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HelpTest Code KNSRP Klebsiella pneumoniae Carbapenemase (blaKPC) and New Delhi Metallo-beta-Lactamase (blaNDM) Surveillance, PCR, Varies
Reporting Name
KPC and NDM Surveillance PCRUseful For
Identifying carriers of carbapenem-resistant Gram-negative bacilli harboring Klebsiella pneumoniae carbapenemase or New Delhi metallo-beta-lactamase genes
Method Name
Real-Time Polymerase Chain Reaction (PCR) using LightCycler and Fluorescent Resonance Energy Transfer (FRET)
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
VariesSpecimen Required
Ordering Guidance
This assay should be used for surveillance testing on perirectal/rectal/perianal, anal swabs, or fecal specimens only. If testing isolates from culture, order KPNRP / KPC (blaKPC) and NDM (blaNDM) in Gram-Negative Bacilli, Molecular Detection, PCR, Varies.
Necessary Information
Specimen source is required.
Specimen Required
The high sensitivity of amplification by polymerase chain reaction requires the specimen to be processed in an environment in which contamination of the specimen by Klebsiella pneumoniae carbapenemase or New Delhi metallo-beta-lactamase DNA is not likely.
Submit only 1 of the following specimens:
Preferred:
Specimen Type: Perianal, anal, perirectal, rectal
Supplies: Culturette (BBL Culture Swab) (T092)
Container/Tube: Culture transport swab (Dacron or rayon swab with aluminum or plastic shaft with either Stuart or Amies liquid medium)
Specimen Volume: Swab
Specimen Stability Information: Refrigerated (preferred)/Frozen
Acceptable:
Specimen Type: Preserved feces
Supplies: Culture and Sensitivity Stool Transport Vial (T058)
Container/Tube: Commercially available transport system specific for recovery of enteric pathogens from fecal specimens (15 mL of nonnutritive transport medium containing phenol red as a pH indicator, either Cary-Blair or Para-Pak C and S vial)
Specimen Volume: Representative portion of feces
Collection Instructions:
1. Collect fresh feces and submit 1 gram or 5 mL in container with transport medium.
2. Place feces in preservative within 2 hours of collection.
Specimen Stability Information: Ambient (preferred)/Refrigerated
Specimen Minimum Volume
See Specimen Required
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Varies | Varies | ||
Reject Due To
| E-swab Calcium alginate swab Cotton-tipped swab Swab sent in gel transport medium Swab sent in viral or universal transport medium |
Reject |
Reference Values
Negative
Day(s) Performed
Monday through Friday
CPT Code Information
87798 x 2
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| KNSRP | KPC and NDM Surveillance PCR | 85502-3 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| SRCKP | Specimen source | 31208-2 |
| 35165 | KPC PCR | 49617-4 |
| 35166 | NDM PCR | 73982-1 |
Test Classification
This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.Clinical Information
The Centers for Disease Control and Prevention recommends active surveillance to detect unrecognized colonized patients who may be a potential source for carbapenem-resistant (drug-resistant) Enterobacteriaceae (CRE) transmission. Such surveillance testing may be focused in certain high-risk settings or patient groups (eg, intensive care units, long-term acute care, patients transferred from areas or facilities with high CRE prevalence) or by infection control to investigate an outbreak. Nonsusceptibility to carbapenems in gram-negative bacilli by means of the enzyme Klebsiella pneumoniae carbapenemase (KPC) or New Delhi metallo-beta-lactamase (NDM) is becoming more common. The genes blaKPC and blaNDM encode KPC and NDM enzyme production, respectively. Polymerase chain reaction testing is a sensitive, specific, and rapid means identifying patients colonized by CRE-harboring blaKPC or blaNDM.
Interpretation
This polymerase chain reaction (PCR) test detects and differentiates blaKPC and blaNDM in surveillance specimens (perirectal/rectal/perianal/anal swabs or feces). A positive Klebsiella pneumoniae carbapenemase (KPC) and/or New Delhi metallo-beta-lactamase (NDM) PCR result indicates that the patient is colonized by a Gram-negative bacillus (or Gram-negative bacilli) harboring a carbapenemase gene, blaKPC and/or blaNDM, respectively.
