What the HIV serology requisition is for
The form orders HIV diagnostic serology, HIV-1/-2 PCR, or both, at Public Health Ontario’s laboratory. Serology is the screening and diagnostic test. PCR detects viral RNA and is reserved for situations where antibodies can’t answer the question yet, such as an infant or a patient in the window period.
It is often confused with two other PHO forms. Prenatal HIV screening can go on the Prenatal Screening Requisition, and resistance testing and tropism for a patient already diagnosed go on the HIV-1 Drug Resistance and Genotype requisition.
Who completes it
The ordering health care provider completes the whole form. You must be authorized to order laboratory tests in Ontario. The licence number field takes your OHIP billing number, CPSO number or other college registration number, and clinics with rotating providers should name the attending provider.
How to fill in the requisition
Submitter / Health Care Provider (HCP) Information
Give your name, licence number, address, telephone and fax, and complete the Copy to fields for any other provider who needs the result. PHO advises against relying on pre-populated details without checking them.
Patient Information
Use the names as they appear on the health card, and make sure they match the specimen label, or testing is cancelled. Don’t leave the health card number blank. Country of birth is starred on the form because submitters often miss it: write “not available” if it’s unknown. Tick every race and ethnicity box that applies.
Specimen Information and Test(s) Requested
Serum in a serum separator tube is the standard for serology. PCR also accepts EDTA plasma and dried blood spots, and plasma with any anticoagulant other than EDTA is rejected. Record the collection date. Other specimen types need PHO microbiologist approval before you send them.
Testing Indication(s) / Criteria and Risk Factors
The indication is mandatory. Choose from routine, prenatal, PrEP, post-exposure prophylaxis, infant diagnosis, symptoms of acute or advanced infection, sexual assault, visa or immigration, a self-test result, or a known positive being retested. Tick every risk factor that applies.
Most Recent HIV Laboratory Test Result
Record the last laboratory HIV test, not a point-of-care result, and whether it was done in or outside Ontario. If PHO did it, add the previous sample number.
Common reasons it’s rejected or delayed
- No testing indication.
- A blank country of birth or health card number.
- Patient details on the tube that don’t match the requisition.
- PCR requested for routine screening or for a pregnant patient with no prenatal screening.
- Haemolysed, lipemic or contaminated serum, or plasma collected with the wrong anticoagulant.
- Specimens sent for donor screening, which PHO doesn’t offer.
Submitting and who pays
Send the specimen with the requisition to PHO’s laboratory. Results go to the provider named on the requisition, and positive diagnostic results are reported to the medical officer of health where the patient lives. PHO only performs insured services under Ontario’s Health Insurance Act, so the patient isn’t charged.