A prospective study to assess the predictive value for hereditary spherocytosis using five laboratory tests (cryohemolysis test, eosin-5'-maleimide flow cytometry, osmotic fragility test, autohemolysis test, and SDS-PAGE) on 50 hereditary spherocytosis fa

CRISP R; SOLARI L; VOTA D; GARCÍA E; MIGUEZ G; CHAMORRO ME; SCHVARTZMAN G; ALFONSO G; GAMMELA D; CALDAROLA S; RICCHIERI C; VITTORI D; VENEGAS B; NESSE A; DONATO H

ANNALS OF HEMATOLOGY

SPRINGER

Año: 2011 vol. 96 p. 625 - 634

0939-5555

This prospective study was carried out to assessthe usefulness of five laboratory tests in the diagnosis ofhereditary spherocytosis (HS), based on the correlation oferythrocyte membrane protein defects with clinical andlaboratory features, and also to determine the membraneprotein deficiencies detected in Argentina. Of 116 patientsand their family members tested, 62 of them werediagnosed to have HS. The specificity of cryohemolysis(CH) test was 95.2%, and its cut-off value to distinguish HSfrom normal was 2.8%. For flow cytometry, cut-off pointsof 17% for mean channel fluorescence (MCF) decrease and14% coefficient of variation (CV) increase showed 95.9%and 92.2% specificity, respectively. Both tests showed thehighest percentages of positive results for diagnosis. EitherCH or flow cytometry was positive in 93.5% of patients. Ineight patients, flow cytometry was positive only throughCV increase. Protein defects were detected in 72.3% ofpatients; ankyrin and spectrin were the most frequentlyfound deficiencies. The CV of the fluorescence showedsignificantly higher increases in moderate and severeanemia than in mild anemia (p=0.003). Severity of anemiashowed no other correlation with tests results, type ofdeficient protein, inheritance pattern, or neonatal jaundice.CH and flow cytometry are easy methods with the highestdiagnostic accuracy. Simultaneous reading of mean channelfluorescence (MCF) decrease and CV increase improvediagnostic usefulness of flow cytometry. This test seems tobe a reliable predictor of severity. The type of detectedprotein deficiency has no predictive value for outcome.Predominant ankyrin and spectrin deficiencies agree withreports from other Latin American countries.