Reticulocyte analysis in iron deficiency anemia and hemolytic anemia.

Reticulocyte analysis was studied in 28 anemic patients, 15 with iron deficiency anemia (IDA), and 13 with hemolytic anemia including 9 glucose 6 phosphate dehydrogenase deficiency (G6PD def.), and 4 with G6PD def. combined with HbE trait or alpha thalassemia trait (alpha thal trait). The reticulocyte analysis among these patients showed the increased number of reticulocyte percentage with low degree of maturation in both IDA and G6PD def. patients. The significantly decreased reticulocyte hemoglobin content (CHr) was found in IDA (CHr = 21.74 +/- 4.61 pg in IDA vs 28.41 +/- 1.34 pg in normal; p-value = < 0.0001), whereas, increased CHr was found in G6PD def. patients. In addition, the G6PD def. patients also showed a significant increase in mean corpuscular reticulocyte volume (MCVr) when compared to normal (MCVr = 132.0 +/- 8.39 fl. in G6PD def. vs 110.39 +/- 5.09 in normal; p-value = < 0.0001). However, a significant decrease in MCVr was found in IDA patients (MCVr = 95.89 +/- 8.57 fl.; p-value = < 0.0001 vs normal). From this study, we can suggest that the reticulocyte hemoglobin content (CHr) and mean corpuscular reticulocyte volume (MCVr) are the important defects in patients with iron deficiency anemia.

Reticulocyte analysis in systemic lupus erythematosus and chronic renal failure using flow cytometry.

The number and maturation of circulating reticulocytes were measured in patients with systemic lupus erythematosus (SLE) and chronic renal failure (CRF) using an automated hematological analyzer (Technicon H*3 RTX) for their erythropoietic activities. Both SLE and CRF patients had increased reticulocyte numbers with a low degree of maturation. The SLE patients had no changes in mean reticulocyte corpuscular volume (MCVr) as compared to normal subjects (110.20 +/- 15.43 fl. in SLE and 110.39 +/- 5.09 fl. in normal), whereas CRF patients had significantly increased mean corpuscular reticulocyte volume (MCVr = 120.99 +/- 8.09 fl., p-value = 0.0019 as compared with normal). Three cases of SLE with nephrotic syndrome (NS) had high degree of MCVr (113.4, 125.0 and 133.1 fl., respectively). The renal involvement in SLE patients and CRF patients may associate with increased reticulocyte corpuscular volume.

Plan and process for hematology laboratory standard in Thailand.

In Thailand, there are around 2,000 clinical laboratories in private and government hospitals, By the end of year 2004, all of these laboratories are required to use the same or comparable standard nationwide. Many laboratories are in the process of starting ISO/IEC Guide 25 for the fulfillment of laboratory accreditation. To run the standard system of hematology laboratories in Thailand, we have considered three main aspects: standard in process, method selection and academic interpretation. Because of the wide spectrum of blood diseases in Thailand: thalassemia, iron deficiency anemia and G6PD deficiency hemolytic disease, the analysis and interpretation of laboratory results using different technology are of great importance. National plan has thus set up in two direction, one for standard process and another for academic approach.

Hematology laboratory standardization: a plan for harmonization in Asia.

Hematology laboratory is generally required in the hospital. At the macroscale, hematology laboratories have served a large number of population. In Asia, more than 3,000 million people are potentially to use the hematology laboratory service, particularly the complete blood count. Since 1970s, automated technology has been introduced to Asia and as years passed by, technology diversity is increasing. However, there are considerable number of hematology laboratories that have no automated machine. They are still relied on manual technology which is still variable in spectrophotometer for hemoglobin determination, centrifuge for hematocrit and diluting pipet for cell counting. In particular, blood smear preparation and interpretation are very difficult to control for standardization from person to person and laboratory to laboratory. Different methodology and a large population in the huge geographical area in Asia, the agreement of standard criteria is greatly important. This report has shown strategy and action plan to reach the goal of hematology laboratory standardization in Asia.

Field evaluation of who hemoglobin color scale in West Java.

