Annual Survey of Laboratory Testing Practices for C. dif

Form Approved
OMB No. 0920-0978

Annual Survey of Laboratory Testing
Practices for C. difficile Infection

CDC’s Emerging Infections Program - Clostridioides difficile Infection Surveillance

Section 1: Laboratory Information
To be completed by surveillance officer
LABID#: _________________________

Completed By: _____________________________________
Date survey was completed: _____ /_____ /_____
Was this a new laboratory in 2021?
⃝ Yes
⃝ No
Year added to surveillance: ___________
Is this lab in another EIP site?
⃝ Yes
What state? ____________________
LabID in other EIP site: ____________________
⃝ No
Did this lab participate in surveillance in 2021?
⃝ Yes
⃝ No
How often did you receive line lists from this lab in 2021?
⃝ Whenever there is a positive case
⃝ Daily
⃝ Weekly
⃝ Monthly
⃝ Annually
⃝ Never
⃝ Other
Public reporting burden of this collection of information is estimated to average 19 minutes per response, including the time for reviewing instructions,
searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. An agency may
not conduct or sponsor, and a person is not required to respond to a collection of information unless it displays a currently valid OMB control number.
Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to
CDC/ATSDR Reports Clearance Officer; 1600 Clifton Road NE, MS D-74, Atlanta, Georgia 30329; ATTN: PRA (0920-0978).

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Specify: __________________________

How did you receive line lists from this lab in 2021?
⃝ Electronic laboratory reporting (e.g. HL7 messaging)
⃝ Fax
⃝ Email
⃝ Mail
⃝ Secure file transfer
⃝ Other
Specify: __________________________
Did you receive specimens from this lab in 2021?
⃝ Yes
⃝ No
Was this lab audited in 2021?
⃝ Yes, in person
⃝ Yes, not in person
⃝ No, not in catchment
⃝ No, not audited
Specify reason: ________________________
Is this a private, commercial lab (e.g. Quest or LabCorp)?
⃝ Yes
⃝ No
Types of facilities in your catchment area served by this lab in 2021 (select all that apply):
⃝ Hospitals
⃝ LTACHs
⃝ LTCFs
⃝ Outpatient facilities

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Section 2: Survey

To be completed by lab personnel
Instructions: This survey is intended to capture testing practices at your laboratory between January 1, 2021
and December 31, 2021.
Position of the staff who responded to the survey:
⃝ Laboratory Supervisor
⃝ Microbiology Supervisor
⃝ Other
Specify: ____________________

Offsite Testing
1. Did your laboratory ever send specimens off-site for Clostridioides difficile testing in 2021? (Choose one)
⃝ Always (no onsite testing performed)
LabID of Offsite Lab: ____________________
⃝ Regularly, as part of standard testing algorithm
LabID of Offsite Lab: ____________________
Which tests are done offsite, and at which point in the testing algorithm?
______________________________________
⃝ Not regularly, but when a test ordered by a physician cannot be performed onsite
Specify tests performed offsite: _________________________________
⃝ Never (All testing performed onsite)
⃝ Unknown
⃝ Other
Specify: __________________________

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Testing Routine for CDI
2. What type and order of testing was routinely used by your laboratory in standard testing for C. difficile on
December 31, 2021?
(Enter letter from choices below; choose only one option for each line of testing)
1st line of testing: ________ 2nd line of testing: ________ 3rd line of testing: ________
A. EIA Toxin A and B
B. EIA for Toxin A only
C. EIA for Toxin B only
D. EIA Antigen (GDH)
E. EIA Toxin A/B and Antigen (Simultaneous testing)
F. EIA Other
Specify other EIA type: __________________________
G. Nucleic Acid Amplification (e.g. PCR, Illumigene, Luminex, Biofire)
H. Culture
I. Cytotoxin
J. Other
Specify other test type: __________________________
K. No one routine test; clients can order from among several tests
Specify types: __________________________
L. None
2a. Which specimens were used during your 2nd line of testing? (Choose one)
⃝ Positive by the 1st line of testing
⃝ Negative by the 1st line of testing
⃝ Specimens with discordant results (e.g. EIA+/GDH- or GDH+/EIA-)
⃝ All specimens
⃝ Do not use 2nd line of testing
2b. Which specimens were used during your 3rd line of testing? (Choose one)
⃝ Positive by the 2nd line of testing
⃝ Negative by the 2nd line of testing
⃝ Specimens with discordant results (e.g. EIA+/GDH- or GDH+/EIA-)
⃝ All specimens
⃝ Do not use 3rd line of testing
2c. Did your laboratory perform any onsite testing for C. difficile outside of your normal testing algorithm in
2021?
⃝ No, all onsite testing is done according to the testing algorithm specified above
⃝ Yes, on physician request
Specify tests: __________________________

