Cryptococcus DNA detection by PCR

single page view

General Information

Lab Name
Cryptococcus DNA detection by PCR
Lab Code
CRYDNA
Epic Ordering
Cryptococcus DNA detection by PCR
Description

Detection and differentiation of Cryptococcus neoformans and Cryptococcus gattii DNA.

Cryptococcus is a genus of fungus of which Cryptococcus neoformans is the most medically important species that primarily affects immunocompromised individuals. More recently genetic evidence for two distinct species, Cryptococcus neoformans and Cryptococcus gattii has been reported among strains of C. neoformans. C. gattii can infect even non-immunocompromised individuals and has been recognized as an emerging pathogen in US Northwest and adjoining Canadian state of British Columbia. It is therefore critical to correctly identify the exact type of C. neoformans to completely understand a given case of cryptococcal infection. Histology (mucicarmine stain), serology and culture are routinely used for a diagnosis. However, culture is not always successful or not possible in many cases where histology suggests the presence of Cryptococcus. PCR can be particularly useful in such cases to confirm or rule out a Cryptococcus neoformans infection and also determine the exact species i.e. C. neoformans or C. gattii.

Cryptococcus PCR detects Cryptococcus neoformans and Cryptococcus gattii with higher specificity and sensitivity than the broad-range fungal PCR. The analytical sensitivity is 1 genome per PCR reaction.

For more information on this test, to download a requisition form, and for a list of acceptable and unacceptable specimens, please refer to: Molecular Diagnosis Microbiology Section Website

References
Synonyms
Cryptococcus detection, Cryptococcus gattii identification, Cryptococcus gattii PCR, Cryptococcus gattii sequencing, Cryptococcus identification, Cryptococcus neoformans identification, Cryptococcus neoformans PCR, Cryptococcus neoformans sequencing, Cryptococcus sequencing, Filobasidiella bacillispora, Fungal sequencing, molecular Cryptococcus, Synonyms: Cryptococcus PCR, universal PCR
Components

Interpretation

Method

DNA extraction, nucleic acid purification, polymerase chain reaction (PCR), sequencing

Reference Range
See individual components
References
Guidelines

Ordering & Collection

Specimen Type
Tissue (Fresh frozen or paraffin-embedded), Fluid (see Acceptable Specimens for details)
Collection

Acceptable specimens are listed below. Please see this page for complete specimen collection and handling instructions.

Specimens should be collected into a DNA free container labeled with at least two identifiers.

Acceptable Specimens

  • Fresh frozen tissue
  • Fresh frozen fluid: any body fluid is acceptable if it is not listed under Unacceptable Specimens. See common examples below.
  • Formalin Fixed Paraffin-embedded tissues (FFPE, PET): blocks, scrolls, and unstained slides are acceptable
  • eSwabs and UTM (universal transport media)
  • Sodium polyanethol sulfonate (SPS, Wampole Isolator Tubes) acceptable with disclaimer

Common acceptable body fluid examples: cerebrospinal fluid, pleural fluid, pericardial fluid, urine, bronchial lavage, joint fluid, bone marrow, vitreous fluid, etc.

Additional Acceptable Specimens

  • Sputum

Unacceptable Specimens

  • Blood, serum, plasma, stool
  • No citrated or heparinized solutions
  • Tissues floating in formalin
  • Swab/fluid collected in tube containing agar
Handling Instructions

Fresh frozen tissue/fluid specimens should be submitted and maintained on dry ice.

Formalin Fixed Paraffin-embedded tissues (FFPE, PET) can be sent ambient or with ice packs during warmer summer months to prevent melting.


Optimal Quantity:

  • Fresh Tissue: 0.3-1.0 cm^3
  • Fluid: 0.2-1 mL
  • Formalin Fixed Paraffin-embedded Tissue (FFPE/PET): blocks are preferred and will be sent back to client upon completion of testing
  • Scrolls/unstained slides: cross-sectional area >1cm^2 send 10 sections of 10µm thickness, if <1cm^2 send 20 sections if available

Please note: We do not need a separate specimen aliquot for each test ordered. Only a single specimen aliquot or block of optimal quantity is necessary for performing multiple tests. If multiple aliquots or blocks of optimal quantity are sent, up to 2 will be pooled.

Quantity
requested: See Optimal Quantity above
minimum: Specimens below optimal quantity are acceptable for testing, however, diagnostic yield is generally proportional to specimen size.

Processing

Processing

UWMC/HMC – store and send specimen refrigerated and freeze specimens at -20°C upon arrival in UW-ML Microbiology. If specimen storage and transport will exceed 8 hours, freeze at -20°C.

Freeze specimens at -20°C upon arrival

Outside Laboratories: Freeze specimens in sterile containers at -20°C. Transport all specimens on dry ice.

Performance

LIS Dept Code
Micro Molecular Diag (MMD)
Performing Location(s)
UW-MT Microbiology, Molecular Diagnostics
206-520-4600

Clinical Lab, Room # NW177,
University of Washington Medical Center,
1959 NE Pacific street, Seattle, WA 98195

Frequency
Fresh frozen tissues/fluids result in 2-3 business days after receipt of specimen. Formalin Fixed Paraffin-embedded tissues result in 3-4 business days after receipt of specimen.
Available STAT?
No

Billing & Coding

CPT codes
87801
LOINC
81649-6
Interfaced Order Code
UOW4434