Alere Inc., has initiated a voluntary correction to inform U.S. users of the Alere INRatio and INRatio2 PT/INR Monitor system of certain medical conditions that should not be tested with the system (INRatio Monitor or INRatio2 Monitor and INRatio Test Strips). In certain cases an INRatio and INRatio2 PT/INR Monitor system may provide an INR result that is clinically significantly lower than a result obtained using a reference INR system (laboratory method). This issue can arise if the patient has certain medical conditions or can occur if the instructions in the labeling for performing the test are not followed.
The INRatio and INRatio2 PT/INR Monitor system should not be used on patients with any of the following conditions: anemia of any type with hematocrit less than 30%; any conditions associated with elevated fibrinogen levels including acute inflammatory conditions (examples may include acute viral or bacterial infections such as pneumonia or influenza); chronic inflammatory conditions (examples may include rheumatoid arthritis, Crohn’s disease, ulcerative colitis, infectious liver diseases such as hepatitis, or inflammatory kidney diseases such as diabetic nephropathy and glomerulonephritis); severe infection (e.g., sepsis); chronically elevated fibrinogen for any reason; hospitalized or advanced stage cancer or end stage renal disease patients requiring hemodialysis; and any bleeding or unusual bruising, clinically observed or reported by the patient. Patients with any of the conditions listed above should immediately be transitioned to a laboratory INR method for monitoring their INR and warfarin therapy.
Alere also recommends that patients be tested to verify that their hematocrit falls within the range of 30% to 55%. Patients with hematocrit outside this range should be immediately transitioned to a plasma-based laboratory INR monitoring method.
Alere is working on an improvement to the current INRatio and INRatio2 meter, which will serve to mitigate further the potential for these discrepant results. Alere has reported these device concerns to the U.S. Food and Drug Administration and is conducting a thorough investigation into these events.Read more on the FDA website