Pneumocystis jirovecii, Real-Time PCR
Test Mnemonic
PJPCR
CPT Codes
- 87798 - QTY (1)
LOINC ®
49441-9
Aliases
- PCP
- PCP stain
- Pneumocystis carinii
- Toluidine Blue Stain
- PJP
- PJPCR
Includes
- Detection of Pneumocystis jirovecii by PCR
Performing Laboratory
Cleveland Clinic Laboratories
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 2 mL | Bronch (BAL) | Sterile container | Refrigerated | Collect and submit the specimen in a sterile container (ie. Oracle #1012787, Covidien #2200SA). If aliquoting is necessary, sterile tubes must be used. | |
| 2 mL | Sputum | Sterile container | Refrigerated | Collect and submit the specimen in a sterile container (ie. Oracle #1012787, Covidien #2200SA). If aliquoting is necessary, sterile tubes must be used. | |
| N/A | Tissue, lung | Sterile container | Refrigerated | Collect and submit the specimen in a sterile container (ie. Oracle #1012787, Covidien #2200SA). If aliquoting is necessary, sterile tubes must be used. |
Alternate Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 2 mL | Washings, bronch | Sterile container | Collect and submit the specimen in a sterile container (ie. Oracle #1012787, Covidien #2200SA). If aliquoting is necessary, sterile tubes must be used. | ||
| 2 mL | Aspirate, tracheal | Sterile container | Collect and submit the specimen in a sterile container (ie. Oracle #1012787, Covidien #2200SA). If aliquoting is necessary, sterile tubes must be used. |
Minimum Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 1 mL |
Stability
| Environmental Condition | Description |
|---|---|
| Ambient | 24 hours |
| Refrigerated | 7 days |
| Frozen | 30 days |
Days Performed
6 days per week
Turnaround Time
3 days
Methodology
| Name | Description |
|---|---|
| Polymerase Chain Reaction (PCR) |
Reference Range
| Pneumocystis jirovecii DNA | |||||
|---|---|---|---|---|---|
| Sex | Age From | Age To | Type | Range | Range Unit |
| Pneumocystis jirovecii Not Detected by PCR |
Special Info
Test performed Monday through Friday and Saturday or Sunday.
Clinical Info
Pneumocystis jirovecii is an atypical fungus that causes Pneumocystis pneumonia (PCP) in patients with a compromised immune system. Transplant recipients and those with poorly controlled HIV are at highest risk, but those receiving chemotherapy for malignant diseases and others with immunosuppression may also develop the disease. PCP is an important cause of morbidity and mortality in immunocompromised patients. The diagnosis of PCP is a challenge since the microorganism does not grow in conventional culture, and direct microscopy methods have suboptimal sensitivity. Molecular methods of detection are preferred due to their superior sensitivity, but these assays can be positive in colonized individuals without overt clinical disease. This updated Pneumocystis jirovecii real-time polymerase chain reaction (RT-PCR) assay targets the mitochondrial large ribosomal subunit gene (mtLSU rRNA), which is present in multiple copies per organism, to optimize assay sensitivity.
Clinical Limitation
This assay is intended for use as a lab-developed test for the detection of Pneumocystis jirovecii DNA from lower respiratory specimens. It is meant to be used as an aid in the diagnosis of Pneumocystis pneumonia (PCP), in conjunction with other clinical and laboratory information. The test should only be ordered in individuals suspected to have PCP, as the assay has been described to be positive in some colonized individuals without presenting features of PCP disease. Although a negative result does not entirely rule out the presence of Pneumocystis, the negative predictive value of this test is very high. Test results should be interpreted alongside clinical history, imaging findings, and ancillary laboratory data if available.