Chronic kidney disease (CKD) has been shown to be a risk factor for cardiovascular disease. The vascular functional atherosclerotic change evaluated using the carotid stiffness parameter beta and cardio-ankle vascular index (CAVI) and the morphological change evaluated using carotid intima-media thickness (IMT) are widely examined in a clinical setting. The aim of the present study was to determine the correlation among these three atherosclerotic indices and the difference in the relationship between renal function and each index. Patients with simultaneous evaluation of IMT and stiffness parameter beta by carotid ultrasound sonography and CAVI were included in this study. A significant positive correlation was found between CAVI and mean IMT or stiffness parameter beta, but the correlation between mean IMT and stiffness parameter beta was not significant. CAVI and mean IMT, but not stiffness parameter beta, were significantly different among the 3 eGFR-based groups (G-1, eGFR ≧ 90; G-2, 60 ≦ eGFR < 90; G-3, eGFR < 60 ml/min/1.73 m²). However, CAVI, but not mean IMT, was significantly different between G-2 and G-3, although both indices were significantly different between G-1 and G-2. These results indicate that CAVI, but not mean IMT nor stiffness parameter beta, may be a suitable marker for CKD staging.

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The CLSI currently recommends sample preservation at ambient temperature for measuring PT, because cold-induced activation of blood coagulation factor Ⅶ due to low-temperature sample preservation may influence PT measurement. In this study, we investigated the effects of different preservation conditions on PT measurement and coagulation factor activation. As a result, sample preservation in plastic containers did not affect PT measurement at ambient temperature or in ice, and that in glass containers resulted in a markedly shorter PT for ice than at ambient temperature. There were no changes in coagulation factor Ⅶ activation when samples in plastic containers were preserved at ambient temperature or in ice. However, samples in glass containers showed elevated activities both at ambient temperature and in ice, and this elevation was more prominent in the latter. In this study, no cold-induced activation of coagulation factor Ⅶ in PT measurement was noted when plastic containers were used. However, PT was shorter for some samples when preserved at ambient temperature. Hence, we considered that sample preservation in ice is more appropriate than at ambient temperature.

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Candida albicans is a dimorphic fungus. When pathogenic, C. albicans is in the hyphal form. However, drug susceptibility tests are performed against the yeast form rather than the hyphal form. Therefore, we compared the effects of an antifungal drug on both forms. After 2 hours of incubation, 80% of C. albicans was in the germ tube form. After 4 hours of incubation, 90% of C. albicans was in the hyphal form. No difference in MIC due to the form was observed. When amphotericin B was added when the yeast form was dominant, the switch to the hyphal form was suppressed at all concentrations below the MIC, whereas 5-fluorocytosine(5-FC) and fluconazole(FLCZ) suppressed the switch only at the MIC. However, when 5-FC or FLCZ was added when the germ tube, hyphal form was dominant, the switch to the yeast form was not suppressed at MIC. These findings demonstrate that the drug response depends on the form of C. albicans when the antifungal agents are added.

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AmpC β-lactamase-producing bacteria have emerged worldwide. It is important to detect plasmid-mediated AmpC β-lactamase-producing bacteria, which can spread to other organisms, for surveillance and hospital infection control. Here, we report the case of infection by Klebsiella pneumoniae producing AmpC β-lactamase, which is required for differential diagnosis of infection by Klebsiella pneumoniae producing carbapenemase. A 62-year-old male with pulmonary abscess was referred to our hospital with the chief complaint of hemoptysis in August, 2012. The use of an automated bacterial culture system led to the isolation of carbapenemase-producing K. pneumoniae from the sputum of this patient. The Hodge test, Cica-Beta-Test I, and double disc synergy test with sodium mercaptoacetic acid showed negative results. The samples were sent to National Institute for Infectious Diseases, Japan. After the boronic acid test, the isolate was identified as K. pneumoniae producing DHA-type AmpC β-lactamase. Genetic knowledge and skills are required for the diagnosis and detection of drug-resistant bacteria and accurate diagnosis.

