title: Long-term carriage of Klebsiella pneumoniae carbapenemase-2-producing K pneumoniae after a large single-center outbreak in Germany.
abstract: BACKGROUND
  The natural progress of intestinal colonization with Klebsiella pneumoniae carbapenemase-2-producing K pneumoniae (KPC-2-KP) is almost unknown.
  
  
  METHODS
  After a large, single-center outbreak of KPC-2-KP, we analyzed carrier prevalence through retrospective and prospective investigation of intestinal KPC-2-KP carriage 1 month, 3 months, 6 months, 1 year, and 2 years after acquisition, defined as the earliest date of KPC-2-KP detection. Rectal swabs or stool samples were collected at baseline and at each visit and submitted for both culture and KPC-specific polymerase chain reaction. Resolution of intestinal KPC-2-KP carriage was defined as a minimum of 3 consecutive negative polymerase chain reaction test results separated by at least 48 hours.
  
  
  RESULTS
  In patients available for long-term evaluation 26 out of 84 patients (31%) tested negative for KPC-2-KP after 1 month, 14 out of 34 (41%) after 3 months, 17 out of 26 (65%) after 6 months, 14 out of 19 (74%) after 1 year, and 5 out of 6 (83%) after 2 years. Decolonization of KPC-2-KP was hampered in patients with prolonged or repeated hospitalization (P = .044-.140, depending on the time interval). Two patients retested positive for KPC-2-KP after they had previously shown 3 consecutive negative tests. The longest positive KPC-2-KP carrier status so far was observed after nearly 40 months (1,191 days).
  
  
  CONCLUSIONS
  The majority of patients experienced spontaneous decolonization within 6 months after acquisition, mainly after discharge from the hospital. However, long-term carriage of >3 years is possible. Appropriate infection control measures must be taken when these patients are readmitted to health care facilities. A series of at least 4 consecutive negative rectal swabs or stool samples separated by sufficient time intervals appears necessary before the declaration of successful KPC-2-KP decolonization is made.
authors.affiliation: Division of Infectious Diseases and Tropical Medicine, Department of Gastroenterology and Rheumatology, Leipzig University Hospital, Leipzig, Germany. Electronic address: christoph.luebbert@medizin.uni-leipzig.de.
authors.forename: Christoph
authors.initials: C
authors.lastname: Lübbert
authors.affiliation: Institute for Medical Microbiology and Epidemiology of Infectious Diseases, Leipzig University Hospital, Leipzig, Germany; Hospital Hygiene Staff Unit, Leipzig University Hospital, Leipzig, Germany.
authors.forename: Norman
authors.initials: N
authors.lastname: Lippmann
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, Leipzig University Hospital, Leipzig, Germany.
authors.forename: Thilo
authors.initials: T
authors.lastname: Busch
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, Leipzig University Hospital, Leipzig, Germany.
authors.forename: Udo X
authors.initials: UX
authors.lastname: Kaisers
authors.affiliation: Department for Infectious Disease Epidemiology, Robert Koch Institute, Berlin, Germany.
authors.forename: Tanja
authors.initials: T
authors.lastname: Ducomble
authors.affiliation: Department for Infectious Disease Epidemiology, Robert Koch Institute, Berlin, Germany.
authors.forename: Tim
authors.initials: T
authors.lastname: Eckmanns
authors.affiliation: Institute for Medical Microbiology and Epidemiology of Infectious Diseases, Leipzig University Hospital, Leipzig, Germany; Hospital Hygiene Staff Unit, Leipzig University Hospital, Leipzig, Germany.
authors.forename: Arne C
authors.initials: AC
authors.lastname: Rodloff
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001426:Bacterial Proteins / Q000235:genetics*; D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D003430:Cross-Sectional Studies; D004196:Disease Outbreaks; D005243:Feces / Q000382:microbiology; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D007710:Klebsiella Infections / Q000453:epidemiology* / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000201:enzymology* / Q000302:isolation & purification; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011446:Prospective Studies; D012007:Rectum / Q000382:microbiology; D012189:Retrospective Studies; D055815:Young Adult; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D001618:beta-Lactamases; C531581:carbapenemase-2, Klebsiella pneumoniae
keywords: Immunosuppression; Intestinal colonization; KPC; Long-term carriage; Selection pressure