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In daily laboratory services, there are various factors associated with errors, such as those related to the principles of measurement, blood sampling procedure, or pathological condition. If medical technologists do not understand these factors, or adopt appropriate measures, they may face pitfalls. This paper outlines blood tests to develop basic knowledge of this area, and present examples of possible daily pitfalls and coun- termeasures against them. Regarding the blood count, it explains the mechanisms of automatic blood count devices and methods to manage erythrocyte aggregation, giant platelets, schizocytes, and platelet aggregation. Focusing on blood smears, it also examines the influences of excessive EDTA on blood cells, while discussing the mechanisms of automatic blood coagulation analyzers, as well as the influences of chyle and hematocrit levels on coagulation tests. Furthermore, in relation to the erythrocyte sedimentation rate, it confirms the principles of the international standard Westergren method and capillary photometry, and the influences of hematocrit levels. In order to avoid unexpected pitfalls, it may be important for medical technologists engaged in blood tests to implement their daily duties while fully understanding the necessity of: carefully observing individual spec- imens; clarifying related items (such as the patient's age, sex, and disease); and accurately recognizing the characteristics of individual test methods and reagents used within the facility, in addition to the principles of their measurement. [Review].

We introduce our efforts to utilize education, training, competence assessment, and quality control of personnel engaged in urinary sediment and blood cell morphology examinations in our laboratory. There are no standard samples for these morphological examinations, and standardization has not been completed for all types of blood cells or urinary sediment components. We had been carrying out simultaneous microscopic examination involving trainee staff and senior laboratory technologists as a means of education and evaluation, but acceptance criteria were unclear. Moreover, we had continued our operation without assessment of the level of achievement of routine works or the competence of individual staff members. Taking the opportunity of receiving ISO 15189 certification, we have been able to establish clear standards for evaluating personnel education and training in morphological examinations. We will continuously make efforts to maintain and manage this system.

A 64-year-old man was referred to our hospital because of mild anemia, erythroblasts in peripheral blood, and hyperferritinemia. In our hospital, no evidence of cytopenia was found. The peripheral blood smear showed pseudo-Pelger-Huët anomaly and giant platelets. The serum ferritin level was extremely high (1,405 ng/ml). A bone marrow examination was performed for further evaluation and revealed trilineage dysplasia. Since the patient did not fulfill the diagnostic criteria for cytopenias associated with myelodysplastic syndromes, he was diagnosed as having idiopathic dysplasia of undetermined/uncertain significance (IDUS). The SF3B1 mutation was identified in this patient, suggesting that he might be at a stage prior to myelodysplastic syndrome. Some IDUS patients reportedly progress to myeloid neoplasms, making careful observation essential. If morphological dysplasia in peripheral blood and hyperferritinemia are present, these findings suggest bone marrow failure syndromes. In such cases, further evaluation including a bone marrow examination may be required.

Liver fibrosis, most commonly caused by hepatitis virus (such as HBV and HCV) infections, excessive alcohol consumption, and obesity-induced steatosis, is characterized by the excessive accumulation of extracellular matrix proteins (including collagen) and an increase in connective-tissue (liver fibrogenesis) in the human liver. Today, while the reference standard for detecting and assessing liver fibrosis is needle biopsy of the liver, this invasive procedure can cause physical and emotional distress for patients. On the other hand, medical imaging systems and various blood markers have been developed and become available for routine laboratory practices. These non-invasive procedures, as well as pathological biopsy, have significantly contributed to assessing liver fibrosis. The Enhanced Liver Fibrosis (ELF) test is a simple blood test to create an ELF score by combining three markers: hyaluronic acid (HA), amino-terminal propeptide of type III procollagen (PIIINP), and tissue inhibitor of metalloproteinase 1 (TIMP-1). The ELF test is one of the promising techniques for diagnosing patients with liver fibrosis.

Since the direct method of LDL measurement is easy and convenient, many health evaluation and promotion facilities adopted it without sufficient discussion after specific health checkups started in Japan. For the purpose of reliable, specific health checkup data, we must review the methods and standardization of LDL measurement. I hope that medical societies, the Ministry of Health, Labour and Welfare, and reagent manufacturers will collaborate.