The results obtained with a WHO hemoglobin (Hb) colour scale were evaluated in a field study in Chibubur district in Java island by comparison with hemoglobin values obtained by an automated blood cell analyzer K-800 (Sysmex. Kobe, Japan). When the color scale test was performed following the instructions for use. Hb values observed were usually higher than the values obtained by the analyzer. Thirty microl blood was loaded on the filter paper and an 60 sec waiting period was used. The sensitivity of results obtained with the color scale was 23.3% (14/60), and specificity was 96.6% (58/60). We propose an additional testing method based on our results.

Laboratory accreditation: quality in management and analysis and the input-output control.

An attempt to overcome the uncertainties and errors of all processes in clinical laboratory has been done in systematic ways. To reach the stage of laboratory accreditation, quality and standard criteria in the laboratory must be developed. Two aspects of quality are considered as management and analysis. Input-output control is proposed to handle the process from the beginning of laboratory design until post analytical phase or the control at the outcome. The model of ten Ms including model, material, machine, man, mind, money, method, mechanism, measurement and menace and one O or outcome, is elaborated to cover pre-analytical, analytical and post-analytical phases. Laboratory accreditation is then an integral part of hospital accreditation with total quality management.

Icsh activities and Asia.

The International Council for Standardization in Haematology (ICSH), an international organization promoting international agreement on hematological testing, is now restructuring to strengthen its activities. In Asia, a diversity of testing methods exists and the resulting testing levels make it difficult to compare test results internationally among Asian countries. Fortunately, the ICSH is considering regionalizing its organization to 5 sub-societies to increase its activity, and we have been able to establish a new society, ICSH-Asia, under the ICSH umbrella.

Malaria protection in hereditary ovalocytosis: relation to red cell deformability, red cell parameters and degree of ovalocytosis.

In the culture of red cells with Plasmodium falciparum, erythrocytes from both Thai patients and subjects (patient's parents) with hereditary ovalocytosis have a protective effect against malarial infection. High percentage of ovalocyte (75-100%) was found in patients whereas their parents had lower percentage (25-50%). Invasion index (II) and multiplication ratio (MR) of P. falciparum in these abnormal red cells from the patients were significantly decreased as compared to those in normal red cells (patients: II = 1.52 +/- 0.91, MR = 8.83 +/- 6.73; normal subjects: II = 4.45 +/- 1.51, MR = 25.23 +/- 6.25). This suggests that the red cells from these patients had significant degree of malaria protection. The significant protection was also shown in red cells from the parent group (II = 1.86 +/- 0.81, MR = 15.69 +/- 3.50). Although the parents had lower ovalocyte percentage, degree of protection against malaria parasite was as effective as those found in patients with high ovalocytic red cells. This has been confirmed by statistical analysis showing nonsignificant difference in II value between the two groups. In contrast, red cells of both groups had poor deformability (deformability index, DI) as compared to the normal group. No statistically different DI values were demonstrated between the two. This indicates that poorly deformable red cells, not their ovalocytic shape, make a significant contribution to limitation of malaria parasite invasion. The MR values in patients were less than those found in the parent group but statistical analysis showed no significant difference. Reduced MR values were found with increased numbers of microcytic, hyperchromic and hypochromic red cells in patients.

Red cell parameters in alpha-thalassemia with and without beta-thalassemia trait or hemoglobin E trait.

Eighty-five patients who attended at Ramathibodi Hospital during November 1994 to June 1996 were investigated for thalassemia genotype, hemoglobin (Hb) typing and blood cell parameters. All patients were screened primarily for complete blood count using the Technicon H*3 automated hematology analyzer and Hb typing using the automated HPLC. Their genotypes were evaluated by in vitro gene amplification using primers for detection of common alpha-thalassemic genes found in the Thai population. We found 45 cases out of 85 were alpha-thalassemia trait with A2A typing, 10 were normal, 7 were alpha-thalassemia trait complicated by beta-thalassemia trait or HbE trait, 18 were HbH disease or HbH with Hb Constant Spring (HbH/CS), and 5 were AE Bart's disease. The alpha-thalassemia 1 trait had heterogeneity in red cell population as shown by increased red cell distribution width (RDW), the increased percent microcytic red cell (%Micro) and decreased mean cell volume (MCV). Red cell parameters in alpha-thalassemia 2 trait and HbCS trait were not significantly different from normal. The cases with coinheritance of alpha-thalassemia trait with beta-thalassemia trait or with HbE trait showed variation in their red cell parameters: one case showed less abnormal red cell parameters than those of uncomplicated alpha-thalassemia but the other two cases showed unimproved values. The homozygous alpha-thalassemia 2 showed similar red cell parameters to the alpha-thalassemia 1 trait. In conclusion, we can screen the alpha-thalassemia 1 trait and homozygous alpha-thalassemia 2 by using the simple red cell parameters such as the MCV and RDW; however, they must be confirmed for alpha-thalassemic genes. Unfortunately, red cell parameters of alpha-thalassemia 2 trait or HbCS trait were not different from those of normal subjects.