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⃝ Other
Specify: __________________________

Testing Kits for CDI
3a. Which EIA test kit was used by your laboratory in 2021? (Check all that apply)
□ Premier (Meridian) Toxins A & B
□ Premier (Meridian) Toxin A
□ Remel ProSpecT Toxins A & B
□ TechLab Toxins A & B
□ Inverness Medical/Wampole Toxins A & B QuikCheck
□ Inverness Medical/Wampole QuikCheck Complete (Toxins A & B and Antigen)
□ Antigen Testing
Specify antigen testing kit name/manufacturer: ____________________
□ Other
Specify other kit name/manufacturer: ____________________
□ N/A (Do not use EIA testing)
3b. Which Nucleic Acid Amplification test was used by your laboratory in 2021? (Check all that apply)
□ BD-GeneOhm C. difficile
□ BD MAX C. difficile
□ Cepheid Xpert C. difficile
□ Meridian Illumigene
□ Prodesse (Gen-Probe) Progastro CD
□ Luminex xTAG GPP
□ Biofire Filmarray GI Panel
□ Quidel AmpliVue C. difficile Assay
□ Great Basin Portrait Toxigenic C. difficile Assay
□ Nanosphere Verigene SP
□ Other
Specify other test: ____________________
□ N/A (Do not use nucleic acid amplification)

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Multiplex GI panels

4a. If your laboratory used a multiplexed molecular diagnostic (e.g., Biofire Filmarray GI Panel, Luminex xTAG
GPP) to test for several GI pathogens in 2021, did your laboratory suppress the C. difficile result so that
clinicians could not see it?
□ Yes, C. difficile result is always suppressed
□ Yes, C. difficile result is suppressed at clinician request
□ Yes, C. difficile result is suppressed but laboratory will release the result upon clinician request
□ Yes, C. difficile result is suppressed in certain situations
Specify: ______________
□ No, clinicians always see C. difficile result
□ N/A (Do not use multiplexed molecular diagnostic)
4b. If your laboratory used a multiplexed diagnostic in 2021 and the result was suppressed, where does the
suppression occur?
□ C. difficile result is suppressed at the multiplexed molecular diagnostic instrument level (the result is not
entered into the laboratory information management system (LIMS))
□ C. difficile result is suppressed at the laboratory information management system (LIMS) level
□ C. difficile result is suppressed somewhere else
Specify: ______________
□ N/A (Do not use multiplexed molecular diagnostic or the result is never suppressed)

Multistep Algorithm Testing for CDI

5a. If your laboratory used a nucleic acid amplification test (NAAT) (e.g., Cepheid Xpert C. difficile) as first line
testing followed by a toxin EIA test (whenever NAAT result is positive) in 2021, did your laboratory suppress
the positive NAAT result so that clinicians could not see it?
□ Yes, NAAT result is always suppressed when NAAT result is positive and confirmatory toxin EIA result is
negative
□ Yes, NAAT result is always suppressed but laboratory will release the positive NAAT result upon clinician
request
□ Yes, NAAT result is suppressed in certain situations
Specify: ______________
□ No, clinicians always see the positive NAAT result
□ N/A (Do not use this type of multistep algorithm testing)
5b. If your laboratory used NAAT as first line testing followed by confirmatory toxin EIA testing in 2021, and
both the NAAT and toxin EIA results were released to the clinician, did your laboratory provide any comments
to help the clinician interpret the test results (e.g., NAAT-positive only result might represent colonization,
etc.)?
□ Yes, laboratory provides comments to accompany the test results
o If yes, please specify the comments your laboratory uses to accompany the test results:
_______________________
□ No, laboratory does not provide comments to accompany the test results
□ The laboratory provides comments to accompany the test results in certain situations

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If yes, please specify the situations in which your laboratory provides comments and the
comments your laboratory uses to accompany the test results: _______________________
N/A (Do not use this type of multistep algorithm testing or NAAT test result is always suppressed)
o

□

Testing Codes
6. What are the LOINC or internal testing codes associated with the tests your lab used in 2021 (e.g. LOINC
codes 13957-6, 34713-8, or 54067-4)?
Specify: __________________________

