The world of the gut microbiota in healthy or sick people is still a very vast field of study today. The fundamental objective of research on the human microbiota is to determine its structure, the dynamics of the relationships between the bacteria that compose it, the substances produced and consumed, the interaction between it and the host and the differences in healthy and sick people. Particular attention has recently been paid to infections with carbapenem-resistant Klebsiella pneumoniae (hence Multi Drug Resistant, MDR) following endoscopic retrograde cholangiopancreatography (ERCP). In our polyclinic, the risk of an epidemic of K. pneumoniae MDR in 2012-2013 was suspected, with a succession of possible sporadic cases. In our laboratory an epidemiological study was carried out on 25 strains of Klebsiella pneumoniae, the result of which highlighted the epidemiological transition between two patients. Starting from the evidence of the risk of KPC outbreak following ERCP and on the basis of the knowledge acquired on the intestinal microbiota, we decided to study the resident or bile-colonizing microbiota using "cultuomics" techniques, nowadays more and more supportive to the analyzes metagenomics. The study was performed on 77 bile samples taken intra-operative from patients admitted to the General Surgery Department of the Campus Bio-Medico Polyclinic in Rome, between January 2014 and January 2016. 61 samples were positive for plate culture. Of the 168 isolates identified, 87 were Gram positive, 67 Gram negative and 14 yeast fungi. 50 isolates showed particular resistance to antibiotics (including 6 KPC). The analysis of the dendograms of the protein spectra obtained by MALDI-TOF MS highlights the precision of the instrument which perfectly divides the isolates into different clusters according to the species and antibiotic resistance.
Il mondo del microbiota intestinale in persone sane o malate è ancora oggi un campo di studio molto vasto. L'obiettivo fondamentale della ricerca sul microbiota umano è quello di determinarne la struttura, la dinamica dei rapporti tra i batteri che lo compongono, le sostanze prodotte e consumate, l'interazione tra esso e l'ospite e le differenze nelle persone sane e malate. Particolare attenzione è stata recentemente prestata alle infezioni da Klebsiella pneumoniae resistente ai carbapenemi (quindi Multi Drug Resistant, MDR) susseguenti a colangiopancreatografia retrograda endoscopica (CPRE). Nel nostro policlinico si è sospettato il rischio di un'epidemia di K. pneumoniae MDR nel 2012-2013, con il susseguirsi di possibili casi sporadici. Nel nostro laboratorio è stato effettuato uno studio epidemiologico su 25 ceppi di Klebsiella pneumoniae, il cui risultato ha evidenziato il passaggio epidemiologico tra due pazienti. Partendo dall'evidenza del rischio di outbreak di KPC in seguito a CPRE e sulla base delle nozioni acquisite sul microbiota intestinale, abbiamo deciso di voler studiare il microbiota residente o colonizzante la bile utilizzando le tecniche "cultuomics", oggigiorno sempre più di supporto alle analisi metagenomiche. Lo studio è stato eseguito su 77 campioni di bile prelevata in sede intra-operatoria da pazienti ricoverati presso il reparto di Chirurgia generale del Policlinico Campus Bio-Medico di Roma, tra gennaio 2014 e gennaio 2016. 61 campioni sono risultati positivi alla coltura in piastra. Su 168 isolati identificati, 87 erano Gram positivi, 67 Gram negativi e 14 funghi lievitiformi. 50 isolati hanno mostrato particolari resistenze agli antibiotici (tra questi 6 KPC). L'analisi dei dendogrammi degli spettri proteici ottenuti tramite MALDI-TOF MS mette in evidenza la precisione dello strumento che divide perfettamente gli isolati in clusters differenti a seconda della specie e delle resistenze antibiotiche.
Il microbiota residente e colonizzante della bile / Genoveffa Francesca Sapia , 2016 Mar 11. 28. ciclo
Il microbiota residente e colonizzante della bile
2016-03-11
Abstract
The world of the gut microbiota in healthy or sick people is still a very vast field of study today. The fundamental objective of research on the human microbiota is to determine its structure, the dynamics of the relationships between the bacteria that compose it, the substances produced and consumed, the interaction between it and the host and the differences in healthy and sick people. Particular attention has recently been paid to infections with carbapenem-resistant Klebsiella pneumoniae (hence Multi Drug Resistant, MDR) following endoscopic retrograde cholangiopancreatography (ERCP). In our polyclinic, the risk of an epidemic of K. pneumoniae MDR in 2012-2013 was suspected, with a succession of possible sporadic cases. In our laboratory an epidemiological study was carried out on 25 strains of Klebsiella pneumoniae, the result of which highlighted the epidemiological transition between two patients. Starting from the evidence of the risk of KPC outbreak following ERCP and on the basis of the knowledge acquired on the intestinal microbiota, we decided to study the resident or bile-colonizing microbiota using "cultuomics" techniques, nowadays more and more supportive to the analyzes metagenomics. The study was performed on 77 bile samples taken intra-operative from patients admitted to the General Surgery Department of the Campus Bio-Medico Polyclinic in Rome, between January 2014 and January 2016. 61 samples were positive for plate culture. Of the 168 isolates identified, 87 were Gram positive, 67 Gram negative and 14 yeast fungi. 50 isolates showed particular resistance to antibiotics (including 6 KPC). The analysis of the dendograms of the protein spectra obtained by MALDI-TOF MS highlights the precision of the instrument which perfectly divides the isolates into different clusters according to the species and antibiotic resistance.File | Dimensione | Formato | |
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