HC
Memo
1500 Forest Glen Road
Silver Spring, MD
20910-1484
Phone: (301) 754-7000 www.holycrosshealth.org
TO: All Holy Cross Hospital Affiliated Physicians
FROM: Pablo Gutman, M D \ ^ '
Medical Director, Microbiology Laboratory > ^
DATE: February 15, 2012 ^~~~-^<\
SUBJECT: Clostridium difficile Disease (CDI) Panel
Effective March 19, 2012 the Microbiology laboratory will implement a new algorithm for Clostridium difficile disease testing (See attachment). The laboratory will perform antigen detection testing on all stools submitted for CDI to determine the presence or absence of Clostridium difficile in the stool.
Reflexive toxin testing will be performed on all specimens with a positive antigen result using enzyme immunoassay (EIA) and/or real time polymerase chain reaction
(RT-PCR) methods. in addition, a fecal lactoferrin test will be performed to determine the presence or absence of inflammation t o assist in the differentiation of carrier states and active infection.
Test
Normal value
C. difficile Antigen variable
Test
Results positive c. difficile antigen detected
Negative C. difficile antigen NOT detected invalid The presence or absence of C. difficile antigen cannot be determined
C. difficile Toxin
Negative
Toxigenic C. difficile detected
Toxigenic C. difficile
NOT detected
The presence or absence of toxigenic C.
difficile cannot be determined
Fecal Lactoferrin
Negative
Fecal lactoferrin detected
Fecal lactoferrin
NOT detected
The presence or absence of fecal lactoferrin cannot be determined
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HC
1500 Forest Glen Road
Silver Spring, MD
20910-1484
Phone: (301) 754-7000 www.hoiycrossheaith.org
• Testing should be limited to patients with _> 3 diarrheal (unformed) stools in a 24 hour period, unless ileus (obstruction) is suspected.
• Patients may carry toxigenic Clostridium difficile months after a positive test with clinical cure. Test of cure is not recommended.
• Repeat testing after a positive test is recommended only in instances of improvement with therapy followed by clinical relapse after the completion of treatment.
• Repeat testing during the same episode of diarrhea will not be performed.
• Neonates may be colonized with toxigenic Clostridium difficile. Consultation with an infectious Disease physician is recommended prior to requesting this testing for this patient population.
• if c. difficile disease is strongly suspected after a negative test result, performance of toxin detection assays after toxigenic culture may be required. At present culture methods are available through outside reference laboratories.
Thank you for allowing us to help you serve your patients. Please contact the laboratory director, Jay Marchwinski (301-754-7321), or myself if you have any questions or concerns regarding our laboratory's practices or service to your patients.
References:
1. Cohen SH, Gerding DN, Johnson s, Kelly CP, LOO VG, McDonald LC, Pepin J, Wilcox M H .
Clinical practice guidelines for Clostridium difficile infection in adults:
2010 update by the society for Healthcare Epidemiology of America (SHEA) and the
infectious Diseases society of America (IDSA), infection Control and Hospital
Epidemiology. 2010 31(5):43155.
2. Swindells J, Brenwald N, Reading N, Oppenheim B., "Evaluation of diagnostic tests for Clostridium difficile infection", Journal of Clinical Microbiology. 2010
February48(2):6068.
cc: S. Mitchell, MD
B. Eig, MD j . Marchwinski
M. Mohyla, RN, CIC
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HC
Holy Cross Hospital
Microbiology Laboratory
C. difficile Disease
Test Algorithm
C. difficile Antigen
Screen
Positive
1500 Forest Glen Road
Silver Spring, MD
20910-1484
Phone:(301)754-7000 www.holycrosshealth.org
C. difficile"
NOT detected
Fecal Lactoferin
Toxigenic
C difficile
NOT detected
( Possible carrier A f Inflammatory \
I state ) ^diarrheal disease/
Holy C r o s s . E x p e r t s in M e d i c i n e , S p e c i a l i s t s in C a r i n g .
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