CDI Testing Shortage and Capacity

7a. In 2021, did your laboratory experience any shortages in supplies, reagents, and/or test kits for
performing C. difficile testing (e.g., NAAT or EIA reagents, swabs)?
□ Yes
o If yes, please specify the dates during which the supply shortage occurred (provide approximate
dates if the exact dates are not known): __________
□ No
□ N/A (C. difficile testing was not routinely performed on onsite)
7b. If your laboratory experienced a supply shortage for C. difficile testing in 2021, how did the shortage affect
your laboratory’s ability to perform C. difficile testing? (Check all that apply)
□ We had to decrease the frequency of C. difficile testing during the shortage
□ We had to switch to an alternative method to test for C. difficile during the shortage
□ We were not able to perform any type of C. difficile testing during the shortage
□ We had to send all C. difficile testing offsite to another laboratory
□ The shortage did not affect our ability to perform C. difficile testing
□ Other, specify: _______________________________________
□ N/A (C. difficile testing was not routinely performed onsite)
7c. In 2021, did your laboratory experience a high demand for COVID-19 testing that limited the availability of
staff (e.g., reduced staffing or work time) or the use of equipment to perform C. difficile testing?
□ Yes
□ No
□ N/A (C. difficile testing and/or COVID-19 testing was not routinely performed onsite)

Laboratory Algorithm Changes
8. Did your lab testing algorithm for C. difficile change between January 1, 2021 and December 31, 2021?
⃝ Yes
What date did this change occur? ______ / ______ / ______

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⃝ No

8a. (If yes) What was the previous type and order of testing performed by your lab in 2021 before it changed
its testing algorithm?
(Enter letter from choices below; choose only one option for each line of testing)
1st line of testing: ________ 2nd line of testing: ________ 3rd line of testing: ________
A. EIA Toxin A and B
B. EIA for Toxin A only
C. EIA for Toxin B only
D. EIA Antigen (GDH)
E. EIA Toxin A/B and Antigen (Simultaneous testing)
F. EIA Other
Specify other EIA type: __________________________
G. Nucleic Acid Amplification (e.g. PCR, Illumigene, Luminex, Biofire)
H. Culture
I. Cytotoxin
J. Other
Specify other test type: __________________________
K. No one routine test; clients can order from among several tests
Specify types: __________________________
L. None
8b. Which specimens were used during your 2nd line of testing? (Choose one)
⃝ Positive by the 1st line of testing
⃝ Negative by the 1st line of testing
⃝ Specimens with discordant results (e.g. EIA +/GDH- or GDH+/EIA-)
⃝ All specimens
⃝ Do not use 2nd line of testing (go to question 6)
8c. Which specimens were used during your 3rd line of testing? (Choose one)
⃝ Positive by the 2nd line of testing
⃝ Negative by the 2nd line of testing
⃝ Specimens with discordant results (e.g. EIA+/GDH- or GDH+/EIA-)
⃝ All specimens
⃝ Do not use 3rd line of testing (go to question 6)

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OMB No. XXX-XXXX

Laboratory Policies
9. Did your lab have a policy to reject stool specimens for C. difficile testing in 2021? (Read all options. Check
all that apply)
□ Yes, when stools are formed (formed stools are defined as stools that do NOT take the shape of the
container)
□ Yes, if there is a stool specimen already positive within 24 hrs of a new stool specimen
□ Yes, if there is a stool specimen already positive within 48 hrs of a new stool specimen
□ Yes, if there is a stool specimen that tested negative for C. difficile within 48 hours of a new stool
specimen
□ Yes, will not accept more than one stool specimen in a 24 hr period
□ No rejection policy
□ Other rejection policies
Specify other rejection policy: __________________________
9a. Did your rejection policy for stool specimens change between January 1, 2021 and December 31, 2021?
⃝ Yes
What date did this change occur? ______ / ______ / ______
Specify changes: __________________________
⃝ No

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Testing Capacity
10. How many stool samples did you test for C. difficile each month in 2021?
Month
Stool samples tested
C. diff+ samples
January
February
March
April
May
June
July
August
September
October
November
December

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Appendix: Common C. difficile Test Kit Names and Manufactures
EIA Toxin A & B
Wampole* Toxin A/B Quik Chek
Techlab* C. difficile Toxin A/B II
BioMerieux Vidas C. difficile Toxin A/B
Meridian Immunocard Toxin A/B
Meridian Premier Toxin A/B
Remel Xpect C. difficile Toxin A/B
Remel ProSpecT Toxin A/B
EIA Antigen (GDH)
Wampole* C. difficile Chek-60
Wampole* C. difficile Quik Chek
Meridian Immunocard C. difficile
EIA Toxin A/B and Antigen (Simultaneous Testing)
Wampole* C. difficile Quik Chek Complete
Nucleic Acid Amplification
BD-GeneOhm C. difficile
Cepheid Xpert C. difficile
Great Basin Portrait Toxigenic C. difficile Assay
Luminex xTAG Gastrointestinal Pathogen Panel (xTAG GPP)
Meridian BioScience Illumigene
Nanosphere Verigene SP
Prodesse (Gen-Probe) Progastro CD
Quidel AmpliVue C. difficile Assay
EIA for Toxin B Only
Alere* C. difficile Toxin B

*Techlab, Inverness Medical, Alere, Wampole may be used interchangeably for these test kits