We are making efforts to reduce the number of venipuncture tubes for blood-based testing. On the reconstruction of hematology system in 2011, we planned the system to include hemoglobin A1c (HbA1c) assay and to replace the assay instrument for erythrocyte sedimentation rate (ESR) to use EDTA-2K based whole blood. Accordingly, the revised system required a single test tube for hematological testing, resulting in reduction of blood volume collected. It was estimated that the whole blood collected from outpatients in a year decreased from 143 L to 109 L. Also, the times required to complete venipuncture after outpatient accession were significantly shortened to 10(0.71 +/- 0.27) (2.75-9.55) min, and nearly 50% of outpatients experienced < 2 min of waiting. As the times required for venipuncture were shortened, the turnaround times (TATs) from outpatient accession to finally reporting the test results to physicians were also shortened in the blood-based laboratories. The TATs after outpatient accession to reporting the test results in biochemistry and serology ranged 59 to 80 min (90%-tile), indicating 8 to 16 min less when compared with those before system reconstruction. In conclusion, the decrease in number of venipuncture tubes in hematological testing enables us to reduce the blood volume collected, and to shorten (1) times required for venipuncture procedure, (2) waiting times, and (3) TATs for blood-based testing. However, as demonstrated in HbA1c, i.e., a 50%-tile of TAT for HbA1c delayed for 5 min, the configuration of assay system can greatly influence the TATs of individual test parameters.

Pre-operative autologous blood donation (PABD) provides safe blood for patients at the expense of the risk of iron deficiency anemia that may compromise the patients. The reticulocyte hemoglobin equivalent (RET-He) is an indirect measure of the functional iron available for the erythropoiesis over the previous 2-3 days. The aim of this study was to evaluate the clinical usefulness of RET-He quickly measured by the automated hematology analyzer Sysmex XE-2100 in patients undergoing PABD at our hospital. Receiver-operating characteristic curve analysis revealed that RET-He was reliable in the diagnosis of iron deficiency anemia. Two of 14 patients in the absence of post-PABD iron replacement developed marked anemia with low RET-He levels after PABD, suggesting that this anemia was due to iron deficiency. Of 26 patients receiving post-PABD iron replacement, 8 who had already showed low RET-He levels at PABD developed statistically significant reduction in hemoglobin levels after PABD despite adequate iron replacement, indicating that the 8 patients had iron deficiency prior to PABD. These findings suggest that automated measurement of RET-He may contribute to improve the safety of PABD.

For almost 100 years has the tuberculin skin test (TST) been used for the support the diagnosis of active and latent TB infection. The TST test has, however, a number of limitations most notable low specificity in BCG vaccinated individuals due to cross-reactive components in PPD and the M. bovis BCG vaccine strain and an intensive search for new and more specific diagnostic antigens has therefore be ongoing. In this review we describe the discovery process leading to the identification of the M. tuberculosis specific antigens ESAT6 and CFP10; two low molecular weight proteins which are highly sensitive and specific for detection of a M. tuberculosis infection.

We evaluated the delta check method for hematologic laboratories to detect specimen mix-up. We selected 271 patients with hematologic disorders and two types of investigation were conducted. The first investigation comprised statistical analysis, while the second involved evaluation of the procedure. From parameters of white blood cell, red blood cell, hemoglobin, hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin(MCH), mean corpuscular hemoglobin concentration (MCHC), and platelets, MCV was considered to represent the best single marker to detect artificial mix-up. About 98% of MCV delta values from one patient were within 3 fl. Conversely, 40% of MCV delta values in artificial mixups exceed 10 fl. No correlations between time interval and MCV delta values were detected. However, some cases were observed in which MCV delta values changed markedly over a short period of time even though the samples originated from one patient. In conclusion, we recommend investigation for specimen mix-up in cases where MCV delta values exceed 4 fl.

We have identified causative factors contributing to marked mean corpuscular volume(MCV) change. We selected 38 patients who demonstrated changes in MCV of > or = 10 fl within less than 30 days. Of the 38 patients, 27 had received blood transfusions and 6 had undergone allogeneic bone marrow transplantation within the previous 2 months. No definitive cause was detected in 5 patients. In conclusion, blood transfusion and bone marrow transplantation can result in substantial MCV change in a short time and can represent confounding factors for the MCV delta check method.

We calibrated the erythron transferrin uptake (ETU) and efficiency ratio (R-Ef) in erythropoiesis on the basis of ferroerythrokinetic data in 90 patients with iron deficiency anemia (IDA) and 64 patients with noncirrhotic and cirrhotic portal hypertension with splenomegaly (PH). Then we analyzed the data to elucidate how iron deficiency (ID) status effects variation of these values. ETU was significantly higher and R-Ef was lower in IDA subgroup before treatment (n = 71) than those with any recent treatment (n = 19), and in PH with anemia of ID type (PH-ID n = 39) than those without ID state (n = 34). A remarkable inverse correlation was obtained between ETU and R-Ef in both IDA and PH-ID and iron replacement therapy effected synchronous improvement of these values. We deduced the quantitative parameter of ID status (ID-x) on blood chemistry data in IDA by multiple regression of ETU and of R-Ef respectively. These calibration formulae were extrapolated to the data in PH-ID. Thus we delineate the factor which represents ID status in common to these two diseases to increase ETU and decrease R-Ef, although the contribution of ID-x was greater in IDA than PH-ID. Additional factors to enhance or modify these values were shortened survival of erythrocytes, splenomegaly and hepatic dysfunction.