Challenges in antibody titration for ABO-incompatible renal transplantation

Area of Science:

• Immunology
• Transplantation Science
• Clinical Pathology

Background:

• Accurate monitoring of anti-A and anti-B antibody titres is critical for managing patients undergoing ABO-incompatible renal transplants.
• Currently, Australia lacks a standardized protocol or external quality assurance (EQA) program for this essential testing.
• This deficiency impacts consistent clinical interpretation and patient outcomes.

Purpose of the Study:

• To investigate the diversity of techniques, test platforms, and reagents used for ABO titration in Australian laboratories.
• To lay the groundwork for the development of a much-needed EQA program for ABO titration.
• To address the current lack of standardization in pre- and post-transplant antibody titre testing.

Main Methods:

• An online survey was distributed to participants of the Royal College of Pathologists of Australasia Quality Assurance Program (RCPAQAP).
• Twenty-four interested laboratories received group O plasma, A1, A2, and B cells to perform ABO titration using their established methods.
• Data on techniques, platforms, and reagents were collected to assess variability.

Main Results:

• A wide range of titre results were reported by participating laboratories.
• Reported anti-A titres varied from 8 to 1024 (using A1 cells) and 2 to 128 (using A2 cells).
• Anti-B titres ranged from neat to 32 (using B cells), indicating significant inter-laboratory variability.

Conclusions:

• Substantial variation exists in ABO titration results across different technologies and between laboratories.
• These findings underscore the urgent need for a standardized ABO titration external quality assurance (EQA) program in Australia.
• Implementing a standard technique and participating in an EQA program will reduce result variation, improve inter-center consistency, and enhance clinical decision-making for better patient outcomes.