Possible evidence of endothelial cell activation and disturbance in thalassemia: an in vitro study.

Activation of vascular endothelium is considered as an important facet of inflammation, thrombosis, and vasculitis. Activated endothelial cells express a number of immunologically relevant surface markers which are not detected in dormant condition. These surface markers on endothelial cell may involve in adhesion reaction and migration of blood cell components. We demonstrated increased level of the soluble adhesion molecules in circulating blood of both alpha- and beta-thalassemic patients. These adhesion molecules are theoretically known to be released from endothelial cells. The adhesion molecules included soluble Intercellular Adhesion Molecule-1 (sICAM-1), soluble E-Selectin (ELAM-1), soluble Vascular Cell Adhesion Molecule-1 (sVCAM-1), and von Willebrand Factor (vWF). The levels of these adhesion molecules were measured in serum from 32 thalassemic patients and 10 control healthy subjects. As compared to normal, increased sICAM-1 was found in beta-thal/HbE patients with non-splenectomy; BE-NS (p = 0.002), increased ELAM-1 in beta-thal/HbE patients with splenectomy; BE-S (p = 0.01) and HbH with Hb Constant Spring; HbH/CS (p = 0.001), and increased sVCAM-1 in BE-NS; (p = < 0.0001) and BE-S (p = 0.002). Significant increase in von Willebrand Factor (vWF), a marker for endothelial cell, was shown in BE-S (p = 0.04) as compared to normal. Adhesion molecules were also markedly demonstrated in the supernatant of in vitro culture of human vascular endothelial cell in the presence of 30% thalassemic serum, and these adhesion molecules were also detected on the surface of the cells by using the technic of laser scanning confocal microscope and direct immunofluorescence.

Detection of thalassemia genes using smeared blood film or leukocytes adhering to polysthylene fibers.

Presently genetic analyses for thalassemia types require relatively large amounts of heparinized blood (5 to 10 ml), and transport as well as degeneration of these sample is a problem in the developing world. We have developed a new method to simplify this procedure and obtain DNAs from small specimens. As experimental materials, thinly smeared blood on a glass slide or blood filtered with and adhered on polysthylene telephtalate (PST) fibers were used. These materials could be safely stored without interfering with DNA extraction for up to 3 months. The slide materials were digested with proteinase K, and DNA was extracted with Tris-EDTA-phenol:chloroform and precipitated with absolute ethanol. The PST specimens were washed with physiologic saline and treated in the same manner as described above. Products were easily amplified by PCR and digested with restriction endonucleases for beta thalassemia typing as well as for HLA-DQA1 gene typing. Results obtained by this method correlated well with previously reported incidences for thalassemia and HLA-DQA1 types in Thailand. This method can be used in the routine laboratory because it allows for stable and biosafe genetic analyses.

Thalassemic serum inhibits endothelial cell mitosis in vitro.

Human umbilical vein endothelial cells were cultured in vitro using Iscove's Modified Dulbecco's Medium (IMDM) supplemented with either pooled normal human serum, or pooled thalassemic serum, or autologous umbilical cord serum, or fetal bovine serum. The mitotic activity was determined under the inverted phase contrast microscope and the number of mitotic cells was counted. Our results showed that the mitotic cells decreased in endothelial cell culture with thalassemic serum as compared with normal human serum, autologous umbilical cord serum or fetal bovine serum. The percentage of mitotic cells decreased on day 3 in the presence of beta-thalassemia/HbE serum from both splenectomized and non-splenectomized patients as compared with normal or autologous umbilical cord serum. In the presence of alpha-thalassemic serum, a similar outcome was also observed. From this study we can conclude that the thalassemic sera might contain factors which affect the endothelial cell growth and proliferation by inhibiting mitosis in vitro.

Dengue viruses induce cell proliferation and morphological changes of endothelial cells.

