We established the numerical parameters ALD50 and WaS of the cross-mixing test in APTT prolongation and proposed the WaS-ALD50 method. ALD50 is the parameter that is measured immediately after mixing, and WaS is the parameter that is measured after warming. ALD50 (%) is obtained by dividing the actual value of mixed plasma by the linear value between plasma from a normal person (normal plasma) and plasma from a patient (patient plasma). WaS is the value obtained by calculating the rate of change from immediately after mixing to after warming and subtracting the rate of change in patient plasma from the mixed plasma. We examined 100 plasma samples with prolonged APTT. Of these samples, 38 had the lupus anticoagulant, 14 had coagulation factor deficiency, and 48 had the factor VIII inhibitor. APTT was examined with thrombocheck APTT-SLA using the Coapresta2000 instrument. ALD50 had a sensitivity of 94.7% and a specificity of 92.9% when the cutoff value was calculated with ROC curves of the lupus anticoagulant and the factor deficiency WaS was set to 87.8%. WaS had a sensitivity of 95.8% and a specificity of 96.2% when the cutoff value was calculated with the ROC curves of factor VIII inhibitor and the lupus anticoagulant/factor deficiency WaS was set to 10.2%. The discrimination rate was determined by the WaS-ALD50 method using a matrix table, which showed the discrimination rates to be 94.7% for the ALD50 and WaS LA group, 85.7% for the factor deficiency group, and 95.8% for the VIII inhibitor group as 95.8%, with a mean of 94.0%. In conclusion, the WaS-ALD50 method examined in this study can contribute to the precise analysis of the cause of APTT prolongation.

In obstructive sleep apnea syndrome (OSAS), continuous positive airway pressure (CPAP) therapy is a symptomatic therapy and requires good adherence. Nasal obstruction is one of the causes of difficulty in continuing treatment. Rhinomanometry can be used to objectively assess nasal resistance, which has also been used for the diagnosis of OSAS, but there are only a few reports of its usefulness in improving thrapy adherence. Therefore, this study was conducted to evaluate the relationship between the left-to-right ratio of nasal resistance in rhinomanometry and CPAP therapy adherence in 105 patients who were treated at our hospital. Although bilateral nasal resistance was not associated with subjective nasal obstruction and CPAP therapy adherence, the left-to-right ratio of nasal resistance with subjective nasal obstruction was significantly higher than without (p < 0.01). On the basis of the ROC curve, the optimal cut-off value of the left-to-right ratio of nasal resistance indicating subjective nasal obstruction was 1.88, discontinuation of CPAP therapy was 3.37. CPAP therapy adherence was significantly lower in patients with a left-to-right ratio ≥ 3.37 (p < 0.05). Furthermore, there was a significant tendency to drop out of the therapy (p < 0.05).The subjective nasal obstruction and the left-to-right ratio of nasal resistance may be useful for determining adherence of patients to CPAP therapy.

To clarify the clones of methicillin-resistant Staphylococcus aureus (MRSA) and the trends of Panton-Valentine leukocidin (PVL)-producing strains, we investigated the chronological changes in the percentages of strains carrying a gene encoding PVL (lukF-PV) and the toxic shock syndrome toxin-1 gene (tst), the PCR-based open reading frame typing (POT) score of these toxin-producing strains, and the antimicrobial susceptibility of MRSA isolated at our hospital. In 2001, 2009, and 2017, the percentages of strains carrying lukF-PV were 0%, 5.2% (3/58 strains), and 16.9% (12/71 strains), and the percentages of strains carrying tst were 70.3% (52/74 strains), 36.2% (21/58 strains), and 16.9% (12/71 strains), respectively. The percentage of strains carrying lukF-PV increased, whereas that of strains carrying tst decreased. Twelve of 15 strains carrying lukF-PV and all strains with a POT score of 106-77-119 were considered to be USA300. The dominant POT1 score of strains carrying tst changed from 93 (94.2%, 49/52 strains) to 106 (75.0%, 9/12 strains) between 2001 and 2017. For both toxin genes, the susceptibility rates to clindamycin and minocycline were significantly higher in the group of strains carrying the genes than in the group not carrying them. Changes in the percentages of MRSA strains carrying genes encoding toxins, which were considered to be associated with a clonal shift, were confirmed. The POT method may be useful for the simple prediction of USA300.

