Intestinal decolonization of Enterobacteriaceae producing extended-spectrum β-lactamases (ESBL): a retrospective observational study in patients at risk for infection and a brief review of the literature.
BACKGROUND
Multidrug-resistant Escherichia coli and other enteric bacteria producing extended-spectrum β-lactamases (ESBL) have emerged as an important cause of invasive infection. Targeting the primary (intestinal) niche by decolonization may be a valuable approach to decrease the risk of relapsing infections and to reduce transmission of ESBL-producing enteric pathogens.


METHODS
In a retrospective observational study we evaluated the efficacy of intestinal decolonization treatment using orally administered colistin or other non-absorbable agents given for 2 to 4 weeks in adult patients with previous relapsing infection and persistent intestinal colonization with ESBL-positive Enterobacteriaceae (ESBL-E). Eradication success was defined as negative rectal swab or stool culture at the end of treatment and at follow up-2 weeks after treatment discontinuation.


RESULTS
First-line decolonization treatment led to eradication of ESBL-E in 19/45 patients (42%, 7/18 low-dose [4 × 1 million units] colistin, 3/12 high-dose [4 × 2 million units] colistin, 9/15 rifaximin [2 × 400 mg]), and secondary/salvage treatment was successful in 8/13 patients (62 %, 20 treatment episodes). Late follow-up showed that 7/13 patients (54%) with successful initial or salvage decolonization became recolonized within 3 months after post-treatment assessment while all eight of the patients failing initial or salvage decolonization treatment with late follow-up remained colonized. A narrative review of the literature confirms the limited efficacy of non-absorbable antibiotics including conventional selective digestive tract decolonization (SDD)-like combination regimens for eradicating multidrug-resistant enteric bacteria from the intestinal tract.


CONCLUSIONS
At present, there is no clear evidence of a significant decolonization efficacy using single-drug treatment with oral non-absorbable antibiotics. More effective regimens are needed and a better definition of at risk patients is required for planning meaningful randomized controlled studies in this field.
Division of Infectious Diseases, Department of Medicine, Albert-Ludwigs-University Hospital & Medical Center, Hugstetter Straße 55, D-79106, Freiburg, Germany. siegbert.rieg@uniklinik-freiburg.de.
Siegbert
S
Rieg
Division of Infectious Diseases, Department of Medicine, Albert-Ludwigs-University Hospital & Medical Center, Hugstetter Straße 55, D-79106, Freiburg, Germany. marc.kuepper@uniklinik-freiburg.de.
M Fabian
MF
Küpper
Division of Infectious Diseases, Department of Medicine, Albert-Ludwigs-University Hospital & Medical Center, Hugstetter Straße 55, D-79106, Freiburg, Germany. katja.dewith@uniklinikum-dresden.de.|Center for Chronic Immunodeficiency, Albert-Ludwigs-University Hospital & Medical Center, Freiburg, Germany. katja.dewith@uniklinikum-dresden.de.|Present address: Clinical Infectious Diseases and Antibiotic Stewardship Unit, Carl Carus University Hospital, Dresden, Germany. katja.dewith@uniklinikum-dresden.de.
Katja
K
de With
Department of Microbiology, Albert-Ludwigs-University Hospital & Medical Center, Freiburg, Germany. annerose.serr@uniklinik-freiburg.de.
Annerose
A
Serr
Division of Infectious Diseases, Department of Medicine, Albert-Ludwigs-University Hospital & Medical Center, Hugstetter Straße 55, D-79106, Freiburg, Germany. juergen.bohnert@med.uni-jena.de.|Present address: Institute of Medical Microbiology, University Hospital, Jena, Germany. juergen.bohnert@med.uni-jena.de.
Jürgen A
JA
Bohnert
Division of Infectious Diseases, Department of Medicine, Albert-Ludwigs-University Hospital & Medical Center, Hugstetter Straße 55, D-79106, Freiburg, Germany. kern@if-freiburg.de.
Winfried V
WV
Kern
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D003091:Colistin / Q000008:administration & dosage / Q000627:therapeutic use*; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000378:metabolism / Q000472:pathogenicity; D004756:Enterobacteriaceae Infections / Q000382:microbiology / Q000517:prevention & control*; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism / Q000472:pathogenicity; D005260:Female; D000069196:Gastrointestinal Microbiome / Q000187:drug effects; D006801:Humans; D007422:Intestines / Q000187:drug effects / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012294:Rifamycins / Q000627:therapeutic use; D000078262:Rifaximin; D016896:Treatment Outcome; D055815:Young Adult; D001618:beta-Lactamases / Q000378:metabolism*
D000900:Anti-Bacterial Agents; D012294:Rifamycins; D001618:beta-Lactamases; D000078262:Rifaximin; D003091:Colistin