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Test Order
Test Order
Ameba Identification (Acanthamoeba, Balamuthia, Naegleria)
CDC-10286
Synonym(s)
Free-living ameba, Acanthamoeba, Balamuthia, Naegleria fowleri, primary amebic meningoencephalitis (PAM), granulomatous amebic encephalitis (GAE), Acanthamoeba keratitis (AK), brain-eating ameba
CDC Pre-Approval Needed
Supplemental Information Required
Provide the following information: history of present illness, exposure history, past medical history, treatment history, CSF results, imaging results. Available images can be submitted for preliminary morphological diagnosis prior to submitting specimen for molecular identification. Contact dpdx@cdc.gov for more information about submitting images.
Supplemental Form
Not Applicable
Performed on Specimens from
Human and Animal
Acceptable Sample/ Specimen Type for Testing
Fresh, unfixed tissue, cerebrospinal fluid (CSF), biopsy specimen, and deep corneal scrapings.
Minimum Volume Required
<0.2 mL fluids (preferred 1 mL); 0.1 g tissue (preferred 0.2 g); 5-10 mm corneal scraping.</
Collection, Storage, and Preservation of Specimen Prior to Shipping
CSF and fresh, unfixed tissue, and corneal scraping should be kept and shipped at (a) refrigerated temperature (2-8°C) within 7 days, or (b) frozen (-20°C or lower, in absence of PBS buffer) within 60 days.
Transport Medium
For deep scraping and brain or skin biopsy materials, transport in a small volume of 0.5x phosphate-buffered saline (PBS) to prevent dryness for refrigerated temperature shipment with ice-packs. However, addition of 0.5x PBS is not needed if specimen is stored and shipped frozen
Unfixed deep corneal scraping and brain or skin biopsy materials for identification of free-living ameba are usually very small and may dry if they are not stored in proper fluid such as 0.5x PBS. However, frozen tissue can be shipped frozen on dry-ice without adding 0.5x PBS.
Unfixed deep corneal scraping and brain or skin biopsy materials for identification of free-living ameba are usually very small and may dry if they are not stored in proper fluid such as 0.5x PBS. However, frozen tissue can be shipped frozen on dry-ice without adding 0.5x PBS.
Specimen Labeling
Test subject to CLIA regulations and requires two primary patient identifiers (e.g., patient first and last name, date of birth, unique patient identifier from time of collection, such as medical record number) on the specimen container and on the test requisition.
Shipping Instructions which Include Specimen Handling Requirements
CDC does not accept routine shipments on weekends or holidays. Please make sure packages arrive Monday – Friday.
Ship To:
[Insert CDC Point of Contact]
Centers for Disease Control and Prevention
RDSB/STATT Unit 54
1600 Clifton Road, NE
Atlanta, GA 30329
[Insert CDC Point of Contact’s Telephone Number]
All samples must be shipped in accordance with all applicable local, state and federal regulations. Upon shipment, submitter should send an email to the CDC POC providing shipping company, shipped date and package tracking number.
Ship To:
[Insert CDC Point of Contact]
Centers for Disease Control and Prevention
RDSB/STATT Unit 54
1600 Clifton Road, NE
Atlanta, GA 30329
[Insert CDC Point of Contact’s Telephone Number]
All samples must be shipped in accordance with all applicable local, state and federal regulations. Upon shipment, submitter should send an email to the CDC POC providing shipping company, shipped date and package tracking number.
Methodology
Real-time polymerase chain reaction (PCR).
Turnaround Time
7 Days
Interferences & Limitations
For molecular detection, CSF is the preferred specimen type for N. fowleri only, and it is NOT the preferred specimen type for Acanthamoeba or Balamuthia detection. A negative CSF test result does not completely rule out infection with Acanthamoeba or Balamuthia. Fresh or frozen (unfixed) tissue specimens are preferred for Balamuthia or Acanthamoeba detection. Formalin-fixed specimens are not acceptable for molecular studies as formalin fixation may cause DNA degradation.
Regarding testing of formalin-fixed specimens see Test Order CDC-10365 (Pathologic Evaluation of Tissues for Possible Infectious Etiologies) and contact pathology@cdc.gov.
Regarding testing of formalin-fixed specimens see Test Order CDC-10365 (Pathologic Evaluation of Tissues for Possible Infectious Etiologies) and contact pathology@cdc.gov.
Additional Information
For 24/7 diagnostic assistance, specimen collection guidance, shipping instructions, and treatment recommendations, contact the CDC Emergency Operations Center at (770) 488-7100.
CDC Points of Contact
Version
2.7
Content Credential