The siemens customer service engineer (cse) performed a complete performance inspection of the system.Several parts were replaced proactively.The wash manifold was cleaned, fluid lines checked, dark counts were good, dispense volumes were good.Background testing showed no indication of contamination.A precision run of n=10 for level 1 and 2 was performed with good precision.The customer was not able to provide information on the blood collection tube, how long it was allowed to clot, and whether it was centrifuged.Insufficient clot time and insufficient centrifugation can lead to particulate matter in a sample that could interfere with the advia centaur xpt afp assay.If samples are transferred to a secondary tube, they should be recentrifuged in the secondary tube before being tested.The cause for the discordant afp results is unknown.Possible sample handling.The instrument is performing within specifications.No further evaluation of the device is required.The ifu states in the warning section: "warning the concentration of afp in a given specimen, as determined by assays from different manufacturers, can vary due to differences in assay methods and reagent specificity.The results reported by the laboratory to the physician must include the identity of the afp assay used.Values obtained with different afp assay methods cannot be used interchangeably.Before changing assay methods, the laboratory must do the following: - for prenatal testing, the laboratory must establish a range of normal values for the new assay based on normal serum and amniotic fluid from pregnant women with a confirmed gestational age.- for cancer management, the laboratory must perform additional testing to confirm baseline values for patients being serially monitored.United states federal law restricts this device to sale and distribution by or on the order of a physician, or to a clinical laboratory; and use is restricted to, by, or on the order of a physician.Use afp results only as part of the overall clinical evaluation of a patient.Do not use afp results as the only criterion for diagnosis." the ifu states in the interpretation of results section: "results of this assay should always be interpreted in conjunction with patient's medical history, clinical presentation and other findings.".
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