Mycology – Pneumocystis jirovecii pneumonia (PJP) Detection

Consistent with O. Reg. 671/92 of the French Language Services Act, laboratory testing information on this page is only available in English because it is scientific or technical in nature and is for use only by qualified health care providers and not by members of the public.

Background
This page provides direct microscopy testing information for Pneumocystis jirovecii, causative agent of Pneumocystis jirovecii pneumonia (PJP) at Public Health Ontario (PHO).

This page is for information specific to Pneumocystic jiroveci pneumonia (PJP) microscopy. For information regarding other testing options, refer to the following PHO webpages:

Updates

  • Added a table summary of possible test results and corresponding report comments.
  • Added specimen rejection criteria.

Testing Indications

Patients suspected of having Pneumocystis jirovecii pneumonia.

Acceptance/Rejection Criteria

Specimen collected using swab is not acceptable for testing.

Specimen Collection and Handling

Specimen Requirements

Test Requested Required Requisition(s) Specimen Type Minimum Volume Collection Kit

Pneumocytis jirovecii microscopy

Respiratory specimens including:

- bronchial washings
- bronchoalveolar lavage (BAL)
- sputum

1.0 mL

Sterile container

Submission and Collection Notes

1

Complete all fields of the requisition form, fields a-e are mandatory.

  1. Test(s) requests and indications for testing
  2. Specimen source (with details)
  3. Collection date and time
  4. Patient setting (eg. out-patient, in-patient, ICU, burn ward etc) - VERY important to note on the requisition
  5. Immune status – VERY important to note on the requisition if patient has had a transplant, has a haematological malignancy, or is otherwise immunocompromised (including burn wounds, diabetes etc) as this will impact work up and reporting practices
2

For clinical specimens, label the specimen container(s) with the patient’s first and last name, date of collection, and one other unique identifier such as the patient’s date of birth or Health Card Number. For additional information see: Criteria for Acceptance of Patient Specimens. Failure to provide this information may result in rejection or testing delay.

3

Submit a separate specimen and requisition for mycology testing, no matter what additional testing is requested, i.e. if fungal culture and TB or Legionella culture are required, separate specimens and requisitions should be submitted for each.

  1. Requests for both fungal culture and Pneumocystis jirovecii microscopy may be submitted using the same specimen and requisition.  

Limitations

Fungi-fluor microscopy only allows for visualization of the cyst form.

Storage and Transport

Specimens should be stored at 2- 8 °C following collection and shipped to PHO’s laboratory with ice pack as soon as possible. All clinical specimens must be shipped in accordance to the Transportation of Dangerous Good Act.

Requisitions and Kit Ordering

Test Frequency and Turnaround Time (TAT)

Pneumocytis jirovecii microscopy is performed daily, Monday to Friday at PHO’s Toronto laboratory.

For a specimen to be examined on the same day of receiving, it must be received at PHO’s Toronto laboratory by 14:00 EDT/EST during Mondays to Fridays; otherwise it will be examined on the next business day.

Turnaround time is up to 1 business day from receipt at PHO’s Toronto laboratory.

For weekends and holidays, specimen will be tested on next available business day.

STAT and Critical Specimens Testing

STAT testing available Monday-Friday if received at PHO’s Toronto laboratory by 14:00 EDT/EST.

STAT testing requests must be called to PHO Customer Service Centre at 1-877-604-4567 in advance of specimen receipt.

Test Methods

Pneumocystis jirovecii microscopy (fluorescent) is performed on smears prepared from specimens that are stained by Fungi-fluor® Kit.

During the microscopic examination, fluorescing Pneumocystis jirovecii cysts are visually detected. The Fungi-fluor® Kit is a non-specific stain used for the rapid detection of fungal elements from clinical specimens by fluorescent microscopy.

Negative microscopy results do not necessarily rule-out the possibility of Pneumocystis jirovecii infection.

Interpretation

The following table provides possible test results with associated interpretations:

Microscopic Result

Interpretation

Comments

Detected

Cysts of Pneumocystis jirovecii seen

 None.

Not detected

 No cysts of Pneumocystis jirovecii seen.

 None.

Inconclusive

Test results unable to determine presence/absence of Pneumocystis jirovecii cysts.

The test will be repeated internally, if enough specimen remains, prior to issuing a report.

Final report may indicate to resubmit specimen.

Reporting

Results are reported to the physician, authorized health care provider (General O. Reg 45/22, s.18) or submitter as indicated on the requisition.

References

  1. Clinical and Laboratory Standards Institute (CLSI). Principles and Procedures for Detection and Culture of Fungi in Clinical Specimens. 2nd ed. CLSI guideline M54 (ISBN 978-1-68440-098-0 {Print}; ISBN 978-1-68440-099-7 {Electronic}). Clinical and Laboratory Standards Institute; 2021
  2. Hazen, K., Howell, S.A.. Mycology and antifungal susceptibility testing. In: Leber, A.M. Editor. Clinical Microbiology Procedures Handbook. 4th ed. Washington, D.C.; ASM Press; 2016.
  3. de Hoog, G.S., Guarro, J., Gene, J., Ahmed, S.A., Al-Hatmi, A.M.S., Figueras, M.J., Vitale, R.G.. Atlas of Clinical Fungi. 4th ed. Hilversum; Foundation Atlas of Clinical Fungi; 2020.
  4. Fungi-Fluor Kit Technical Data Sheet #482. Polysciences Inc. 
Updated 2 Dec 2024