Replication of dengue viruses (type 1, 2, 3 and 4) in vitro in endothelial cells from human umbilical cord vein was demonstrated by virus titers and immunofluorescent antibody studies. Both showed highest peak at Day 6 after inoculation and declined to origin at Day 14. Some of the cultured endothelial cells detached from the culture well. Most of these floating cells were rarely viable as shown by failure in trypan blue exclusion whereas the adhering cells are mostly viable. More frequent and higher intensity of immunofluorescent positive cells were found in the detached cells as compared to adhering cells. The virus titers in the supernatant and in the adhering cell population were comparable, although floating cells were maximally 26.2% of the total cultured endothelial cells. Many floating cells and occasional adhering cells had numerous blebs on their surface. Endothelial cell proliferation was markedly increased after virus inoculation as compared with the control. Increased number of mitotic cells was also observed in the dengue virus-endothelial cell culture. Comparing among the four types, dengue type 4 induced highest peaks of cell proliferation and cell mitosis at Day 10 after inoculation. Dengue type 2 had the highest virus titers both in adhering cells and in supernatant at Day 6 as compared with other types.

Morphological alterations and apoptosis of endothelial cells induced by thalassemic serum in vitro.

Vascular complications such as lung thromboembolism and leg ulcer have been observed in thalassemic patients. Recently, our group has reported impaired proliferation of endothelial cells (ECs) after exposure to alpha- and beta-thalassemic sera in a culture system. This study was undertaken to detect apoptotic phenomena of ECs in the presence of alpha- and beta-thalassemic serum. ECs from normal human umbilical cord vein were exposed to 30% thalassemic serum in vitro and morphological changes were observed by using phase contrast, fluorescence and scanning electron microscopy. Such treated ECs presented morphological characteristics of apoptosis as shown by the appearance of compact cytosol, membrane blebbing, margination of nuclear matrix, condensed nuclei, and fragmented bodies. The majority of apoptotic cells was in the floating population. Similar morphological changes were also observed by treating ECs with hydrogen peroxide in the concentration range of 0.1-10 mM.

An in vitro study on thalassemic erythroid precursors in liquid culture.

Thalassemia is an inherited hematological disorder which can generally be classified according to the affected globin imbalance (alpha- or beta-globin) into two main types, i.e. alpha-thalassemia and beta-thalassemia, respectively. There is a wide range of cellular abnormalities associated with thalassemic erythrocytes such as hypochromia, microcytosis, reduced cellular deformability and membrane oxidative damage. The red cell abnormalities lead to premature destruction with marrow erythroid hyperplasia and ineffective erythropoiesis. The abnormalities in thalassemic red blood cells have been found along the erythroid differentiation pathway other than the mature stage as previously shown in bone marrow erythroid precursors and in reticulocytes, the penultimate stage of erythroid differentiation. However, there is a lag in our understanding of the more primitive erythroid stages due to the difficult and hazardous marrow aspiration and heterogeneity of cells derived. We have utilized a novel method of Two-Phase Liquid Culture (TPLC) of beta-thalassemia/HbE erythroid precursors instead of conventional semisolid culture. This type of liquid culture can given higher cell yield with quite synchronous cell differentiation stages and easily be applied for other cellular analytical techniques. The peripheral blood mononuclear cells (PBMC) obtained from non-splenectomized and splenectomized beta-thalassemia/HbE patients were first cultured in medium supplemented with 5637 conditioned medium for a 6-day period (phase I) and then transferred to medium supplemented with recombinant human erythropoietin to allow the terminal differentiation of erythroid precursors (phase II). During the phase I or II, the cultured cells were periodically sampled to determine the cell number, cytocentrifuged on glass slides and stained with Wright stain for morphological assessment of their differentiation stages and analyzed flow cytometrically by staining with fluoresceinated anti-transferrin receptor (anti-CD71) and R-phycoerythrin-conjugated anti-glycophorin A. After assessment by flow cytometry, the remaining stained cells were cytocentrifuged on glass slides and photographed by a fluorescent microscope and a laser scanning confocal microscope. The results of morphological assessment, flow cytometric analysis and microscopic pictures will be presented.

Alterations and pathology of thalassemic red cells: comparison between alpha- and beta-thalassemia.

