title: Surgical Site Infections After Liver Transplantation: Emergence of Multidrug-Resistant Bacteria and Implications for Prophylaxis and Treatment Strategies.
abstract: Perioperative antimicrobial prophylaxis is administered to liver transplant (LTx) recipients to prevent surgical site infections (SSIs), but regimens are not standardized, and there are limited effectiveness data. Prevention and treatment of SSIs have been complicated by the emergence of multidrug-resistant (MDR) pathogens.
  
  
  
  We retrospectively reviewed SSIs among 331 LTx recipients at our center in 2010 to 2014.
  
  
  
  Culture-proven superficial and deep SSIs occurred in 3% and 15% of patients, respectively, at median 12.5 and 13.5 days post-LTx. Recipients with superficial SSIs and those without SSIs were similar in demographics, clinical characteristics, length of hospital stay, and mortality. Deep SSIs included abscesses (58%), peritonitis (28%), deep incisional infections (8%), and cholangitis (6%). Rates of deep SSIs were comparable among patients receiving prophylaxis with ampicillin-sulbactam, aztreonam and vancomycin, or tigecycline (P = 0.61). Independent risk factors for deep SSIs were bile leak (P < 0.001) and operative time (P < 0.001). Enterobacteriaceae (42%), Enterococcus spp. (24%), and Candida spp. (15%) were predominant pathogens. Fifty-three percent of bacteria were MDR, including 95% of Enterococcus faecium and 55% of Enterobacteriaceae; 82% of deep SSIs were caused by bacteria resistant to antimicrobials used for prophylaxis, and 58% of patients were treated with an inactive empiric regimen. Deep SSIs were associated with longer lengths of stay (P < 0.001), and higher 90-day and long-term mortality rates (P < 0.001).
  
  
  
  Deep SSIs, including those caused by MDR bacteria, were common after LTx despite prophylaxis with broad-spectrum antimicrobials. Rather than altering prophylaxis regimens, programs should devise empiric treatment regimens that are directed against the most common local pathogens.
authors.affiliation: 1 Division of Infectious Diseases, University of Pittsburgh Medical Center, Pittsburgh, PA. 2 Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA. 3 Infectious Diseases Section, VA Pittsburgh Healthcare System, Pittsburgh, PA. 4 Antibiotic Management Program, University of Pittsburgh Medical Center, Pittsburgh, PA. 5 Department of Pharmacy, University of Pittsburgh Medical Center, Pittsburgh, PA. 6 Thomas E Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA. 7 Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: J Alexander
authors.initials: JA
authors.lastname: Viehman
authors.forename: Cornelius J
authors.initials: CJ
authors.lastname: Clancy
authors.forename: Lloyd
authors.initials: L
authors.lastname: Clarke
authors.forename: Ryan K
authors.initials: RK
authors.lastname: Shields
authors.forename: Fernanda P
authors.initials: FP
authors.lastname: Silveira
authors.forename: Eun J
authors.initials: EJ
authors.lastname: Kwak
authors.forename: Pascalis
authors.initials: P
authors.lastname: Vergidis
authors.forename: Christopher
authors.initials: C
authors.lastname: Hughes
authors.forename: Abhinav
authors.initials: A
authors.lastname: Humar
authors.forename: M Hong
authors.initials: MH
authors.lastname: Nguyen
mesh_terms: D019072:Antibiotic Prophylaxis; D001419:Bacteria / Q000302:isolation & purification*; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D006801:Humans; D016031:Liver Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D013530:Surgical Wound Infection / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology* / Q000517:prevention & control