A message from Dr Jo Scott-Jones, Pinnacle MHN medical director.
You may be aware of a concern raised about the accuracy of point of care testing for the International Normalised Ratio (INR). We have explored this with Dr Alan Neal from Pathlab and he has been extremely helpful, including obtaining a review of the issues and advice from haematologist Dr Paul Harper.
The issue only affects certain "chip lot codes" of test strips and only if readings are greater than 4.5.
The advice from Dr Harper is well articulated in the following patient scenarios.
This situation is continuing to be monitored and we will update you with any changes to this recommendation. We understand Canterbury Laboratories have taken another approach and have given clinicians in Canterbury advice to "double check" all point of care INR results >3.0. Pinnacle MHN, Medsafe, and Pathlab are happy with the above advice which reflects the issues raised by the manufacturer.For further information, this letter from Dr Paul Harper summarises the current situation, any risks and appropriate management as well as an updated recall document from Roche Diagnostics which includes clarifications around comparison measurements. For more information contact Dr Jo Scott-Jones, Pinnacle MHN medical director.