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We report a case of embryonal carcinoma diagnosed by fine needle aspiration cytology of specimens from the left cervical lymph node by immunostaining using liquid-based cytology (LBC). A male patient in his 30s was introduced to our hospital, complaining of swelling of the left cervical region. Left cervical lymph node aspiration cytology revealed neoplastic cells possessing large, irregularly shaped nuclei with a high N/C ratio, and prominent nucleoli, both in the conglomerate and diffuse forms. Embryonal carcinoma was suspected on the basis of LBC of the specimens showing positivity for CD30, Oct3/4, SOX2, and cytokeratin AE1/AE3. CT showed lymph node enlargement from the left cervical region to the upper mediastinum, and from the para-aortic area to the area around the left common iliac artery, whereas FDG-PET examination demonstrated strong FDG accumulation in these enlarged lymph nodes. Weak FDG accumulation was noted in the left testis , but on palpitation and ultrasonographic and CT examinations, no tumor was detected in the testes. It is important to be aware of the possibility that lymph node aspiration cytology and other materials may lead to the diagnosis of embryonal carcinoma. LBC specimens and the appropriate markers in immunostaining are believed to be useful for diagnosis.

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We encountered a case of Clostridium symbiosum infection for which separate culture and identification from positive blood culture bottles were difficult. A 65-year-old female underwent thoracic aorta stent graft interpolation in May 2013. The blood culture prepared in June 2013 was positive only in the anaerobic bottle. Gram-negative rod-shaped cells were observed in a gram stain of the blood culture although their growth was not seen in their subcultures. Then, another blood culture was carried out by adding the first positive culture to human blood, which was then inoculated into fresh blood culture bottles. We entrusted Gifu University to perform direct 16S rRNA genetic analysis of the first blood culture. In the second blood culture, the anaerobic bottle again showed positive culture the following day. Using Brucella HK agar medium (Kyokuto Pharmaceutical), cell growth was observed under anaerobic cultivation the next day. The bacteria showed a negative result in the Ryu test. The property confirmatory test showed that the cells were CV-HK-sensitive, bile-HK-resistant, ES-HK-negative, and H₂S-positive. The results of analysis of biochemical properties, mass spectrometry, and 16S rRNA genetic analysis indicate that the bacterium is C. symbiosum. Positive blood cultures should enable rapid identification of bacteria. Therefore, when it is difficult to identify them in one’s own facilities, it is necessary to entrust an outside agency with their identification as early as possible. For the present bacterium, 16S rRNA genetic analysis and mass spectrometry were useful for the final identification, whereas the Ryu test and property confirmatory test supported its identification.

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To assess the accuracy of daptomycin (DAP) MIC near the breakpoint against Staphylococcus aureus (i.e., MIC=1 μg/mL) by the Etest, MIC tests were conducted using 13 S. aureus test isolates, including non-daptomycin-susceptible isolates, and 3 brands of MHA plates (BD, Eiken and Kyokuto) commercially available in Japan. The results were compared with those obtained by the CLSI reference BMD. S. aureus ATCC 29213 and Enterococcus faecalis ATCC 29212 were used as the quality control (QC) strains. When the DAP MICs were determined by the Etest on Eiken and Kyokuto MHA plates, the MICs of the QC strains were beyond the Etest QC range, and very major errors occurred for 13 test isolates. When the DAP MICs were determined by the Etest on BD MHA plates, the MICs of the QC strains were within the Etest QC range, but a major error occurred for 13 test isolates. For more objective and accurate measurement of DAP MICs against S. aureus, it is necessary to set, not only S. aureus ATCC29213, which indicates the MIC far from the breakpoint, but also the S. aureus strain, which indicates the MIC of the breakpoint, as the QC strain.

