Emergence of colistin resistance in multidrug-resistant Klebsiella pneumoniae and Escherichia coli strains isolated from cancer patients

• Published in: Annals of clinical microbiology and antimicrobials Vol. 18; no. 1; p. 40
• Main Authors: Zafer, Mai M, El-Mahallawy, Hadir A, Abdulhak, Asmaa, Amin, Magdy A, Al-Agamy, Mohamed H, Radwan, Hesham H
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 12.12.2019; BioMed Central; BMC
• Subjects: Antibacterial agents; Antibiotics; Bacteria; Bacterial infections; Cancer; Cancer patients; Care and treatment; Colistin; Colistin - pharmacology; Colistin-resistance; Deoxyribonucleic acid; Disease susceptibility; DNA; Drug Resistance, Bacterial - genetics; E coli; Egypt; Emergence; Escherichia coli; Escherichia coli - drug effects; Escherichia coli - genetics; Escherichia coli Proteins - genetics; Genes; Genes, Bacterial; Genetic aspects; Gram-negative bacteria; Health risks; Hospitalization; Humans; Infections; Klebsiella; Klebsiella pneumoniae; Klebsiella pneumoniae - drug effects; Klebsiella pneumoniae - genetics; Lipopolysaccharides; mcr-1; mcr-2; Membrane Proteins - genetics; Meropenem; mgrB; Microbial drug resistance; Microbial Sensitivity Tests; Multidrug resistance; Multidrug resistant organisms; Multilocus Sequence Typing; Mutation; Neoplasms; Pneumonia; Public health; Public health movements; Tigecycline; Egypt; Cairo Egypt; United Kingdom > UK; France; China; Colistin-resistance; Escherichia coli; Egypt; mgrB; Klebsiella pneumoniae; mcr-1; mcr-2
• ISSN: 1476-0711; 1476-0711
• DOI: 10.1186/s12941-019-0339-4

Colistin resistance is mainly driven by alterations in the Gram-negative outer membrane lipopolysaccharides and is caused, in most cases, by mutations in mgrB gene. However, the recent emergence of plasmid-encoded colistin resistance among Enterobacteriaceae strains represents a serious threat to global public health. In this paper we have investigated the rates of colistin resistance and the underlying mechanisms in 450 Klebsiella pneumoniae and Escherichia coli isolates obtained from cancer patients in Egypt. Colistin susceptibility and minimum inhibitory concentrations were determined according to the European Committee on Antimicrobial Susceptibility Testing, by broth microdilution, and by E-test. The mcr-1, mcr-2 and mgrB genes were detected by PCR and then sequenced. Clonal diversity in colistin-resistant K. pneumoniae was evaluated by multilocus sequence typing. Forty (8.8%) colistin-resistant isolates, including 22 K. pneumoniae and 18 E. coli, were isolated over 18 months. Of these, 50% were carbapenem-resistant, out of which nine were bla and seven bla positive. The mechanisms of colistin resistance could be revealed only in three of the 40 resistant strains, being represented by mcr-1 in one bla -positive E. coli strain and in one K. pneumoniae ST11 and by mgrB mutations, detected in one K. pneumoniae isolate. None of the studied isolates harbored mcr-2. Our results demonstrate a high frequency of colistin resistance in enterobacterial strains isolated from cancer patients, but a low prevalence of the most well known resistance mechanisms.