We examined the D-dimer level in relation with the thrombus site and thrombus stage in 825 patients who underwent both lower extremity vein ultrasonography and D-dimer level determination for the diagnosis of deep vein thrombosis (DVT). DVT was observed in 216 patients (26%). The thrombus sites were of the central type (85) and peripheral type (131), and the thrombus stages were the acute (56) and chronic (160) stages. The median D-dimer levels in the DVT and non-DVT groups were 8.8 μg/mL and 2.1 μg/mL, respectively. In 137 patients with D-dimer levels in the reference range, no DVT was detected. D-dimer levels were 9.8 μg/mL in DVT patients with the central type and 7.6 μg/mL in those with the peripheral type, and 10.0 μg/mL in those in the acute stage and 7.9 μg/mL in those in the chronic stage; these values were not significantly different. When compared between outpatients and inpatients, the acute stage was significantly more prevalent than the chronic stage in outpatients (p = 0.003). Furthermore, when we followed the course of thrombus and D-dimer level, the D-dimer level tended to decrease over time in the group wherein the thrombus stage did not advance. Consequently, we confirmed that the low D-dimer level is useful for excluding the existence of thrombus, and the D-dimer level may be helpful in estimating the thrombus stage in outpatients. Moreover, because of the low specificity of the D-dimer level for the diagnosis of DVT, it will be effective to confirm the time course of the D-dimer level rather than the D-dimer level at one time.

Anti-phospholipid antibodies (aPLs) do not bind directly to the negatively charged phospholipid itself but rather to complexes of the phospholipid and phospholipid-binding proteins, and their most common antigenic targets are β₂-glycoprotein I (β₂GPI) and prothrombin (PT). Therefore, multiple aPLs to β₂GPI and PT must be measured by ELISA to accurately diagnose antiphospholipid syndrome (APS). In this study, we developed a new ELISA kit that can detect more aPLs for the first screening test for APS diagnosis. Two laboratory-made ELISA kits were developed by combining immobilized cardiolipin (CL) with two epitope-providing proteins, ABP and ABS. We measured the level of each aPL in 140 plasma samples from APS patients (n = 63) and healthy subjects (n = 77) using our two ELISA kits and 10 commercial ELISA kits. We performed the receiver operating characteristic (ROC) curve analysis on the absorbance level in mOD detected by aCL/ABP and aCL/ABS ELISA using the 140 plasma samples, and we set the cut-off values for our two ELISA kits. The positivity rate for aPLs in the APS patient group was higher for the two laboratory-made ELISA kits than for the commercially available ELISA kits. ROC curve analysis showed that the accuracy of APS prediction based on aCL/ABS-ELISA results was 0.73 in terms of the area under the ROC curve (AUC), whereas that based on aCL/ABP-ELISA results was 0.91. These results suggest that aCL/ABP-ELISA is useful as the first screening test for APS diagnosis.

Blood potassium (K) fluctuations not only depend on renal function, but also on other factors such as hemolysis. The aim of this research is to replicate and detect transient hyperkalemia without any of these problems, but with the suspected effect of a potassium-rich diet, in an actual clinical case that the researchers encountered. Twelve healthy volunteers with informed consent ingested a potassium-rich diet, which is similar to the diet of the patient of interest. Serum K, urinary K and urinary creatinine (CRE) levels before meal intake and 1 and 2 h after the meal intake were measured. In two of the 12 participants, the serum K level increased by 0.7 mmol/L at 1 h after the meal intake, and urinary K/CRE increased by 60 mmol/g·CRE 2 h after the meal intake. In all 12 participants, a significant increase in serum K level was observed 1 h (*p < 0.05) and 2 h (**p < 0.01) after the meal intake, and an increase in urinary K/CRE 2 h* after the meal intake. An increase in serum K level of more than 0.3 mmol/L was seen in seven of the 12 participants. In these participants, a higher urine K/CRE 2 h after the meal intake and a lower urinary K excretion level 1 h after the meal intake were observed, which suggest delayed K excretion. In this study, we observed an increase in serum K level following meal intake in healthy individuals. In hyperkalemic patients with discrepancies in clinical features, it is important to check the contents of their diet and time after consumption before analysis.

