N Latex CDT Kit

Siemens Healthcare Diagnostics has observed a negative bias for the carbohydrate-deficient transferrin (CDT) measurement when using the affected N Latex CDT lots in comparison to the HPLC method. CDT results in absolute concentrations may be influenced by patients transferrin levels and, therefore, results are reported as ratio of CDT to total transferrin, called %CDT. As the transferrin determination with N Antiserum to Human Transferrin is not affected, the observed effect leads to calculated %CDT values that show a negative bias of approximately 15% compared to the HPLC method. This could result in a shift of weak positive patient samples into the reference range of 1.19 2.47 %CDT which was derived from a study population of healthy adults. There are no control or calibrator materials that would catch this bias.

On May 31, 2018 Siemens Healthcare Diagnostics issued Urgent Medical Device Correction notices (UMDC) PP18-002.A.US to the 4 affected customers in the U.S. Actions to be Taken by the Customer are as follows: Siemens Healthcare Diagnostics has assigned optimized values to the affected lots of standards and controls included in the kit lots. Those lots of standards and controls can be used with the revised assigned values and acceptance ranges. As per Urgent Medical Device Correction (UMDC) PP18-001.A.US, customers were instructed to: - Recalibrate your CDT method with N CDT Standard lots listed in the UMDC letter, using the revised assigned values provided in the UMDC letter. - Use the revised assigned values and respective ranges of the N CDT Controls provided in the UMDC letter. - For BN ProSpec and Atellica NEPH 630 customers, a new Lot Data CD as well as new Secure Download Files are expected to be available in June 2018, including the revised CDT target values for N CDT Standard, N CDT Control 1 and N CDT Control 2. - Please make sure that the values you manually entered according to this information are not overwritten by using an older Lota Data CD/Secure Download File afterwards. Customers are requested to complete and return the Effectiveness Check questionnaire attached to the Urgent Medical Device Correction letter and the Urgent Field Corrective Action letter within 30 days.