HIV 1 and 2 antibody and p24 antigen screen (Dried Blood Spot) (Virology)

This service is designed for those patients on whom it is difficult to obtain venous blood, especially for intra venous drug users.

Contact the laboratory for supply of postal packs containing all necessary items for using this service.

Paediatric/infant packs are available on request

General information

Collection container (including preservatives): Envelope with dessicant

Specimen type: Dried blood spot card

Collection:

1) Disposable gloves should be worn for the whole procedure to protect you and the sample from degradation.

2) Ensure the patient's hands are clean. If the hands are cold ask the patient to rub them together. It is important the puncture site is warm.

3) Identify and clean the puncture site:

• Use one of the outer three fingers
• Avoid finger pad and nail bed
• Clean site with alcohol wipe, then dry

4) Break the seal by twisting.

5) Hold the lancet with two fingers and place at the puncture site.

6) Gently apply pressure until the lancet is activated. A click sound will be heard when this has happened.

7) Safely discard the lancet in a sharps container.

8) Spot blood onto each of the 5 circles on the card. To ensure enough blood flow:

• Hold the puncture site down
• Apply intermittent pressure. Avoid strong repetitive pressure (milking), it can damage the area

Note: Fill each circle with blood. Failure to do so may reduce the sensitivity of the screening tests.

9) Leave the card to dry for a minimum of 30 minutes.

10) Place card along with one bag of desiccant in the plastic carrier attached to the request form.

11) Ensure the required details have been entered on both the request form and the dried blood spot card. Place the request card in the envelope provided and send back to the laboratory.

Specimen transport: No special needs

Minimum volume of sample: 7mm diameter blood spot

Special precautions: Ensure blood spot has dried and submit with dessicant pouch enclosed

Laboratory information

Measurement units: Not applicable

Biological reference units: Not applicable

Turn round time for provisional result (working days): 4 days

Turn round time to final result (working days): 5 days

Clinical information

Clinical decision points: Not applicable

Factors known to significantly affect the results: Spots too small, not all spots filled with blood