The antinuclear antibody (ANA) test is clinically important for the diagnosis of autoimmune diseases such as connective tissue diseases and autoimmune hepatitis. The aim of this study was to evaluate the clinical utility of a screening test for eight disease-specific ANAs using a chemiluminescence enzyme immunoassay (CLEIA-ANA) in routine ANA tests and comparing the results with those of an indirect immunofluorescence assay (IF-ANA). In this study, we analyzed patients with rheumatic, dermatological, and gastrointestinal diseases because ANA tests are clinically important for these disorders. The concordance rate between CLEIA-ANA and IF-ANA (1:40) was low (41.9%) in patients with gastrointestinal diseases, suggesting that autoantibodies detected by IF-ANA alone were clinically important. The concordance rates between CLEIA-ANA and IF-ANA (1:160) were 72.8% in patients with rheumatic diseases and 77.5% in patients with dermatological diseases. CLEIA-ANA efficiently detects eight disease-specific ANAs including anti-SS-A antibody, which is frequently overlooked in patients with rheumatic and dermatological diseases when using IF-ANA. The positivity rate for a dense fine speckled (DFS) staining pattern in sera from CLEIA-ANA-negative/IF-ANA-positive patients (1:160) was significantly higher in patients with dermatological diseases (17/45) than in those with rheumatic diseases (5/40) (p = 0.0123). Of 17 patients with dermatological diseases with a DFS staining pattern, 16 were positive for the anti-DFS70 antibody, which is frequently detected in those with skin diseases and in healthy subjects. Indeed, more than half of the 16 patients had a skin disease. In summary, CLEIA-ANA efficiently detects eight disease-specific ANAs in routine ANA tests of patients with rheumatic and dermatological diseases, although in some other patients, such as those with gastrointestinal diseases, they are undetectable by CLEIA-ANA owing to solid-phase antigens.

Lung function test reference values are determined on the basis of gender, age, and height. Therefore, they must be reviewed regularly to accommodate changes in the living environment. In this study, we evaluated the relative reliability and systematic bias associated with vital capacity (VC), forced vital capacity (FVC), and forced expiratory volume in one second (FEV₁) after the lung function test reference values reported in 2001 by the Japanese Respiratory Society were revised in 2014 (JRS2014). This study is aimed at determining the errors associated with the previous values. We also evaluated the lower limit of normal (LLN) recommended by the American Thoracic Society. On the basis of the Landis criteria, the relative reliability of these revised reference values was “Almost Perfect.” The reference values were changed as follows: VC, −0.55% to 7.59%; FVC, −2.45% to 6.25%; and FEV₁, −8.48% to 3.30% in males, and VC, −1.08% to 10.33%; FVC, −0.44% to −14.55%; and FEV₁, −2.28% to −14.70% in females. Using the JRS2014 reference values and LLN to detect patients with decreased VC led to a significant increase in the number of detections. The use of LLN to detect airflow obstruction in patients resulted in a significant increase in the number of detections in males but not in females. When changing reference values, it is important to determine the resultant effect after the change. Furthermore, the use of a new factor for the early detection of respiratory diseases should be considered.

Leber’s hereditary optic neuropathy (LHON), one of the mitochondrial diseases, was specified as an intractable disease in 2015. The first three mutations (m.11778G>A, m.3460G>A, m.14484T>C) account for approximately 90% or more of the mitochondrial DNA mutations present in LHON. To detect the primary and other candidate LHON mutations registered in the LHON mutations category of MITOMAP, using Minor Groove Binder (MGB-probe), we measured three primary mutations and conducted sequence analysis at 36 points in nine regions. The results clarified that this type of analysis required time and cost of reagents and generated vast data. In light of the above finding, aiming to improve the investigation efficiency, we conducted the mitochondrial DNA gene investigation in accordance with the diagnostic classification and closely examined the obtained results. Using LHON-like standards in clinical diagnosis prepared by doctors, we judged the breakdown of sixty-three cases. The first three mutations were level L1 for one case, level L2 for nine cases, and level L3 for ten cases, suggesting that the detection rate becomes higher as the diagnostic level increases. The breakdown of nine other mutations showed mutations of level L1 for three cases, level L2 for three cases, and level L3 for four cases. Thus, we achieved labor-saving, shortened reporting frequency (days), and concurrent analysis of the primary and other mutations in the investigation by introducing the mitochondrial DNA gene investigation in accordance with the diagnostic levels in cooperation with the requesting physician. For this reason, the analysis method reported in the present study is expected to be clinically useful in ensuring definitive LHON diagnosis as per the 2015 revision of “Certification Criteria for Intractable Diseases.”

