揭示巴西亚马逊地区囊性纤维化患者肺部感染中铜绿假单胞菌的分子流行病学。

Unveiling the molecular epidemiology of Pseudomonas aeruginosa in lung infections among cystic fibrosis patients in the Brazilian Amazon.

作者信息

Gouveia Maria Isabel Montoril, do Socorro Nascimento Falcão Sarges Edilene, Dos Reis Herald Souza, Sardinha Danielle Melo, Dos Santos Pabllo Antonny Silva, Ribeiro Layana Rufino, Silva Marcos Jessé Abrahão, de Melo Marcos Vinicios Hino, Quaresma Ana Judith Pires Garcia, Brasiliense Danielle Murici, Lima Luana Nepomuceno Godim Costa, Lima Karla Valéria Batista, Rodrigues Yan Corrêa

机构信息

Program in Epidemiology and Health Surveillance (PPGEVS), Evandro Chagas Institute (IEC), Ministry of Health, Ananindeua, PA, 67030-000, Brazil.

Bacteriology and Mycology Section, Evandro Chagas Institute (SEBAC/IEC), Ministry of Health, Ananindeua, PA, 67030-000, Brazil.

出版信息

BMC Microbiol. 2025 Apr 9;25(1):203. doi: 10.1186/s12866-025-03920-w.

DOI:10.1186/s12866-025-03920-w

PMID:40205346

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11984257/

Abstract

BACKGROUND

Pseudomonas aeruginosa is a major pathogen in cystic fibrosis (CF), where chronic and intermittent infections significantly affect patient outcomes. This study aimed to investigate the molecular epidemiology of P. aeruginosa in CF patients from the Brazilian Amazon, focusing on genotypic diversity, resistance profiles, and virulence factors.

METHODS

A cross-sectional study included 72 P. aeruginosa isolates from 44 CF patients treated at a regional reference center between 2018 and 2019. Antimicrobial susceptibility patterns were determined using VITEK-2 system and Kirby-Bauer disk diffusion. Virulotypes were defined by molecular detection of exoS, exoU, exoT, exoY, algU, and algD genes. Genetic diversity was assessed using multilocus sequence typing (MLST). Demographic data, clinical severity, and spirometry results were also collected.

RESULTS

Among the patients, 54.55% experienced intermittent infections, while 45.45% had chronic infections. Chronic infections were associated with older age, lower FEV1, and reduced Shwachman-Kulczycki scores. Multidrug resistance was observed in 15.3% of isolates, particularly against ciprofloxacin and piperacillin/tazobactam. The exoU gene was present in 55.56% of isolates, an uncommon finding in CF populations. High genetic diversity was evident, with 37 sequence types (STs), including 14 novel STs. High-risk clones (HRCs) constituted 25% of isolates, with ST274 being the most prevalent (12.5%). Longitudinal analysis revealed transient colonization in intermittent infections, while chronic infections were dominated by stable clones.

CONCLUSION

This study highlights the molecular and clinical dynamics of P. aeruginosa in CF patients from the Brazilian Amazon. Chronic infections were linked to severe lung impairment , while intermittent infections were dominated by HRCs. These findings underscore the need for robust genotypic surveillance to mitigate the burden of P. aeruginosa in CF populations.

摘要

背景

铜绿假单胞菌是囊性纤维化（CF）中的主要病原体，其慢性和间歇性感染会显著影响患者的预后。本研究旨在调查巴西亚马逊地区CF患者中铜绿假单胞菌的分子流行病学，重点关注基因型多样性、耐药谱和毒力因子。

方法

一项横断面研究纳入了2018年至2019年间在一个地区参考中心接受治疗的44例CF患者的72株铜绿假单胞菌分离株。使用VITEK-2系统和 Kirby-Bauer纸片扩散法确定抗菌药物敏感性模式。通过对外毒素S（exoS）、外毒素U（exoU）、外毒素T（exoT）、外毒素Y（exoY）、algU和algD基因的分子检测来定义毒力型。使用多位点序列分型（MLST）评估遗传多样性。还收集了人口统计学数据、临床严重程度和肺功能检查结果。

结果

在患者中，54.55%经历了间歇性感染，而45.45%患有慢性感染。慢性感染与年龄较大、第一秒用力呼气容积（FEV1）较低以及施瓦赫曼-库尔奇茨基评分降低有关。15.3%的分离株观察到多重耐药，特别是对环丙沙星和哌拉西林/他唑巴坦。55.56%的分离株中存在exoU基因，这在CF人群中并不常见。遗传多样性很高，有37种序列类型（STs），包括14种新的STs。高风险克隆（HRCs）占分离株的25%，其中ST274最为常见（12.5%）。纵向分析显示间歇性感染中存在短暂定植，而慢性感染则以稳定克隆为主。