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There have been many reports of bacterial identification using a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) system. However, studies of the bacterial identification using the most recent MALDI-TOF MS system (VITEK MS) compared with that using a conventional biochemical identification system are scarce. We compared VITEK MS with VITEK2 (a conventional biochemical identification system) in the identification of 314 clinical isolates. The identification rate at the genus level for VITEK MS (93.6%) was significantly lower than that for VITEK2 (95.9%); however, the identification rate at the species level for VITEK MS (88.9%) was significantly higher than that for VITEK2 (85.0%). VITEK MS might fail to identify enterobacteria owing to inadequate sampling techniques in some cases or insufficient databases of these bacteria. It is necessary for bacterial identification using VITEK MS to take findings of Gram staining and bacterial colonies into consideration. The identification rate for VITEK MS will be increased by improving sampling techniques and upgrading databases.

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We performed basic evaluation studies of the reagents LZtest‘Eiken’MMP-3 (Eiken Chemical Co., Ltd., Eiken) and Panaclear MMP-3 latex (Sekisui Medical Co., Ltd., Sekisui) for matrix metalloproteinase-3 (MMP-3) measurement based on latex turbidimetric immunoassay. The studies conducted by Eiken and Sekisui showed coefficients of variation (CVs) of within-run precision of 1.47–2.75% and 0.89–1.88%, respectively, and CVs of between-day precision of 1.21–3.83% and 2.41–4.45%, respectively. The dilution linearities of both reagents were also good. The correlation for Eiken and Sekisui was excellent: y = 1.07x + 6.96, r = 0.993, n = 142. The current study demonstrated that both reagents showed equivalent performance sufficient for routine clinical use.

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To test for urinary ketone bodies, test strips based on sodium nitroprusside reaction are routinely used. However, the sodium nitroprusside reaction method frequently shows a false positive result owing to a nonspecific reaction with sulfhydryl (SH)-containing reagents including Bucillamine, an antirheumatic drug. Recently, the modified UROPAPER ALPHA 3 “Eiken” ketone test strip^TM (Eiken Chemical, Japan), a urinary test strip that reduces nonspecific reactions, has been developed. In this study, the clinical usefulness of this modified urinary ketone body test strip was evaluated by comparing it with the conventional test strip UROPAPER ALPHA 3 “Eiken” test strip^TM using 292 clinical samples from patients. The concordance rate of these two methods was 89.4% (261/292), and there were 31 (10.6%) unmatched samples. Twenty-five of the 31 unmatched samples showed negative results in the modified UROPAPER ALPHA 3 test and positive results in the conventional UROPAPER ALPHA 3 test. The 31 unmatched samples were finally confirmed to be negative for ketone bodies by an enzyme assay. The unmatched samples were obtained from RA patients treated with Bucillamine. In conclusion, the modified UROPAPER ALPHA 3 “Eiken” ketone test strip^TM effectively reduced nonspecific reactions caused by the SH-group drug Bucillamine, enhancing the effectiveness of routine urinary tests by increasing the specificity of detecting ketone bodies.

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We performed the basic and clinical evaluation of creatinine kinase MB (CK-MB) by isozyme mass quantitation using latex turbidimetry (L-type Wako CK-MB mass, Wako Pure Chemical Industries, Ltd.). The within-run and between-run repeatabilities of the assay were satisfactory, with a coefficient of variation (CV) below 5%. The assay reagent was confirmed to be stable for 15 days. The assay linearity was observed in the range of 1.2–200.0 ng/mL, without apparent prozone phenomenon. The comparison of this assay with a method based on enzyme inhibition immunoassay yielded the linear regression equation: y = 0.97x − 8.6, with a correlation coefficient of 0.986. There was no interference by co-existing substances. The concordance rates for diagnosis of myocardial infarction and nonmyocardial infarction were high in the order of troponin I > CK-MB mass > CK-MB activity, revealing the usefulness of CK-MB mass measurement. The basic performance and clinical validity of CK-MB assay based on this reagent were shown to be satisfactory for routine use in the laboratory.