To efficiently isolate methicillin-resistant Staphylococcus aureus (MRSA) using culture media, we evaluated the performance of five media for the detection of Staphylococcus aureus, and we compared the performance of seven media for the detection of MRSA with that of the drug susceptibility test. Sixty Staphylococcus strains (28 MRSA strains, 17 methicillin-susceptible Staphylococcus aureus (MSSA) strains, and 15 non-S. aureus strains) were used for evaluation of culture media. As a result, the sensitivity and specificity of culture media for the detection of S. aureus were 91%–100% and 87%–100%, respectively. Moreover, in comparison with the drug susceptibility test, the positive and negative predictive values for MRSA were 90%–100% and 94%–100%, respectively. We recommend that the properties of media used to efficiently isolate MRSA should be clarified in future studies.

The hepatitis B virus (HBV) surface antibody (HBsAb) is used for the diagnosis of HBV infections and is a marker that appears after vaccination. We evaluated the second-international-standard-based reagent kit for anti-hepatitis B surface antigen (anti-HBs) immunoglobulin (NIBSCcode: 07/164), Lumipulse Presto HBsAb-III (Lumipulse 2nd reagent) and compared it with Lumipulse Presto HBsAb-N (Lumipulse 1st reagent). Within-run and between-run reproducibility precisions were 1.6–3.0% and 1.7–3.8%, respectively. The obtained diluted linearity and lower limit of detection were 1,000.0 and 0.9 mIU/mL, respectively. The correlation coefficient (r) between Lumipulse 2nd reagent and Lumipulse 1st reagent was 0.997. The cutoff value (10.0 mIU/mL) for the concordance rate of the Lumipulse 2nd and 1st reagents was 100%. The basal performance of the Lumipulse 2nd reagent was satisfactory, and it could be used for measurement with high sensitivity.

We conducted a basic study of individual differences in the preparation of the prothrombin freeze-drying reagent Coagupia^® PT-N (PT-N) and the liquid PT measurement reagent Coagupia^® PT-Liquid (PT-L). For both whole pipettes and micropipettes, significant differences were observed in the measured values among medical technicians when reagents were adjusted and measured with a pipette. In the basic performance evaluation of PT-L, which does not require adjustment, good results were obtained for accuracy, simultaneous reproducibility, onboard stability, dilution linearity, and detection limit, and the effects of interfering substances were determined. Bilirubin, conjugated bilirubin, hemoglobin, and chyle had no effect up to the final concentration, and heparin had no effect up to 0.8 U/mL within the normal PT range and 1.0 U/mL within the abnormal PT range. The correlation between PT-L and PT-N was good with a regression with y = 0.95x + 0.58 and a correlation coefficient r = 0.99 in% PT activity. Coagupia^® PT-L is considered to be a highly convenient reagent that is expected to contribute in clinical settings because there are no errors associated with reagent preparation, and it can be used immediately without requiring time for preparation.

Some species of the genus Aeromonas carry genes that encode carbapenemase in their chromosomes; these species are classified under Ambler classification class B2. We experienced treating a patient from whom a carbapenem-resistant Aeromonas isolate showed a discrepancy between the results of VITEK2, an automatic analyzer for drug susceptibility testing, and the disc diffusion method (E test). Therefore, using carbapenem-resistant strains of the genus Aeromonas, we examined the difference in drug susceptibility results among different models of an automatic analyzer and examined the carbapenemase confirmation test results. Carbapenem-resistant Aeromonas hydrophila and Aeromonas veronii detected at our hospital were tested for drug susceptibility using three models of the automatic analyzer, namely, VITEK2, MicroScan WalkAway, and RAISUS ANY, and the results showed discrepancies. Among the automatic analyzers used, VITEK2 could detect carbapenem resistance best. By conducting a carbapenemase confirmation test, we found that carbapenem drugs may show false results in Aeromonas susceptibility tests. We speculate that it will lead to treatment and nosocomial infection control.

UriSwab is a collection device for urine cultures, which contains boric acid as a preservative agent, making it possible to preserve urine samples until processing in the laboratory. UriSwab is easy to use and, more importantly, lessens the risk for excessive growth or loss of pathogens. However, in Japan, no studies have been conducted on its use and sample stability during storage. We determined the collection condition of urine absorbed on the UriSwab sponge applicator and tested the viability of pathogens in the urine using Escherichia coli, Enterococcus faecalis, and Neisseria gonorrhoeae ATCC strain. No significant changes in the collection condition were observed. Therefore, we determined 60 s as the optimal collection condition due to the minimum standard deviation. Compared with a sterile tube, UriSwab significantly suppressed the overgrowths of E. coli and E. faecalis during storage at 25°C (p < 0.01) and prevented the decimation of N. gonorrhoeae during storage at 4°C (p < 0.01). Findings of our study suggest that UriSwab is a more reliable sample receptacle than sterile tubes.

