Post Transfusion Purpura (PTP)

Blood Transfusion

Notes

Post-transfusion purpura (PTP) is a delayed adverse reaction to a blood or platelet transfusion that occurs when the body has produced antibodies to the donor transfused platelet antigens. These antibodies destroy the patient's platelets leading to a rapid decline in platelet count. PTP usually presents 5–12 days after transfusion.

• Requires Consultant Haematologist approval
• Histocompatibility & Immunogenetics Diagnostic Laboratory Form 3D required to request this test (form available from Transfusion laboratory or available using the link below)
• Test performed at NHSBT, Filton, Bristol
• The following factors are known to significantly affect the performance of the examination or the interpretation of the results: lipaemia, sample clotted (if EDTA), haemolysed. Any sample displaying these factors cannot be processed and will be rejected

H&I Request Form (3D) - Platelet Immunology

Sample Requirements

• EDTA tube - 6mL

• Serum tube - 6mL

Required Information

Sample and request form must be labelled correctly with 4 points of reference:

1. Forename
2. Surname
3. Date of birth
4. NHS No.

The sample tube(s) must be signed and dated by the person taking the blood.

The NHSBT may decline to test inadequately labelled samples.

For further information on specimen labelling refer to the H&I 3D Platelet Immunology request form

Turnaround times

7 working days