1 Emergence of Carbapenem-Resistant Klebsiella pneumoniae in an Acute Care Facility and the Potential Risk of Inter- Healthcare Facility Transmission Dawn Terashita MD, MPH Acute Communicable Disease Control Los Angeles County Department of Public Health

Background Carbapenems treat severe infections of ESBL gram-negative pathogens Resistance to carbapenems evolved in Enterobacteriaceae CRKP has become the most common species of carbapenem-resistant Enterobacteriaceae CRKP has rapidly emerged as a new threat in public health 2 Kochar Infect Control Hosp Epidemiol 2009 Jacoby N Engl J Med 2005 Falagas J Antimicrob Chemother 2007

Background CRKP 1 st identified in NC hospital (1999) Infrequently isolated until 2001 –Several extended outbreaks in NY, NJ In 2007, 8% of all Klebsiella isolates were CRKP, compared with fewer than 1% in 2000 Reported in many states and countries 3

Background In October 2007, LAC began receiving occasional CRKP reports from hospitals Sporadic reports continued, mainly to facilitate confirmatory testing for carbapenem resistance In October 2009, LAC was notified of a cluster of cases by facility A 4

Objectives To describe the acute emergence of CRKP in an acute care facility To illustrate the potential risks of inter- healthcare facility transmission 5

Setting Non-profit, acute care healthcare institution providing a full range of medical services with approximately 400 licensed beds Mean daily census is approximately 300 patients (78% occupancy) Average of length of hospital stay is 8 days 6

7 Methods Clinical and Laboratory Standards Institute (CLSI) interpretive criteria for carbapenem resistance in Klebsiella isolates CDC National Healthcare Safety Network (NHSN) MDRO LabID module definitions used to identify new/recurrent cases Case definition: patient in Facility A with CRKP positive culture that meets above criteria

Methods New case: CRKP culture with no prior positive in previous 28 days Recurrent case: subsequent CRKP culture occurring 14–28 days after initial positive Duplicate cases: subsequent CRKP culture occurring 0–14 days after initial positive (excluded from study) 8

Methods Healthcare onset (HO): specimen collected ≥ 4 days after admission Community onset (CO): specimen collected ≤ 3 days after admission 9

Methods Conducted retrospective case finding by reviewing laboratory records from facility A Reviewed medical records for all cases identified for data including: –Demographics –Lab reports (including susceptibilities) –Disposition Available isolates sent to LAC PHL for PFGE 10

Results From September 2008 through May 2010 –25 CRKP specimens from 24 patients Prior to September 2008 there were no CRKP isolates identified 11

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13 Age (years) Number Range45-91 Median61.5 Mean65 Sex Female13 (54%) Male11 (46%) Outcome Recovered23 (96%) Died1 (4%) Acquisition (n=20) Community onset16 (80%) Hospital onset4 (20%) Results: Demographic and Clinical (n=24)

14 Admitted from (n=20 cases) SNF 13 (65%) Home 5 (25%) LTAC 2 (10%) Previous healthcare exposure – admitted from home 4 discharged from hospitals within previous 30 days 2 discharged from the same LTAC – hospitalizations did not overlap 3 had interaction with Facility A in previous 2 months 1 had no previous healthcare exposure Results: Previous Healthcare Exposure

Results: Disposition and Culture Site 15 Discharge to (n=20 cases) LTAC12 (60%) SNF7 (35%) Home4 (20%) Sites of CRKP isolation (n=25 specimens) Urine17 (65%) Wound4 (19%) Sputum4 (15%)

Lab Results: Pulsed Field Gel Electrophoresis (PFGE) (n=14) Eleven different strain genotypes –Four patients have > 3 band differences –Six patients have 1-3 band differences –Four patients share the same strain type (0 band difference) No common risks were identified Two HO cases tested had unique PFGE patterns 16

Lab Results: Antimicrobial Susceptibility Performed on 25 isolates from 24 patients, all resistant to: 1.Cefazolin 2.Ceftazidime 3.Ceftriaxone, 4.Cefepime 5.Ampicillin 6.Ampicillin/sulbactam 7.Piperacillin-tazobactam 8.Levofloxacin 9.Tobramycin 17

Lab Results: Antimicrobial Susceptibility Seventeen of 20 isolates (85%) susceptible to tigecycline Four of 25 isolates (16%) susceptible to gentamicin One of 21 (5%) isolates susceptible to amikacin One isolate was tested for colistin and was susceptible 18

Discussion Multiple CRKP strains appear in facility A –No common risks in those with same PFGE 80% of cases are defined as community onset Patients (96%) were admitted from other healthcare facilities around the community Patients (83%) were discharged to another healthcare facility Potential risks of inter-healthcare facility transmission 19

Discussion Potential risks of inter-healthcare facility transmission Perhaps represents a higher than expected prevalence in the county 20

Limitations Unable to trace back patient location beyond place of admit Inconsistent testing for susceptibility to carbapenems True prevalence in county unknown 21

Conclusion Cluster was not a hospital outbreak Undetected patients with CRKP pose considerable risk of transmission between healthcare facilities Heightened awareness is needed Emphasize transfer reporting between healthcare facilities CRKP surveillance by public health to monitor the prevalence/trends in the community and identify outbreaks 22

Acknowledgements May Mei-Sheng Riley L’Tanya English Patricia Marquez Sheena Chu Ron Jackson Laurene Mascola Robert Kim-Farley David Dassey Chart review team: –Kim Bryant –Merle Baron –Lorraine Sisneros –Sovirny Norng –Rosie Vasquez 23