodborne pathogens. The endospores are highly resistant, and enable survival of adverse treatments such as heating. To better control the botulinum neurotoxin-forming clostridia, it is important to understand spore resistance mechanisms, and the physiological processes involved in germination and lag phase during recovery from this dormant state.

Clostridial toxins

Clostridia produce the highest number of toxins of any type of bacteria and are involved in severe diseases in humans and other animals. Most of the clostridial toxins are pore-forming toxins responsible for gangrenes and gastrointestinal diseases. Among them, perfringolysin has been extensively studied and it is the paradigm of the cholesterol-dependent cytolysins, whereas Clostridium perfringens epsilon-toxin and Clostridium septicum alpha-toxin, which are related to aerolysin, are the prototypes of clostridial toxins that form small pores. Other toxins active on the cell surface possess an enzymatic activity, such as phospholipase C and collagenase, and are involved in the degradation of specific cell-membrane or extracellular-matrix components. Three groups of clostridial toxins have the ability to enter cells: large clostridial glucosylating toxins, binary toxins and neurotoxins. The binary and large clostridial glucosylating toxins alter the actin cytoskeleton by enzymatically modifying the actin monomers and the regulatory proteins from the Rho family, respectively. Clostridial neurotoxins proteolyse key components of neuroexocytosis. Botulinum neurotoxins inhibit neurotransmission at neuromuscular junctions, whereas tetanus toxin targets the inhibitory interneurons of the CNS. The high potency of clostridial toxins results from their specific targets, which have an essential cellular function, and from the type of modification that they induce. In addition, clostridial toxins are useful pharmacological and biological tools.