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The pretransfusion test requires rapidity and high accuracy, and the laboratory staff should have comprehensive knowledge of the test and the patient. It must be carried out anytime by all laboratory staff members with confidence. We have used Ortho^® AutoVue^® Innova for the pretransfusion test to meet these requirements. However, it has a limitation in the continuous loading of reagent red blood cells (R-RBCs) onto the instrument, because long-term on-board loading often results in overconcentration with evaporation and unexpected weak reaction due to the accumulation of physical damage of R-RBCs. In 2013, “E-cap” became available in the Japanese market; thus, there is a possibility to increase the on-board stability for R-RBCs. We tried to evaluate its performance. The result showed that the use of E-cap was effective for maintaining the stability of R-RBCs. It enables continuous loading onto the instrument for up to 24 hours under appropriate maintenance and QC-executed conditions.

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The reactivity of various salts in measuring specific gravity of urine using three kinds of commercial test strips was investigated. The measurement values differed among the kinds of salts and commercial test strips used. Salts were chiefly classified into three groups: salts giving a higher value than NaCl, salts giving a lower value than NaCl, and salts giving the same value as NaCl. Since the chemical species of the acid producing salt changes depending on the pH, the specific gravity of urine is thought to differ depending on the pH even when the salt concentration is the same.

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Various assays are used for human papillomavirus (HPV) detection. The primarily used method of preparing samples for these assays is the split-sample method, in which the sampling device after preparing conventional slides is placed into a vial and a reflex HPV test kit. Another method is liquid-based cytology (LBC), in which an LBC slide is prepared and HPV is detected from the same residual LBC sample. We collected cell samples twice from one patient for the TACAS sampling device and HCⅡ (HPV sampler) then compared the results with those of cytological analysis and HPV DNA detection. HPV DNA detection was performed using HCⅡ. The concordance rate of cytological results between the conventional slide using the HCⅡ device and the TACAS slide was 94.8%, whereas the disagreement rate was 5.2%. HCⅡassay results were concordant between both sample types in 93.1% of patients, whereas the disagreement rate was 6.9%. The HCⅡ assay values showing disagreement were close to the cut-off values. Our results suggest that TACAS is a useful method equivalent to the conventional method using the HPV sampler.

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The tolerance limit of the volume of a syringe in calibration is less than ±3% or ±50 mL of the volume to evaluate the internal quality control in the respiratory function test (RFT). We evaluated the reproducibility and uncertainty using internal quality control data with the calibration syringe. Furthermore, we compared the internal quality control for three years using the average of normals method including "the estimate of the uncertainty of the measurement" using daily precision management data to examine validity as the internal quality control in this study. The uncertainty of measurement values was extremely good with 0.033–0.037 L of the volume. By the average of normals method, we found that both the patient and normal person groups were stable for each month. However, unevenness was clearly observed for each week. We think that the patients are stable when their number is constant. Therefore, this method, which is a management technique including the management of the apparatus as an internal precision control is sufficiently effective.

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It is necessary to define a certain standard for blood cell morphology. Simultaneously, hematological analysis requires high levels of skills and techniques. However, there are very few reports that provide practical standardized reference methods. There are the Japanese Association of Medical Technologists (JAMT) recommendation method and the Japanese Society for Laboratory Hematology (JSLH) proposal method in Japan. We compared both standardized reference methods by literature review before using a set of three trainings. Concerning neutrophils, the proportion of band-form neutrophils increased in the JSLH proposal method using a different basis. Concerning lymphocytes, the morphologies of normal lymphocytes and atypical lymphocytes were not significantly different between the two standardized reference methods. The red cell morphology was similar between these two methods. These results indicate that we should utilize the JAMT recommendation method for classifying neutrophils and examining red cell morphology, and the JSLH proposed method for classifying lymphocytes. In conclusion, a set of three trainings improved cell observation and identification.

