A high number of multidrug-resistant and predominant genetically related cluster of Shigella flexneri strains isolated over 34 years in Brazil

Abstract

Shigella flexneri has been a major public health problem in developing countries. This work analyzed the frequency of 16 virulence genes, the genotypic diversity, and the antimicrobial resistance profiles of 130 S. flexneri strains isolated in Brazil. The ipaH gene was found in all the 130 strains. The frequencies of the other genes were variable ial (88.5%), sigA (82.3%), iuc (74.6%), virA (73%), pic (72.3%), virF (57.7%), sat (48.5%), ipaBCD (37%), sen (36%), set1A (35.4%), sepA (30%), set1B (30%), virB (14%), icsA (10%), and ipgD (5.4%). A total of 57 (43.8%) strains were multidrug-resistant. ERIC-PCR grouped 96 of the strains into a single cluster with ≥ 70.4% of similarity, 75 of these strains presented a similarity ≥ 80.9%. PFGE grouped 120 of the strains into a single cluster with 57.4% of similarity and 82 of these strains presented a similarity ≥ 70.6%. In conclusion, the high frequency of some virulence genes reinforces the pathogenic potential of the strains studied. The high rates of MDR strains are alarming once it may lead to failure when antimicrobial treatment is necessary. Genotype techniques reveled a major cluster with high genetic similarity including S. flexneri strains from the different Brazilian states and distinct years of isolation, showing that they probably emerged from a common ancestor.

Prevalence of Multidrug-Resistant and Extended-Spectrum Beta-Lactamase-Producing Shigella Species in Asia: A Systematic Review and Meta-Analysis

“…Resistance to third-generation cephalosporins has also been linked to the production of ESBLs, conferring resistance to β-lactamases [ 90 ]. Our pooled estimate of MDR Shigella in Asia was 68.7% (95% CI: 59.9–77.5) ( Figure 5 )—substantially higher than that in a report from Brazil (43.8%) [ 91 ], but much lower than reports from Egypt (88.0%) [ 92 ] and Ethiopia (83.2%) [ 82 ]. The highest prevalence of MDR Shigella spp.…”

Análise do potencial patogênico, diversidade genotípica e perfil de resistência de linhagens de Shigella flexneri isoladas por 34 anos em diferentes Estados do Brasil

“…No Brasil existem relativamente poucos estudos que investigaram a resistência de linhagens de S. flexneri a diferentes classes de antimicrobianos, porém estes demonstraram a presença de resistência a vários antimicrobianos utilizados rotineiramente na clínica (SIDRIM et al, 1998;MESQUITA et al, 2009;BASTOS et al, 2010;BASTOS & LOUREIRO 2011;GONZALES et al, 2020). Todos esses estudos publicados no Brasil evidenciaram a acentuada resistência de S. flexneri a diversos antimicrobianos e a necessidade de um monitoramento contínuo dos padrões de resistência de Shigella spp.…”

“…No Brasil, os poucos estudos que caracterizam molecularmente linhagens de Shigella spp. por ERIC-PCR demonstraram que esta metodologia é robusta e eficiente (PENATTI et al, 2007;SERIBELLI et al, 2016;GONZALES et al, 2020).…”

“…A análise do padrão de bandas das diferentes linhagens é realizada por softwares especializados que comparam as linhagens estabelecendo a similaridade genômica entre elas (SINGH et al, 2006). Assim, o PFGE é uma das técnicas de tipagem molecular que possui um grande poder discriminatório e vem sendo aplicada com sucesso na tipagem de uma quantidade numerosa de espécies bacterianas, isoladas no Brasil e em outros locais do mundo (TENOVER et al, 1997;RIBOT et al, 2001;DENIS et al, 2008;GOERING, 2010;O'LEARY et al, 2011;ABLEY et al, 2012;WIECZOREK et al, 2013;GONZALES et al, 2020).…”

“…No Brasil, há relativamente poucos trabalhos publicados que tiparam linhagens de Shigella spp. por PFGE (ANGELINI et al, 2009, LIMA et al, 1997SERIBELLI et al, 2016;GONZALES et al, 2020). Em todos os estudos a metodologia discriminou adequadamente as linhagens analisadas.…”