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Serological diagnosis of syphilis can be made by using the serological test for syphilis (STS) method for detecting a lipid antibody and Treponema pallidum (TP) method for detecting the anti-TP-specific antibody. In STS and TP methods, the basis using latex agglutination reaction has been used in many facilities. However, in latex agglutination, false-positive results due to non-specific reaction have sometimes been obtained in reactions of a routine laboratory test reagent detecting the anti-TP antibody used in our medical laboratory. We evaluated the fundamental performance of 4 reagents to measure anti-TP antibody concentration using latex agglutination: Reagents A, B, C and D produced by SEKISUI MEDICAL, FUJI REBIO, DENKA SEIKEN and SHINO TEST, respectively. We examined the correlations between Reagent A (routine laboratory test reagent) and Reagents B, C, and D in sera from 68 patients, and we performed additional investigation by using a neutralization test, immunochromatography, Western blotting, FTA-ABS (IgG), and STS method by an automatic analyzer for 13 decision-mismatched samples. The fundamental performance of each reagent was as good as that previously reported. Eight of the 13 decision-mismatched samples were false positives due to non-specific reaction of Reagent A. In latex agglutination non-specific reaction is inevitable. However, this study strongly suggests that using a neutralization test and immunochromatography that can be performed quickly is sufficient to verify whether positive reactions are true or false.

It has been reported that fibrinogen products, such as fibrinogen concentrates, cryoprecipitate (CRYO), and fresh frozen plasma, are beneficial for treating coagulopathy due to massive blood transfusion. For the appropriate use of these products, it is necessary to evaluate the status of coagulopathy and determine the trigger level of the fibrinogen concentration for the administration of fibrinogen products. In our institution, we established a treatment procedure for coagulopathy due to massive transfusion in 2011. This procedure includes determination of the trigger level for administration of CRYO (150 mg/dL), timing of sample collection for the evaluation of coagulation parameters (prothrombin time, activated partial thromboplastin time, and fibrinogen) and concentration status during the operation, and a method for rapid coagulation testing (turnaround time within 15 minutes) in critical bleeding. Since 2011, we have performed 56 rapid coagulation tests for patients suffering from critical bleeding. The average turnover time was 13 minutes. According to the rapid coagulation test results, CRYO was administered to 27 patients. These results are satisfactory for treating critical bleeding patients. We stress the need for the establishment of a rapid coagulation test system in the central hospital laboratory. (Review).

In 2007, "the Guidelines for Actions against Intraoperative Critical Hemorrhage" were established by the Japanese Society of Anaesthesiologists and the Japanese Society of Blood transfusion and Cell Therapy. The documentation of in-hospital procedures for critical hemorrhage, especially about how to select RBC units, has widely standardized hospital practice. Patients with intraoperative critical hemorrhage sometimes suffer from massive blood loss. In this situation, some patients develop coagulopathy. To treat them, we need to evaluate their coagulation status based on laboratory test results. So, we performed a nationwide questionnaire survey on the current status of hospital clinical laboratories evaluating critical hemorrhage. From the results of this survey, it was recommended that central hospital laboratories should try to reduce the turn-around time required to test for coagulation parameters as much as possible for appropriate substitution therapy. (Review).

We compared the results of two bacterial identification methods: 1) a traditional method based on phenotypic identification of the causative organism using gram-staining, culture and biochemical markers and 2) matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). A total of 111 isolates, including 107 strains of common bacteria species and 4 strains of 3 yeast species, were tested by the traditional method and MALDI-TOF MS method(VITEK MS and Micro flex LT). Data obtained using MALDI-TOF MS were classified as Level 1 and Level 2 according to the confidence level of identification results from the VITEK MS ver. 1.0 database (VITEK MS) and MALDI Biotyper ver. 2.0 database (Microflex LT). The proportions of measured samples identified as Level 1 were 98.2% with the VITEK MS database and 87.4% with the MALDI Biotyper database. The concordance rates of the traditional method were 93.7% with the VITEK MS database and 82.0% with the MALDI Biotyper database. Identification results of five strains were mismatched between the traditional method and MALDI-TOF MS. Their ribosomal RNA sequences were identical to the results obtained from MALDI-TOF MS. We concluded that the performance of VITEK MS is superior to that of the traditional method and Microflex LT.

