The Growing Threat of Antibiotic Resistance in Children

Abstract

Antimicrobial resistance is a global public health threat and a danger that continues to escalate. These menacing bacteria are having an impact on all populations; however, until recently, the increasing trend in drug-resistant infections in infants and children has gone relatively unrecognized. This article highlights the current clinical and molecular data regarding infection with antibiotic-resistant bacteria in children, with an emphasis on transmissible resistance and spread via horizontal gene transfer.

Keywords: Bacteria; Child; Drug resistance; Epidemiology; Genetic structures; Infection; Public health; β-Lactamases.

Figure 1. Mechanisms of Antibiotic Resistance and Horizontal Gene Transfer

Four main systems of antibiotic resistance are highlighted: Encoding enzymes that modify or degrade antibiotics; Genes that modify the molecular targets for antibiotics; Genes that decrease permeability through cell wall or outer membrane changes; or by alterations which increase active drug efflux. The three main mechanisms of horizontal gene transfer: transduction (via vectors such as bacteriophages), transformation (mainly by homologous recombination), and conjugation; the latter involves transfer of DNA via physical cell to cell contact (mating) and is the most significant contributor to the dissemination of antibiotic resistance. The conjugative plasmid is enlarged to show the complex set of genetic elements important in transmissible resistance.

Figure 2. The Chain of Transmission of Antibiotic Resistance

Antibiotic resistance at the human–animal–environment interface is exceptionally complex. The driver of antibiotic-resistance in bacteria is mainly due to the selective pressure created by the broad use of antibiotics in agriculture, livestock, veterinary and human medical practices. With a continuum of transmission routes and vehicles of resistance, each reservoir of resistance serves a perpetual source for antibiotic-resistant bacteria into the other reservoirs within the chain of transmission.

Figure 3. Controlling the Spread of CRE in Pediatric Healthcare Settings – A Conceptual Algorithm

Size of text in each box represents the relative amount or frequency of the element. Abbreviations: CRE, Carbapenem Resistant Enterobacteriaceae; K. pneumoniae, Klebsiella pneumoniae; AmpC, AmpC Cephalosporinases; ESBL, Extended Spectrum Beta-Lactamases; Porin, Outer Membrane Porin Channel Alteration; SME, Serratia marcescens enzyme; KPC, Klebsiella pneumoniae carbapenemase; MBL, Metallo-Beta-Lactamase; OXA, Oxacillin-hydrolyzing Beta-Lactamase; ALL, All sources; HAIs, Healthcare-Associated Infections; IC, Infection Control; VAC, Ventilator-Associated Complication; Catheter Bundle, aimed at reducing device-related infections.