Automated reticulocyte parameters for hereditary spherocytosis screening

Abstract

The laboratory diagnosis of hereditary spherocytosis (HS) is based on several screening and confirmatory tests; our algorithm includes clinical features, red blood cell morphology analysis and cryohaemolysis test, and, in case of positive screening, sodium dodecyl sulphate polyacrylamide gel electrophoresis as a diagnostic test. Using the UniCel DxH800 (Beckman Coulter) haematology analyser, we investigated automated reticulocyte parameters as HS screening tool, i.e. mean reticulocyte volume (MRV), immature reticulocyte fraction (IRF) and mean sphered cell volume (MSCV). A total of 410 samples were screened. Gel electrophoresis was applied to 159 samples that were positive for the screening tests. A total of 48 patients were diagnosed as HS, and seven were diagnosed as acquired autoimmune haemolytic anaemia (AIHA). Some other 31 anaemic conditions were also studied. From the receiver operating characteristic (ROC) curve analysis, both delta (mean cell volume (MCV)-MSCV) and MRV presented an area under the curve (AUC) of 0.98. At the diagnostic cut-off of 100 % sensitivity, MRV showed the best specificity of 88 % and a positive likelihood ratio of 8.7. The parameters IRF, MRV and MSCV discriminated HS not only from controls and other tested pathologies but also from AIHA contrary to the cryohaemolysis test. In conclusion, automated reticulocyte parameters might be helpful for haemolytic anaemia diagnostic orientation even for general laboratories. In combination with cryohaemolysis, they ensure an effective and time-saving screening for HS for more specialised laboratories.

Blood cell parameters for screening and diagnosis of hereditary spherocytosis

“…Hemolytic anemia is a hyperproliferative anemia, characterized by increased peripheral blood reticulocytes and the appearance of various numbers of nucleated red blood cells. HS is characterized by a high Ret value with no increase in IRF, as reported by Lazarova et al However, this characteristic has a lower diagnostic sensitivity and specificity than MSCV‐MCV < 0, MRV, or MCHC.…”

“…Da Costa et al compared the membrane surface area of reticulocytes and mature erythrocytes and found that membrane vesiculation and membrane loss occurred at the reticulocyte stage in patients with HS, resulting in greatly reduced membrane surface area and MRV. Lazarova et al . examined blood cell parameters including MRV, MSCV, and IRF in 48 patients with HS, seven with AIHA, and 31 with other types of anemia and provided the first evidence for MRV as a valuable screening parameter.…”

“…Some previous studies have investigated the application of multiple blood cell parameters for HS screening, but have used different equipments and blood cell parameters. Lazarova et al examined the automated reticulocyte parameters MRV, IRF, and MSCV using a UniCel DxH 800 hematology analyzer (Beckman Coulter, Miami, FL, USA), while Mullier et al investigated the value of blood cell parameters MCV, MCHC, Ret, IRF, hypochromic erythrocytes, and microcytic erythrocytes using XE‐2100 and XE‐5000 automated hematology analyzers (Sysmex, Kobe, Japan). They were also the first to consider the three most common types of hemolytic anemia in China (including 56 cases of G6PD deficiency, 109 cases of THAL, and 52 cases of AIHA) as a disease control group and came to a valuable conclusion regarding HS screening and differential diagnosis.…”

Mean reticulocyte volume: a specific parameter to screen for hereditary spherocytosis

“…Lazarova et al . investigated MRV, MSCV, and immature reticulocyte fraction in 48 cases of HS, seven cases of AIHA, and 31 cases of other types of anemia; they reported that MRV could be used to screen HS. When the MRV was <96.7 fL, the sensitivity and specificity for diagnosing HS were 100% and 88%, respectively .…”

Identification and Verification of Hereditary Spherocytosis by Means of Laboratory Diagnosis

“…Для случаев НС с яркой клинической картиной соотношение RET/IRF составля-ет > 19. Выявлены статистически значимые различия в значениях показателя RET/IRF между группами паци-ентов с НС, гемолитическими анемиями, микроцити-ческими анемиями, пациентами без гематологических нарушений [16]. В нашем исследовании для всех случаев наследственного сфероцитоза показатель RET/IRF при-нимал значения более 19,5.…”