An adult case with shigellosis-associated encephalopathy

The genomic epidemiology of shigellosis in South Africa

Shigellosis, a leading cause of diarrhoeal mortality and morbidity globally, predominantly affects children under five years of age living in low- and middle-income countries. While whole genome sequence analysis (WGSA) has been effectively used to further our understanding of shigellosis epidemiology, antimicrobial resistance, and transmission, it has been under-utilised in sub-Saharan Africa. In this study, we applied WGSA to large sub-sample of surveillance isolates from South Africa, collected from 2011 to 2015, focussing on Shigella flexneri 2a and Shigella sonnei. We find each serotype is epidemiologically distinct. The four identified S. flexneri 2a clusters having distinct geographical distributions, and antimicrobial resistance (AMR) and virulence profiles, while the four sub-Clades of S. sonnei varied in virulence plasmid retention. Our results support serotype specific lifestyles as a driver for epidemiological differences, show AMR is not required for epidemiological success in S. flexneri, and that the HIV epidemic may have promoted Shigella population expansion.

British Association of Sexual Health and HIV (BASHH) United Kingdom national guideline for the management of sexually transmitted enteric infections 2023

This is the first British Association of Sexual Health and HIV (BASHH) national guideline for the management of sexually transmitted enteric infections (STEI). This guideline is primarily aimed for level 3 sexual health clinics; however, it may also be applicable to other settings such as primary care or other hospital departments where individuals with STEI may present. This guideline makes recommendations on testing, management, partner notification and public health control of STEI.

Antimicrobial resistance in sexually transmitted Shigella in men who have sex with men: A systematic review

BACKGROUND

Outbreaks of sexually transmitted Shigella flexneri and Shigella sonnei in men who have sex with men (MSM) are a major public health issue. While most cases can be managed conservatively, a minority require antimicrobial treatment. Recent reports have highlighted increasing antimicrobial resistant (AMR) strains of Shigella spp. in men who have sex with men. We aimed to systematically review antimicrobial resistance (and decreased antimicrobial sensitivity) in sexually transmitted shigella in men who have sex with men, focussing on macrolides, quinolones, and third generation cephalosporins.

METHODS

We systematically searched 4 bibliographical databases (EMBASE, medline, EMCARE and CINAHL) from January 2011 to November 2021. We used a 2-stage process to assess eligibility: the primary author conducted an initial screen and then 3 authors conducted independent full-text reviews to determine the final eligible manuscripts. We only included manuscripts in English which included men who have sex with men with sexually transmitted shigella where data on antimicrobial resistance was available.

RESULTS

Thirty-nine manuscripts met the inclusion criteria. A majority of the manuscripts (N = 34) described reduced susceptibility or antimicrobial resistant to macrolides, quinolones and third generation cephalosporins in circulating strains of shigella within sexual networks of men who have sex with men. Extensively drug resistant outbreaks of shigella in men who have sex with men have been reported containing genetic markers of ceftriaxone resistance (e.g. BlaCTX-M27) where isolates also contained markers of reduced susceptibility, and antimicrobial resistant to macrolides and quinolones.

CONCLUSION

There is little role for macrolides, quinolones or third generation cephalosporins in the management of sexually transmitted shigella in men who have sex with men. More research is needed to develop novel strategies for shigella control in men who have sex with men, as antimicrobial options are diminishing.

Au Nanoclusters Ameliorate Shigella Infectious Colitis by Inducing Oxidative Stress

Background

Shigella infection has always been a global burden, and it particularly threatens children between the ages of 1 and 5 years. Economically underdeveloped countries are dominated by Shigella flexneri infection. The most effective method to treat Shigella is antibiotics, but with the abuse of antibiotics and the prevalence of multidrug resistance, we urgently need a relatively safe non-antibiotic treatment to replace it. Ultrasmall Au nanoclusters (NCs) have special physical and chemical properties and can better interact with and be internalized by bacteria to disrupt the metabolic balance. The purpose of this study was to explore whether Au NCs may be a substitute for antibiotics to treat Shigella infections.

Methods

Au NCs and Shigella Sf301, R2448, and RII-1 were cocultured in vitro to evaluate the bactericidal ability of Au NCs. The degree of damage and mode of action of Au NCs in Shigella were clearly observed in images of scanning electron microscopy (SEM). In vivo experiments were conducted to observe the changes in body weight, clinical disease activity index (DAI) and colon (including length and histopathological sections) of mice treated with Au NCs. The effect of Au NCs was analysed by measuring the content of lipocalin-2 (LCN2) and Shigella in faeces. Next, the changes in Shigella biofilm activity, the release of reactive oxygen species (ROS), the changes in metabolism-related and membrane-related genes, and the effect of Au NCs on the body weight of mice were determined to further analyse the mechanism of action and effect.

Results

Au NCs (100 μM) interfered with oxidative metabolism genes, induced a substantial increase in ROS levels, interacted with the cell membrane to destroy it, significantly killed Shigella, and effectively alleviated the intestinal damage caused by Shigella in mice. The activity of the biofilm formed by Shigella was reduced.

Conclusion

The effective antibacterial effect and good safety suggest that Au NCs represent a good potential alternative to antibiotics to treat Shigella infections.

Shigellosis Presenting as Meningism

Shigella is a common cause of gastroenteritis and can also lead to serious complications such as dehydration, seizures, hemolytic uremic syndrome, and neurological complications. In this paper, we describe a case of a 39-year-old man who was admitted septic, with altered mental status and gastrointestinal symptoms. During the evaluation, he was found to have positive meningeal signs, non-anion gap metabolic acidosis, enteric panel positive for Shigella flexneri, positive IgG for Strongyloides, and pancolitis on computed tomography (CT) of the abdomen and pelvis. He was treated for infectious colitis and initially treated empirically for meningitis, but antibiotics were later discontinued due to rapid improvement of meningeal signs. To reduce the risk of disseminated infection, the patient was also treated for Strongyloides.

A propósito de complicaciones infrecuentes de enfermedades comunes. Síndrome de Ekiri

La infección por enterobacterias desencadena usualmente síntomas gastrointestinales caracterizados por vómito, diarrea y dolor abdominal, de severidad y curso variable. El compromiso extraintestinal esta descrito, inclusive sin las manifestaciones gastrointestinales clásicas lo que favorece diagnósticos y tratamientos tardíos pudiendo llegar a ser incapacitantes y letales. El síndrome de Ekiri, también denominado síndrome de encefalopatía letal tóxico, se caracteriza por una disfunción aguda del sistema nervioso central secundaria a infección por enterobacterias las cuales favorecen el desarrollo de microtrombos a nivel cerebral con inflamación mediada por el factor de necrosis tumoral α e IL- 1β y disfunción de la barrera hematoencefálica con una alta tasa de mortalidad. Dentro de nuestro conocimiento, presentamos el primer caso reportado en Colombia sobre el síndrome de Ekiri.

Early postoperative seizures after vocal fold surgery attributed to shigellosis

A 44-year-old previously healthy woman underwent surgery of the vocal folds and developed early postoperative seizures caused by an unusual aetiology. Clinical assessment and laboratory results revealed that the patient suffered from an acute-onset shigellosis infection which was thought to be the cause of her early postoperative seizures. The shigellosis infection was treated with azithromycin which resulted in rapid clinical improvement, and the seizures were successfully managed with benzodiazepines, sodium valproate and levetiracetam. To our knowledge, this is the first reported case of shigellosis-induced seizures in an adult in the peri-operative period. Early detection of the aetiology of seizures is crucial to ensure appropriate management and a safe patient outcome.