Zinc deficiency causes a wide variety of pathologies, including taste disorders, immunological disorders and exacerbation of various diseases, which can be corrected by adequate zinc supplementation. Therefore, it is important to measure serum zinc levels correctly and promptly and to control the serum zinc level. Our hospital has been testing for serum zinc levels since July 2019. The aim of this study was to evaluate the effect of changing from external to in-hospital serum zinc tests. The study included 4,722 patients whose serum zinc levels were measured at our hospital between January 2019 and February 2020. We compared the situation before and after the introduction of the test in the hospital, which increased the number of patients (both inpatients and outpatients) tested. In inpatients, there were no significant differences in serum zinc levels and prescribed doses of Nobelzin between the time before the introduction of the test and that after the introduction. However, in outpatients, serum zinc levels were lower, and the prescribed dose of Nobelzin was also predominantly lower. This could be attributed to the fact that the serum zinc level can be determined on the day of outpatient treatment by the in-hospital tests, which enabled us to adjust the prescribed dosage of Nobelzin. These results suggest that the in-hospital serum zinc tests will assist physicians in their practice and contribute to reducing the burden on patients.

For specimens that exceed the formalin fixation time recommended in the “Regulations for Handling Pathological Tissue Specimens for Genome Medical Treatment”, deterioration of nucleic acid quality is a concern. We examined the fixation conditions for maintaining good nucleic acid quality. We also examined the effect of the fixation conditions on histopathological diagnosis. We used sections of the unfixed lung, thyroid gland, and ovary as specimens. They were fixed under the following 11 conditions: “Fixed at RT for 1, 3, and 7 days”, “Refrigerated immediately after fixing and stored for 3 to 7 days”, “Fixative partially replaced with alcohol after fixing at RT for 1 day and stored at RT for 2 to 6 days”, “Fixative completely replaced with alcohol after fixing at RT for 1 day and stored at RT for 2 to 6 days”, and “Refrigerated after fixing at RT for 1 day and stored for 2 to 6 days”. Nucleic acid fragmentation was evaluated in terms of ΔCT value, and results of HE staining and IHC were also evaluated. Specimens that were “fixed at RT for 3 and 7 days” were found to have QC values below the recommended values. Under conditions other than “fixed at RT for 3 to 7 days”, the QC value was equivalent to that under “fixed at room temperature for 1 day”. For both HE staining and IHC, there was no problem with the staining results under all the set fixation conditions. It was considered that good nucleic acid quality could be maintained except for “fixed at RT for 3 to 7 days”. It was also shown that these fixation conditions do not adversely affect the histopathological diagnosis.

Although rapid identification tests using a mass spectrometer are becoming mainstream, such tests are not applicable in all facilities because some of the facilities do not have a mass spectrometer. M35-A2 published by the Clinical and Laboratory Standards Institute (CLSI) details rapid and simple identification methods for bacteria and yeast. In this study, the identification method for Escherichia coli described in the CLSI guidelines (CLSI method) was verified with the method of York et al. (original method), which is the basis of the CLSI method, using clinical isolates. Of the 543 strains (E. coli strains, 478; non-E. coli strains, 65) of gram-negative bacilli that were oxidase-negative and spot indole-positive, all E. coli strains were correctly identified by both methods and 99% of these strains could be identified within 30 minutes. However, six non-E. coli strains identified using the CLSI method and one non-E. coli strain identified using the original method were misidentified as E. coli. In more detail, one strain of PYR test-negative Klebsiella oxytoca was misidentified by both methods, and five strains of β-hemolytic Morganella morganii were misidentified only by the CLSI method. These results suggest that the original method was more suitable for routine laboratory test. We hope that this identification method is used meaningfully according to the situation of each laboratory.

