title: [Flow cytometric test using eosin-5'-maleimide (EMA) labelling of red blood for diagnosis of hereditary spherocytosis].
abstract: OBJECTIVE
  To investigate the sensitivity and specificity of eosin-5'-maleimide (EMA)assay for the diagnosis of hereditary spherocytosis (HS), and to verify the stability of reagent and samples.
  
  
  METHODS
  EMA flow cytometry test, NaCl-osmotic fragility test and acidified glycerol lysis test were performed using peripheral blood samples from 80 patients with HS and 44 patients with other blood diseases, the sensitivity and specificity of the three methods were compared, and the feasibility of EMA binding test was estimated. The stability of EMA reagent and HS samples stored at different temperatures were tested.
  
  
  RESULTS
  Among the 124 tested samples, the sensitivity and specificity of EMA binding test was 0.925 and 0.954, that of NaCl-osmotic fragility test was 0.950 and 0.455, and that of acidified glycerol lysis test was 1.000 and 0.318, respectively. Although the sensitivity of NaCl-osmotic fragility test and acidified glycerol lysis test was a little higher than that of EMA binding test, the specificity of the former two methods was poor, they couldn't clearly distinguish whether spherocytosis is hereditary spherocytosis. The experiment results showed that EMA was sensitive to the temperature and should not be stored in a small aliquots at -80 ℃ over a period of 6 months. The stability of the HS sample was better, 6 days storage at 4 ℃ and 3 days storage at room temperature had no influence on the results.
  
  
  CONCLUSIONS
  EMA binding test by flow cytometry showed good sensitivity and specificity for HS diagnosis. EMA reagent should be stored at-80 ℃ and the HS samples should be tested within 6 days storage at 4 ℃ and 3 days at room temperature.
authors: Institute of Hematology and Blood Disease Hospital, CAMS & PUMC, Tianjin 300020, China.
authors: Jiying
authors: J
authors: Wang
authors: Institute of Hematology and Blood Disease Hospital, CAMS & PUMC, Tianjin 300020, China.
authors: Bin
authors: B
authors: Zheng
authors: Institute of Hematology and Blood Disease Hospital, CAMS & PUMC, Tianjin 300020, China.
authors: Yuping
authors: Y
authors: Zhao
authors: Institute of Hematology and Blood Disease Hospital, CAMS & PUMC, Tianjin 300020, China.
authors: Xuejing
authors: X
authors: Chen
authors: Institute of Hematology and Blood Disease Hospital, CAMS & PUMC, Tianjin 300020, China.
authors: Yan
authors: Y
authors: Liu
authors: Institute of Hematology and Blood Disease Hospital, CAMS & PUMC, Tianjin 300020, China.
authors: Lijin
authors: L
authors: Bo
authors: Institute of Hematology and Blood Disease Hospital, CAMS & PUMC, Tianjin 300020, China.
authors: Yizhou
authors: Y
authors: Zheng
authors: Institute of Hematology and Blood Disease Hospital, CAMS & PUMC, Tianjin 300020, China.
authors: Fengkui
authors: F
authors: Zhang
authors: Institute of Hematology and Blood Disease Hospital, CAMS & PUMC, Tianjin 300020, China.
authors: Kun
authors: K
authors: Ru
authors: Institute of Hematology and Blood Disease Hospital, CAMS & PUMC, Tianjin 300020, China.
authors: Huijun
authors: H
authors: Wang
mesh_terms: D017487:Ankyrins / Q000097:blood / Q000172:deficiency*; D004801:Eosine Yellowish-(YS) / Q000031:analogs & derivatives*; D005434:Flow Cytometry; D006403:Hematologic Tests; D006801:Humans; D012680:Sensitivity and Specificity; D013103:Spherocytosis, Hereditary / Q000097:blood / Q000175:diagnosis*
chemical_list: D017487:Ankyrins; C033531:eosin maleimide; D004801:Eosine Yellowish-(YS)