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Hold for em 6.30
the customer reported a false negative dat (direct anti-globulin test) result of an adult patient sample with an ih-card ahg anti-igg, -c3d.The customer tested on ih-1000 and manually.Additionally, the customer tested on the ih-card ahg anti-igg manually and on ih-1000 and received a positive result in each case.The customer provided the complaint sample ih-card ahg anti-igg, -c3d for investigational testing and also two patient samples.The customer returned two single cards.The investigation of our quality control laboratory is still ongoing.Also still ongoing is the investigation of the affected ih_1000 instrument.A review of the batch record documentation showed no irregularities which might have negatively affected the quality of the allegedly defective card lot.
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The customer reported false negative dat (direct anti-globulin test) results of a cord blood sample and an adult sample.The customer tested on the ih-1000 instrument and manually and received discrepant results.The customer sent us 1 tube each of the two samples in question, as well as ih-cards from two different lots and configurations.The customer provided trace files of the affected ih-1000 instrument for investigation.The investigation did not give any indication for a malfunction of the affected dievice.Cord blood (id #476091) reacted negatively with ih-card ahg anti-igg lot #9126030 on the ih-1000 and in manual gel-card testing, but positively in tube testing with monospecific ahg.Repeat testing twice on the ih-1000 also resulted in negative reactions.A loading with anti-a of the cord blood was known.Adult blood (#477162) reacted negatively with the ih-card ahg anti-igg, -c3d lot #9111050 both on the ih1000, in the manual gel-card test and with the polyspecific ahg in the tube method.However, positive reactions occurred when using the ih-card ahg anti-igg lot #9126030, also in the repeat test on the ih-1000 and in the manual gel method.In the tube test with monospecific ahg, the sample reacted negatively.However, negative reactions occurred when using the ih-card ahg anti-igg lot #9133030 in the manual gel method.The ih-cards (lot #9126030 and lot #9111050) returned by the customer as well as our quality control lab's retention samples of the three ahg lots used by the customer were visually checked and did not show any abnormalities.All acceptance criteria were met.Since the two patient samples sent for investigational testing were in poor condition due to hemolysis, they first had to be washed several times for testing.The test was then performed on the ih-1000.Two known weakly igg loaded red blood cells were included as controls.Furthermore, six donor sample (dat negative) were tested.Result: both samples reacted negatively with both the customer cards and the three qc samples.The two known dat positive red blood cells reacted weakly positive; the six donor samples reacted negatively.The two provided patient samples were tested using the tube method with monospecific ahg, polyspecific ahg as well as polyspecific ahg from ortho.Both samples reacted negatively with all three ahgs used.The two patient samples were also tested in the manual gel method.The adult blood sample reacted negatively.The cord blood sample showed very weak positive reactions, which were only visible with the help of the illuminated box.Therefore, a 2% red blood cell suspension was prepared.This resulted in a 1+ reaction (the 2% red blood cell negative control was correctly negative).The two patient samples were checked in the id-card ahg anti-igg and id-card ahg anti-igg, -c3d.The adult blood sample reacted negatively.The cord blood sample showed a 1+ positive reaction in the id-card ahg.The cord blood sample was then tested in the dc screening card i with the result that the red blood cells were loaded with igg.The three ahg lots were checked for potency in comparison to the id-card ahg with anti-d and anti-fya loaded red blood cells.All cards showed comparable results.But the id-card reacted half a titer step stronger compared to the three ih-card lots.Based on the investigation the complaint was classified as unjustified.The negative reaction of the adult sample in the ih-card ahg anti-igg, -c3d was correct.The correct functioning of the three ih-cards in question could be verified.We could not confirm the positive reactions of the customer's adult sample in the ih-card ahg anti-igg lot #9126030.The sample reacted negatively in all tests.The root cause of the false positive reaction at customer´s site remained unknown.A carry over could be excluded.A review of the batch record documentation showed no irregularities which might have negatively affected the quality of the allegedly defective lot.
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