A negative result indicates the absence of detectable DNA.
Cautions
False-negative results may occur due to inhibition of polymerase chain reaction, sequence variability underlying primers and probes, or the presence of the blaKPC or blaNDM genes in quantities lower than the limit of detection of the assay.
Supportive Data
The performance of this assay was demonstrated by spiking perirectal swab and stool specimens (30 positive and 30 negative for each specimen type) with quantified heat-killed bacteria carrying blaNDM or blaKPC. The sensitivity and specificity in spiked stool specimens were 100% for both blaNDM and blaKPC; for perirectal swabs the sensitivity and specificity were 93% and 100%, respectively, for blaKPC and 100% and 100%, respectively, for blaNDM. The assay had the following limits of detection in perirectal swabs and stool, respectively: blaKPC, 9 and 90 CFU/microliter and blaNDM 1.9 and 1.9 CFU/microliter.
In addition, 33 rectal swab specimens previously characterized as containing isolates of Klebsiella pneumoniae carbapenemase (KPC) polymerase chain reaction (PCR)-positive Enterobacteriaceae using the method of Lolans(1) were tested by the Mayo Clinic KPC and New Delhi metallo-beta-lactamase (NDM) PCR assay. There was complete agreement with the expected results.
Clinical Reference
1. Lolans K, Calvert K, Won S, Clark J, Hayden MK: Direct ertapenem disk screening method for identification of KPC-producing Klebsiella pneumoniae and Escherichia coli in surveillance swab specimens J Clin Microbiol. 2010;48:836-841. doi: 10.1128/JCM.01988-09.
2. New carbapenem-resistant Enterobacteriaceae warrant additional action by healthcare providers. Centers for Disease Control and Prevention Health Alert Network, February 14, 2013
3. Vasoo S, Cunningham SA, Kohner PC, et al: Comparison of a direct and broth-enriched PCR, HardyCHROM ESBL and the CDC method for detection of Klebsiella pneumoniae carbapenemase carriage in surveillance rectal swabs. Abstracts of the Ninth International Symposium on Antimicrobial Agents and Resistance, Kuala Lumpur, Malaysia. March 13-15, 2013
Method Description
Perirectal swabs are processed in neutralization buffer tubes and organisms are lysed to release their genomic material. Stool specimens undergo DNA extraction prior to polymerase chain reaction (PCR). This assay amplifies and detects a specific portion of the genes encoding the Klebsiella pneumoniae carbapenemase (KPC) and New Delhi metallo-beta-lactamase (NDM) enzymes. The LightCycler instrument amplifies and monitors target nucleic acid sequences by fluorescence during PCR cycling. This is an automated PCR system that can rapidly detect amplified product development through stringent air-controlled temperature cycling and capillary cuvettes. The detection of amplified products is based on the fluorescent-resonance energy transfer (FRET) principle. For FRET product detection, a hybridization probe with a donor fluorophore, fluorescein, on the 3' end is excited by an external light source, which emits light that is absorbed by a second hybridization probed with an acceptor fluorophore LC-Led 610 (blaKPC specific) and LC-red 670 (blaNDM specific), on the 5' end. The acceptor fluorophore then emits a light of a different wavelength that can be measured with a signal that is proportional to the amount of specific PCR product. The detection process is completed in less than 1 hour using a closed tube system.(Cunningham SA, Noorie T, Meunier D, Woodford N, Patel R: Rapid and simultaneous detection of genes encoding Klebsiella pneumoniae carbapenemase (blaKPC) and New Delhi metallo-beta-lactamase (blaNDM) in Gram-negative bacilli. J Clin Microbiol 2013;51:66-69. doi: 10.1128/JCM.03062-12.)
Report Available
1 to 4 daysSpecimen Retention Time
3 days if received in a swab transport, 7 days if received in C and S vialNY State Approved
YesForms
If not ordering electronically, complete, print, and send a Microbiology Test Request (T244) with the specimen.
Secondary ID
62195Highlights
Detects Klebsiella pneumoniae carbapenemase (KPC)and New Delhi metallo-beta-lactamase (NDM) DNA (associated with antimicrobial resistance) in perirectal/rectal/perianal/anal swabs or fecal specimens.