title: Delayed Measurement of Eosin-5'-Maleimide Binding May Affect the Test Results of Highly Hemolyzed Samples In Vivo and In Vitro-A Case Study.
abstract: Diagnosis of hereditary spherocytosis (HS) is based on clinical evaluation and eosin-5'-maleimide (EMA) test. A decrease in EMA fluorescence compared with healthy individuals is typical for HS and serves as a basis for HS diagnosis. Sensitivity and specificity of the test is high and false-positive results rarely occur. Studies have shown that anticoagulated blood sample when stored at 4°C for 7 days do not affect the test results. This case study is about an autoimmune hemolytic anemia patient who showed a primary positive result for EMA test (decrease in EMA fluorescence-47% compared with 100% for samples of healthy individual), when the test was performed in the sample stored for 48 hours after venipuncture and before staining. An irrelevant decrease (92.5% compared with 100% for samples of healthy individual) was found when freshly collected sample was analyzed. On the basis of the results obtained, it is recommended that EMA staining should be performed on the same day of blood collection for patients with significant hemolysis.
authors.affiliation: Departments of *Laboratory Diagnostics and Clinical Immunology of Developmental Age †Paediatrics, Haematology and Oncology, Medical University of Warsaw, Poland.
authors.forename: Olga
authors.initials: O
authors.lastname: Ciepiela
authors.forename: Anna
authors.initials: A
authors.lastname: Adamowicz-Salach
authors.forename: Izabela
authors.initials: I
authors.lastname: Zdziechowicz
authors.forename: Iwona
authors.initials: I
authors.lastname: Kotuła
mesh_terms: D000744:Anemia, Hemolytic, Autoimmune / Q000150:complications*; D001800:Blood Specimen Collection / Q000379:methods; D002648:Child; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D004801:Eosine Yellowish-(YS) / Q000031:analogs & derivatives* / Q000032:analysis; D005260:Female; D006461:Hemolysis; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000175:diagnosis*; D013103:Spherocytosis, Hereditary / Q000175:diagnosis*; D013997:Time Factors
chemical_list: C033531:eosin maleimide; D004801:Eosine Yellowish-(YS)