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Pneumonia is a common disease and one of the world’s leading causes of death. The objective of this study was to elucidate the microbiological features of community-acquired pneumonia (CAP) and healthcare-associated pneumonia (HCAP). In total, 169 patients (111 CAP and 58 HCAP) were analyzed. Pathogens were identified in 49 (44.1%) of 111 patients with CAP and 33 (56.8%) of 58 patients with HCAP. The occurrence of pathogens was associated with the severity of pneumonia in patients with CAP. However, this feature was not observed in patients with HCAP. Methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and gram-negative Enterobacteriaceae were more frequently detected in patients with HCAP (22.4%) than in patients with CAP (7.2%). The microbiological profile of HCAP was different from that of CAP. Therefore, clinical microbiologists should consider the patient’s background and the severity and type of pneumonia in the identification of causative pathogens.

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Clostridium difficile is the major cause of antibiotic-associated diarrhea (AAD). This organism is a well-known nosocomial pathogen. We evaluated the performance of C. Diff Quik Chek Complete (Quik Chek: Alere Medical Co., Ltd.), which is a rapid immunoassay tool, designed for the detection of both glutamate dehydrogenase (GDH) and Clostridium toxins A and B. In comparison with the culture method, the sensitivity and specificity of this tool for GDH detection were 100% and 96%, respectively. As set forth in the SHEA/IDSA guidelines, GDH detection is useful as a primary screening test for CDAD diagnosis. When no GDH is detected, we must use an abbreviated examination method. In addition, in toxin assay using toxin-negative, culture-positive colonies, growth on CCMA was detected in 17 of the 20 reviews (85%). In the case of GDH antigen positivity, CDI can be diagnosed more accurately by toxin assay with colony growth on CCMA. In the case of GDH antigen positivity, it was decided that such a case should be reported to ICT immediately and infection control should be implemented accordingly.

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We clarified the effect of the integrated electrocardiogram management system on user’s availability and prevention of patient misidentification.　In accordance with the hospital information system update in September 2011, we started paperless operation of all hospital medical services in the National Hospital Organization Kure Medical Center and Chugoku Cancer Center. At that same time, we introduced the integrated electrocardiogram management system, which could connect to all electrocardiographs in the hospital by wireless LAN. In an emergency case, an electrocardiogram was recorded without an electrocardiography order, and patient ID was registered in the recorded electrograph or modified in the electrocardiogram server. It was possible to migrate to the new system using an MFER repository set from the old electrocardiogram filing system of the third party, which had been used for 11 years. The rate of electrocardiogram readings increased after starting the integrated electrocardiogram management system, and the percentage of electrocardiograms from local stations to all electrocardiograms also increased significantly (p<0.05) and reached more than 30%. The percentage of electrocardiograms without registered patient ID decreased 6 months later. In addition, the new system enabled a centralized management of electrocardiograms, allowing the hospital staff to conduct health checks and contributing to paperless operation. In conclusion, the integrated electrocardiogram management system, which could transmit in real time from all electrocardiograms, and the continuous view of the old electrocardiograms proved to be effective in terms of user’s availability and in preventing patient misidentification.

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Because measurement values are affected by hemolysis and turbidity of samples, laboratory technologists should report the state of samples for accurate assessment of measurement values. However, standardization of the evaluation of serum samples has not been satisfactory. Therefore, we explored the present situation of hemolysis and turbidity of samples and their effects on measurement values. In this report, we obtained information about the notation of the onset of hemolysis and turbidity and their effects on measured values by a questionnaire survey particularly on interinstitutional differences and personal differences in visual assessment of samples. The questionnaire survey showed that about 70% of laboratory institutions evaluated hemolysis and turbidity of samples using autoanalyzers. The reports most often indicated hemolysis and turbidity as ‘slight’, ‘moderate’ and ‘marked’. Hemolysis was generally noted at 40–50 mg/dL Hb. At 50 mg/dL Hb, the measured LDH, K and AST levels increased to 29.7% (53.0 U/L), 4.2% (0.16 mEq/L) and 10.2% (2.5 U/L), respectively. Onset of turbidity was generally noted at about 0.02% Intralipos^®, although the measured levels did not show any alterations in the presence of 0.02% Intralipos^®. In this report, we showed that the notation of onset of hemolysis and turbidity differed among laboratory institutions and individual technologists.

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