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MDL Test Order Neisseria gonorrhoeae (GC) Antibiotic Susceptibility Testing (AST) for Azithromycin, Ceftriaxone, and Cefixime

microbial DISEASES LABORATORY BRANCH

Test Name

Neisseria gonorrhoeae (GC) Antibiotic Susceptibility Testing (AST) for Azithromycin, Ceftriaxone, and Cefixime

Test Methodology	Neisseria gonorrhoeae (GC) Antibiotic Susceptibility Testing (AST) for Azithromycin, Ceftriaxone, and Cefixime
Reflex Testing Criteria	bioMérieux Etest Gradient Strip (“GC Etest”)
Pre-Approval Required	Pre-Approval for isolates meeting one of following is not required: N. gonorrhoeae isolates with decreased susceptibility to cefixime (MIC ≥0.25 µg/mL), ceftriaxone (MIC ≥0.125 µg/mL), or azithromycin (MIC >16.0 µg/mL). N. gonorrhoeae isolates from suspected treatment failures (Clinical Guidelines for Gonorrhea Treatment and Management of Suspected Treatment Failure PDF) and isolated from sites, including but not limited to urethra, endocervix/vagina, rectum, pharynx, blood, synovial fluid, and eye. N. gonorrhoeae isolates from disseminated gonococcal infections (DGI). N. gonorrhoeae isolates from ocular infections Pre-approval for other N. gonorrhoeae isolates is required. Please contact STD program at stdcb_argc@cdph.ca.gov.
Supplemental Information and Required Form(s)	Submitters can use one of the following methods to access the submittal form: MDL Lab Web Portal (LWP) (Preferred) or MDL barcode submittal form at MDL Submission Instructions and Forms. On the MDL General Submission form, select Form Antimicrobial Susceptibility Testing -AST: MDL General Electronic Submission Form (PDF) The MDL General Electronic Submission Form should be downloaded and opened using a pdf viewer. To download, right-click the link and select "Save link as." If you are unable to open the Form using a pdf viewer, please contact MDL at 510-412-3700 or MDL.Submissions@CDPH.ca.gov. Instructions on completing the form can be found at the following links: MDL Form AST - Instructions Gradient Strip (GC Etest) Neisseria gonorrhoeae Antimicrobial Susceptibility Testing Services Frequently Asked Questions (FAQ)
Required Specimen/ Sample Type(s)	Pure, fresh culture of N. gonorrhoeae submitted on chocolate or modified Thayer Martin media supporting growth of N. gonorrhoeae.
Minimum Volume Required	Not Applicable
Specimen Stability	Prepare culture for transportation: First, obtain fresh culture by growing a pure N. gonorrhoeae isolate at 35°C in 5% CO2 on suitable media for gonorrhea (such as chocolate agar or modified Thayer-Martin) for 24-48 hours, until obtain visible growth. Then, prepare and submit the culture fresh (24-72 hr) at time of shipping. Three options are recommended. To ship using an agar slant: Heavily inoculate a chocolate (or other suitable media for GC) slant with fresh growth. Incubate at 35°C with 5% CO2 until you see visible growth (18 – 24 hours is ideal). Then close cap tightly and ship at ambient temperature. To ship using an agar plate: Heavily inoculate a chocolate (or other suitable media for GC) plate with fresh growth. Incubate at 35°C with 5% CO2 until you see visible growth (18 – 24 hours is ideal). Then seal the plate lid tightly with parafilm and place the plate in zip lock biohazard bag and ship at ambient temperature. To ship using a frozen cryotube with TSB and 15% glycerol: Heavily inoculate a cryotube with fresh growth. Immediately place in a -60°C or lower freezer. Once the isolate is fully frozen, ship the isolate on dry ice. Refer to ‘Specimen preparation for transport’ instructions in Disseminated Gonococcal Infection (DGI) Guidance for Laboratories for details.
Rejection Criteria	Isolate submissions with insufficient or conflicting labelling Broken or leaking samples Samples with insufficient quantities or growth Isolates that are too old or non-viable Specimen/sample types not meeting acceptance criteria (see FAQ), if no prior approval was received Mixed cultures Primary patient samples
Storage/Transport Conditions	Culture isolates may be shipped at ambient temperature or frozen in TSB with 15% glycerol on dry ice.
Transport Medium, if applicable	Not Applicable
Specimen Labeling	Two identifiers, including patient full name, and at least one other identifier (specimen accession number, date of birth, medical record number); date and time of collection as noted for specific tests, if applicable.
Shipping Instructions and Specimen Handling Requirements	Ship isolates grown on media that supports N. gonorrhoeae at ambient temperature or ship cultures frozen in TSB with 15% glycerol on dry ice. Follow the appropriate DOT/IATA approved shipping procedures. Ship to: California Department of Public Health Microbial Diseases Laboratory ATTN: Bacterial Diseases Section 850 Marina Bay Parkway, Specimen Receiving Room B106 Richmond, CA 94804
Specimen Collection Instructions, if applicable	Only pure, live cultures of N. gonorrhoeae are acceptable for testing at MDL. Primary clinical specimens for culture isolation are not accepted by MDL at this time. Primary clinical specimens from suspected treatment failures may be tested via the ARLN regional laboratory in Washington state. Contact stdcb_argc@cdph.ca.gov or MDL.Submissions@CDPH.ca.gov for submission instructions.
Turnaround Time	12 calendar days Expedited testing may be available upon request.
Interferences & Limitations	Pure culture isolates must be viable for testing.
Reference Range	Not Applicable
Additional Information	Gradient Strip (GC Etest) Neisseria gonorrhoeae Antimicrobial Susceptibility Testing Services Frequently Asked Questions (FAQ)
MDL Point of Contact	For more information on the GC Etest and submission criteria o instructions, please email MDL.Submissions@CDPH.ca.gov or call MDL Bacterial Diseases Section at (510) 412-3903

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