Alcedo Katherine, Ruiz Joaquim, Ochoa Theresa J, Riveros Maribel
Laboratorio de Infectología Pediátrica, Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru.
Laboratorio de Microbiología Molecular y Genómica Bacteriana, Universidad Científica del Sur, Lima, Peru.
Infect Chemother. 2022 Mar;54(1):59-69. doi: 10.3947/ic.2021.0102. Epub 2021 Dec 27.
Antibiotic-resistant can colonize the intestinal tract of healthy children, causing concern when antibiotic resistance is related to the presence of transferable mechanisms, such as extended-spectrum β-lactamases (ESBLs).
Fecal samples from 41 healthy children from two villages of rural Peru were cultured on ceftriaxone-disks. ESBL production was confirmed with double disk synergy. In all ESBL-produced isolates, antibiotic susceptibility to 12 antibacterial agents was established by disk diffusion, while clonal relationships were determined by repetitive extragenic palindromic-polymerase chain reaction (REP-PCR). Presence of ST131 was determined using PCR.
Ceftriaxone-resistant microorganisms were recovered from 39 samples belonging to 22 out of 41 children (53.7%). Of these, 80 ceftriaxone-resistant and two ceftriaxone-intermediate from inside ceftriaxone-halos were confirmed as ESBL-producers. All isolates were multidrug-resistant. In 79/80 (98.8%) ceftriaxone-resistant isolates, the presence of was detected alone (58 isolates, or together with other β-lactamase (, 17 isolates; , 3 isolates; + , 1 isolate), while in one isolate no such ESBL was identified. The two ceftriaxone-intermediate isolates recovered from the same sample, carried a and respectively. Thirty-four different clones were identified, with 4 clones being recovered from different samples from the same child. Twelve clones were disseminated among different children, including 5 clones disseminated between both villages. Two clones, accounting for 3 isolates and both recovered from the same children, belonged to ST131.
This study demonstrates high prevalence of ESBL-carriers among healthy children living in a rural area of Peru, stressing the need for continuous surveillance and search for public health control measures.
抗生素耐药菌可定植于健康儿童的肠道,当抗生素耐药性与可转移机制(如超广谱β-内酰胺酶(ESBLs))的存在相关时,便会引发关注。
从秘鲁农村两个村庄的41名健康儿童采集粪便样本,接种于头孢曲松纸片上进行培养。通过双纸片协同试验确认ESBL的产生。对于所有产ESBL的分离株,采用纸片扩散法测定其对12种抗菌药物的敏感性,同时通过重复外源性回文序列-聚合酶链反应(REP-PCR)确定克隆关系。使用PCR检测ST131的存在情况。
从41名儿童中的22名(53.7%)的39份样本中分离出对头孢曲松耐药的微生物。其中,从头孢曲松抑菌圈内分离出80株对头孢曲松耐药和2株对头孢曲松中介的菌株,确认为产ESBL菌株。所有分离株均为多重耐药。在79/80(98.8%)对头孢曲松耐药的分离株中,单独检测到(58株),或与其他β-内酰胺酶一起检测到(,17株;,3株;+,1株),而在1株分离株中未鉴定出此类ESBL。从同一样本中分离出的2株对头孢曲松中介的菌株,分别携带和。鉴定出34个不同的克隆,其中4个克隆来自同一儿童的不同样本。12个克隆在不同儿童中传播,包括5个克隆在两个村庄之间传播。两个克隆,共3株,均从同一儿童中分离出,属于ST131。
本研究表明,秘鲁农村地区健康儿童中产ESBL携带者的比例很高,强调需要持续监测并寻求公共卫生控制措施。