What information should be included on a pathology form when ordering ABO (Blood Group) titres, including immunoglobulin M (IgM) and immunoglobulin G (IgG) titres, for a patient with a history of transfusions or pregnancies?

What to Write on Pathology Form for ABO Titres

When ordering ABO titres, you must document the patient's transfusion and pregnancy history within the past 3 months on the pathology request form, as this directly impacts sample validity and testing urgency. 1

Essential Patient Identifiers

The pathology form must include these minimum identifiers to prevent wrong-blood-in-tube events and ABO incompatibility risks 1:

• Surname and forename 1
• Date of birth 1
• Hospital unique identification number or NHS number (or equivalent) 1
• Patient identification band confirmation (document that the patient is wearing one) 1

Critical Clinical History to Document

Transfusion and Pregnancy History (Most Important)

You must explicitly state on the form whether the patient has received a transfusion OR been pregnant within the previous 3 months 1, 2. This is critical because:

• If yes to either: the sample is only valid for 72 hours from collection to transfusion 1, 2
• New antibodies can develop rapidly following antigenic exposure, necessitating this shortened validity window 2
• Failure to document this can lead to delayed hemolytic transfusion reactions from newly formed antibodies 2

Specific Test Request Details

Document the following on the pathology form:

• Specify both IgM and IgG titre testing 3, 4, 5
• Indicate if this is for ABO-incompatible transplantation monitoring (stem cell or solid organ) 4, 5
• Note any previous ABO incompatibility reactions 3, 5

Additional Clinical Context to Include

For Transplant Patients

• Type of transplant planned or completed (hematopoietic vs. solid organ) 5
• Baseline titre if monitoring post-transplant 4
• Whether patient is on immunosuppression (affects titre interpretation) 4

For Hemolytic Disease Monitoring

• Gestational age if pregnant 5
• Previous affected pregnancies 5
• Partner's blood group if known 5

Sample Collection Documentation

Document that the sample was collected and labeled at the patient's bedside by appropriately trained personnel 1. This is paramount for patient safety.

Historical Sample Considerations

If a historical sample exists 1:

• Note the date of the historical sample 1
• Confirm electronic transmission with no manual intervention 1
• Document that patient identification matches between samples 1

Common Pitfalls to Avoid

Do not assume the laboratory will know about recent transfusions or pregnancies without explicit documentation 1, 2. The 72-hour validity rule is absolute for these patients, and failure to communicate this history can result in:

• Use of expired samples for crossmatching 2
• Missed newly developed antibodies 2
• Acute hemolytic transfusion reactions from ABO incompatibility 1, 5

Do not request "ABO typing" when you actually need "ABO titres" - these are different tests 4. ABO titres specifically measure antibody levels (IgM and IgG), which is essential for transplant monitoring and incompatibility assessment 3, 4, 5.

Method Specification (If Relevant)

For specialized situations, you may specify the preferred testing method 4:

• Tube haemagglutination (traditional method) 4
• Micro-column agglutination 4
• Erythrocyte-magnetized technology (EMT) (automated method that typically yields higher titres) 4

Note that EMT methods produce higher median titres than conventional methods, so serial monitoring should use the same methodology 4.