Two main types of thalassemia have been categorized according to defective production of the globin gene ie alpha-thalassemia and beta-thalassemia. We report different red cell abnormalities between these two types. The study included 139 thalassemic patients including 91 patients with hemoglobin (Hb) H disease (52 cases with the classical genotype and 39 cases with Hb Constant Spring) and 48 were beta-thalassemia/Hb E disease. The deformability index of thalassemic red cells measured by laser diffractometer was significantly lower than that of normal red cells. Increased susceptibility of the thalassemic red cells to monocyte phagocytosis was markedly noted. Few sialic acid molecules were scattered on red cell surface of thalassemic red cells. Reticulocytes with delayed maturation stage were also observed in thalassemia indicating enhanced release from the bone marrow. The alpha-thalassemic red cells had relatively better deformability, increased susceptibility to phagocytosis, reduced sialic acid content and greater degree irregular distribution of sialic acid on red cell surface as compared to beta-thalassemic red cells. The alpha-type with hemoglobin Constant Spring (Hb CS) had increased percentage of reticulocyte and young reticulocyte (high fluorescent intensity) as compared to beta-thalassemic red cells. The different abnormalities between alpha- and beta-thalassemic red cells may lead to different mechanism of red cell destruction and different severity of the disease.

Dengue virus and endothelial cell: a related phenomenon to thrombocytopenia and granulocytopenia in dengue hemorrhagic fever.

Adhesion to endothelial cells by blood cells was assessed by measuring the cell number of each blood cell component in the supernatant after exposing blood cells to dengue-infected endothelial cells for 0, 10, 20 and 30 minutes. White blood cells, neutrophils, lymphocytes, platelets, and large lymphocytes or large unstained cells (LUC) preferentially bound to dengue-infected endothelial cells as compared to the control endothelial cells. P values were 0.0096 for total leukocytes and platelets, 0.006 for lymphocytes, and 0.001 for neutrophils and LUC. Monocytes basophils and eosinophils had no interaction with dengue-infected endothelial cells. The increased binding of neutrophil and platelet to endothelial cell may explain neutropenia and thrombocytopenia in DHF patients.

Differentiation of platelets from red cell fragments using laser technology: comparison between splenectomized and nonsplenectomized thalassemic patients.

Platelets from 59 beta-thalassemia/hemoglobin E (beta-thal/HbE) patients (19 were splenectomized) and 97 normal individuals were studied using laser and computer analysis. Fragmented red cells of similar platelet volume were differentiated from platelets using laser inspection of the intracellular hemoglobin of the fragmented red cell. The patients had increased platelet count than normal cases at p < 0.0001 (nonsplenectomized, mean +/- SE = 32.4 +/- 21.9; splenectomized, 617.5 +/- 64.2; normal, 264.7 +/- 6.4 x 10(3) cells/dl). Splenectomized patients had greater platelet counts than nonsplenectomized cases (p < 0.0001). Numbers of small red cells, probably red cell fragments, markedly increased in nonsplenectomized patients. Increased heterogeneity in platelet size was demonstrated in the patients of both groups. The nonsplenectomized patients had significantly higher mean platelet volume than normal (p < 0.02) and splenectomized cases (p < 0.01). Increased platelet number and heterogeneity in platelet population may involve in pulmonary thrombosis in splenectomized patients.

Size distribution curves of blood cells in thalassemias and hemoglobin H diseases.

Thalassemias and hemoglobinopathies in Thailand have been examined with a blood cell counter based on electroimpedance principle and obtained size distribution curves of red cells and platelets. Among various disorders, beta-thalassemia/hemoglobin E and homozygous hemoglobin Constant Spring showed severe anemia. Their red cell size distribution curve shifted to the left and overlapped with the platelet size distribution curve. Red cell distribution width expressed by coefficient of variation and the degree of the overlapping were stronger in beta-thalassemia/HbE than HbH. Heterozygous beta-thalassemia showed a narrow red cell distribution curve width with small standard deviation and low England's value. Although the overlapping of size distribution curves cause inaccurate red cell count and platelet count, careful observation of the size distribution curves was proved to have high diagnostic value.

Hypoxemia in thalassemia.

Data are reviewed describing hypoxemia, a newly identified feature in thalassemia. Evidence indicates platelet aggregation in the pulmonary circulation as being a key factor leading to hypoxemia and cor-pulmonale with right heart failure.