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This complaint was registered internally by siemens to document a false-negative advia centaur ahcv observation reported in an academic publication (adv lab med 2021; 2(2): 297-300).In the indicated case report, a false-negative (nonreactive) ahcv determination is described, and it is suggested that precipitation of cryoglobulins interfered with the measurement.The reagent lot used was not specified.The affected patient ((b)(6) woman) presented with renal failure and pulmonary edema.Following examination and extensive laboratory testing (including nonreactive advia centaur ahcv result), acute renal failure secondary to essential cryoglobulinemia was diagnosed.Cryoglobulinemia is commonly associated with hcv infection, but the infection was not detected in initial testing (and the likely cause of the cryoglobulinemia was not known).Viral-load testing, performed as part of the required dialysis protocol, revealed hcv infection.Following this determination, testing using the advia centaur ahcv assay was repeated using a sample which had been pre-warmed to 37 degrees (to reverse cryoprecipitation of proteins).This measurement produced a reactive result.The patient was not sufficiently stable for successful treatment, and ultimately died.It is noted that the patient exhibited no associated symptoms and no abnormal liver function parameters.The publication states the conclusion that "the patient presented a fatal outcome due to an hcv-secondary multisystemic vasculitis that could not be treated with a more aggressive therapy".Lack of treatment for the chronic hcv infection was not considered the cause of the death.The product's instructions for use (ifu) states the following in the limitations section: "a negative test result does not exclude the possibility of exposure to or infection with hcv.Hcv antibodies may be undetectable in some stages of the infection and in some clinical conditions." it should be noted that occasional false-negative results are expected, even in high-sensitivity applications such as the advia centaur ahcv assay.According to the assay's ifu, the resolved sensitivity of the advia centaur hcv assay was 100% (449/449) with a 95% confidence interval (ci) of 99.18 to 100%.The singular observation reported here does not indicate that the assay is not performing as intended.No product performance issue has been identified; no further investigation is planned.
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This mdr if being filed based on a review of the following publication: advances in laboratory medicine 2021; 2(2): 297-300: "false-seronegative hcv infection motivated by interference with cryoglobulins" authors: gemma recio comí, carmen molina clavero, sandra calabuig ballester, clara benavent bofill, ester picó-plana, carla martín grau, cristina gutiérrez fornés, ma teresa sans mateu this case report describes a false-negative hcv determination observed when using the advia centaur xpt hcv (ahcv) assay.The case involves an (b)(6) woman who was presented to the nephrology department with acute renal failure and pulmonary edema that required urgent haemodialysis.The patient exhibited drowsiness and disorientation, but acute pathology or infectious disease were excluded by a cranial computed tomography (ct) and a lumbar puncture.The patient showed meltzer's triad, composed of purpuric lesions, arthralgias and weakness.Initial laboratory tests confirmed kidney injury.Proteinuria was noted, and haematuria with dysmorphic erythrocytes was visualized in urinary sediment.Testing revealed normochromic and normocytic anaemia, and increased leukocyte count with neutrophilia.No abnormal coagulation values were found.Blood and urine cultures were negative.Chest x-ray and abdominal ct were both normal.Renal echography determined no morphological alterations.Kidney biopsy could not be performed due to the patient's poor general condition.Immunological testing showed decreased serum levels of c3 and c4 and elevated rheumatoid factor.Neither antinuclear antibodies nor antineutrophil cytoplasmic antibodies were found.Kappa/lambda-free light chain ratio and igm quantification were increased.A discrete band in gamma globulin fraction, composed of igm kappa, was detected in serum protein electrophoresis and immunofixation.However, marrow bone aspirate excluded blood malignancy.Viral serology tests were performed, and all were found to be negative, including hcv (measured using the siemens advia centaur xpt hcv (ahcv) assay).Further laboratory results revealed a type ii cryoglobulinemia composed of polyclonal igg and monoclonal igm kappa (cryocrit of 14%).Skin biopsy of petechiae was consistent with medium vessel vasculitis.In the absence of known causes for the observed cryoglobulin production, acute renal failure secondary to essential cryoglobulinemia was diagnosed.As established in dialysis protocol, hcv viral load was measured, producing an unexpected viral-positive result of 3,210,000 iu/ml.The patient had no hcv-associated symptoms, and no liver function biomarkers suggestive of hepatitis.Cross-contamination of samples and window period (timing of sampling) were eliminated as potential causes.Following these observations, the effect of in vitro cryoglobulins was suspected of having produced a false-seronegative hcv measurement.The advia centaur xpt hcv (ahcv) test was repeated on serum which had been kept at 37 °c for 60 minutes, to allow dissolution of putative cryoprecipitates.This test produced a reactive result of 2.68 index, indicating positive hcv infection.The patient was ultimately diagnosed with acute renal failure secondary to hcv-induced cryoglobulinemia.Other measures like immunoglobulin levels, c3 and c4 levels, rheumatoid factor, serum protein electrophoresis and immunofixation were also repeated using pre-heated serum in order to avoid spurious results due to cryoglobulin interference.Antiviral therapy could not be applied as the patient demonstrated a sudden inability to swallow.Indicated treatment of autoimmune features using corticosteroids, rituximab and/or plasmaphaeresis could not be applied as the patient was medically unstable, and not a candidate for aggressive medical care.In consideration of the severity of the disease and the patient's advanced age, the patient was not treated with rituximab or plasma exchange.The treatment was corticosteroid therapy for the extrahepatic manifestations, in addition to haemodialysis and furosemide for the renal failure.The patient showed deterioration with severe rectal bleeding due to multiple vascular lesions and apnoea episodes.Palliative care was applied, and the patient expired.The article states: "the lack of treatment for the chronic hcv infection was not considered the cause of the death.The patient had no symptoms and no abnormal liver function parameters (normal coagulation, normal transaminases, normal size and morphology liver, homogeneous, without focal lesions observed by ct).The patient presented a fatal outcome due to an hcv-secondary multisystemic vasculitis that could not be treated with a more aggressive therapy." the customer did not raise a complaint with siemens.Statements and actions attributed to the physician(s) and customer are derived from information provided in the article and have not been verified.
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