The rapidity of coagulation testing is important for use as appropriate substitution therapy in patients with, or at risk of critical bleeding requiring massive transfusion. Whereas the ordinary method of coagulation testing is known to be slow, in a critically haemorrhaging patient, a rapid turnaround time of coagulation testing becomes indispensable. To find out if coagulation test results will be affected by a shortened centrifugation time, we measured PT (prothrombin time), APTT (activated partial thromboplastin time), FIB (fibrinogen) and PLT (platelet) in plasma, using different centrifugation times (10 min, 5 min, 3 min), and analyzed the measurements. We found that, whereas centrifugation time significantly affected the PLT count in plasma (10 min; 5.17 +/- 3.71 x 10(3)/microl, 5min; 28. +/- 26.9 x 10(3)/microl, 3min; 63.7 x 10(3)/microl), PT(10min; 14.6 +/- 5.76 sec, 5min; 14.7 +/- 5.84 sec, 3min; 14.9 +/- 6.40 sec), APTT (10min; 36.4 +/- 15.9 sec, 5min; 36.8 +/- 16.5 sec, 3min; 34.7 +/- 11.4 sec) and FIB(10min; 361 +/- 134 mg/dl, 5min; 356 +/- 132 mg/dl, 3min; 356 +/- 125 mg/dl) were not affected. These data suggest that shortening centrifugation time will have no significant effect on the value of PT, APTT and FIB, in an emergency situation.

Recent progress of fundamental and clinical studies on cystatin C was reviewed. Most of key studies are indebted to prof. Grubb A and his groups. International contributions from Japanese research work are included here. The protein is a basic low molecular weight protein of 13,300 with 120 amino acid residues and pI 9.3, functioning as a cysteine protease inhibitor. With an introduction of ERM-DA471, international reference material for serum cystatin C, global standardization for immunoassay systems has been much facilitated. No serious problems are present in the pre-analytical stage. Serum reference intervals are properly set in all Asian populations including Japanese with age and gender-related differences. The protein is a powerful serum intrinsic marker for glomerular filtration rate. Estimated glomerular filtration rate (eGFRcysC) in coupled with eGFRCr will definitely be a clinical routine for early detection and prevention of altered kidney function and cardiovascular events in general population. Genetic tests clinically indicated include hereditary cystatin C amyloid angiopathy (L68Q) and adult macular degeneration (A25T) although their frequency is extremely low.

The microvascular bleeding resulting from the dilutional coagulopathy can occur when patients with massive blood loss are treated by infusing a lot of crystalloids, colloids, and red blood cell concentrates. For the management of dilutional coagulopathy and the appropriate replacement therapy of with coagulation factors and platelets, we usually monitor the patient's course of with platelet count, conventional coagulation tests such as the prothrombin time, the activated partial prothrombin time, and the fibrinogen concentration. The central clinical laboratory has a responsibility for an accurate and quick report of these test results of patients with massive transfusion. Furthermore, use of point care testing is of clinical value to fulfill a clinical demand in case with dilutional coagulopathy.

Carotid ultrasonography is useful for patients in the early stage of atherosclerosis or with manifest vascular disease. We can assess the intima-media thickness (IMT), stenosis, and also elasticity of the carotid artery noninvasively. IMT is well-known as a strong predictor of future vascular events and a surrogate marker of atherosclerosis. We examined 353 consecutive subjects (coronary artery disease: n=92, cerebral vascular disease: n=62, peripheral arterial disease: n=104), regarding whether the accumulation of vascular diseases affects the IMT. The maximum IMT of the common carotid artery expanded with increasing numbers of vascular diseases (no vascular disease, 1.10 +/- 0.51; one vascular disease, 1.38 +/- 0.63; two vascular diseases, 1.69 +/- 0.65; three vascular diseases, 2.01 +/- 0.67 mm; p < 0.01, no vs. one vascular disease, one vs. two vascular diseases). The accumulation of vascular diseases, independent of the types of vascular lesion, accelerated carotid atherosclerosis. The stiffness parameter beta of the carotid artery was related to the brachial-to-ankle pulse wave velocity(baPWV) (n=38, r = 0.81, p < 0.0001). Stiffness parameter beta (10.95 +/- 2.8) and baPWV (1,549 +/- 179 cm/s) in the metabolic syndrome (MetS) group (n=18) was higher than in the preliminary MetS (n=12, 8.82 +/- 1.69, 1417 +/- 148 cm/s) and control (n=8, 7.90 +/- 1.78, 1357 +/- 171 cm/s) groups. The mean IMT of the common carotid artery was not different between the MetS and preliminary MetS groups. Morphological and functional changes in atherosclerosis can be evaluated employing carotid ultrasonography.