Hepatitis E virus (HEV) is the causative pathogen of hepatitis E, and genotypes 3 and 4 strains are detected in Japan. Since highly pathogenic genotype 4 strains are more frequently detected in Hokkaido than in other regions, we developed a multiplex real-time reverse transcription (RT) polymerase chain reaction (PCR) assay to rapidly discriminate between genotypes 3 and 4 (D-PCR). To improve the sensitivity of D-PCR to genotype 4, we compared the performance between QuantiTect Probe RT-PCR Kit (conventional reagent) and Reliance One-Step Multiplex RT-qPCR Supermix (BIO-RAD, A reagent) using HEV RNA-positive samples, the HEV RNA concentrations and genotypes of which were already determined. The linear dynamic range of A reagent for genotype 3 was similar to that of the conventional reagent, whereas that for genotype 4 was 10 times wider than that of the conventional reagent. The PCR efficiencies using the conventional reagent and A reagent were respectively 109.9% vs. 108.3% for genotype 3 and 89.7% vs. 97.1% for genotype 4. The sensitivities of PCR using the conventional reagent and A reagent when using 1,000 μL of plasma were respectively 20 IU/mL vs. 19 IU/mL for genotype 3 and 66 IU/mL vs. 16 IU/mL for genotype 4. As the efficiency and sensitivity of D-PCR have been improved by using A reagent, D-PCR can rapidly determine genotypes at an earlier stage than before, especially for individuals infected with the highly pathogenic genotype 4 strains, and promptly provide genotype information useful for subsequent treatments.

Small colony variants (SCVs) constitute a slow-growing subpopulation of bacteria with distinctive phenotypic and pathogenic traits. Phenotypically, SCVs have a typical colony morphology and unusual biochemical characteristics. Therefore, it is difficult to detect and identify SCVs. It is suggested that SCVs are not detected in the conventional screening agar for methicillin-resistant Staphylococcus aureus (MRSA). We compared growth performances of SCVs-MRSA in two culture media: CHROMagaer MRSA (CHROMagaer) and NISSUI plate X-MRSA agar (X-MRSA). We also compared the usefulness of these media with that of the medium used in a routine laboratory test. Method: (1) We examined the growth support ability by the Miles & Misra method. The strains used in the examination were isolates of three SCVs-MRSA strains and one normal MRSA strain and type strains of MRSA and MSSA. (2) For 50 clinical specimens, we compared the MRSA detectability. Result: (1) The growth support abilities of the two culture media were similar. One of the SCVs-MRSA strains required 48 h for growth in both culture media. The two other SCVs-MRSA strains showed the same growth as the normal MRSA in 24 h. (2) After 24 h of incubation, the sensitivity, specificity, positive predictive values (PPV), and negative predictive values (NPV) were all found to be 100% for the two culture media. After 48 h of incubation, the sensitivity, specificity, PPV, and NPV were 100, 91.7, 33.3, and 100 for CHROMagaer and 100, 93.8, 40.0, and 100 for X-MRSA, respectively. Conclusion: With the two culture media, the detectabilities of SCVs-MRSA and MRSA in a routine laboratory test were similar. We conclude that SCVs-MRSA can be easily detected using the two culture media.

The blood culture positivity rate is affected by blood sample volume, and the American Society for Microbiology guidelines (CUMITECH) recommends 20–30 mL of blood for a single sample. The optimal blood sample volume for aerobic and anaerobic culture vials used with the BD Bactec^TM FX system is 8–10 mL (the measurable blood sampling volume ranges from 3 to 10 mL). If one set comprises one aerobic culture vial and one anaerobic culture vial, the CUMITECH recommendation may not be met when using only one set of vials or a single blood sample volume in the measurable range. We analyzed 3,841 sets of blood culture vials submitted during a 2-year period between July 2014 and June 2016 for variations in the positivity rate with changes in blood culture and blood drawn volumes using laboratory results from our hospital. We observed a significant decrease in the positivity rate with blood volumes of 4.0 mL or less in anaerobic culture vials, suggesting that false negatives may occur with insufficient blood volumes in the measurable range.

We detected an anti-K natural antibody from the plasma of an 80-year-old Japanese woman who had no history of red blood cell transfusion. We considered that it was an anti-K natural antibody, because the result of an unexpected antibody screening test performed nine months earlier was negative for the antibody. It showed dithiothreitol (DTT) treatment sensitivity; therefore, we considered that it was of the immunoglobulin IgM type. However, it showed reactivity at 37°C. In addition, it was detectable by the saline-indirect antiglobulin test (saline-IAT) for about three weeks. The characteristics of the anti-K natural antibody in several previous reports are partly different from those in our case, that is, the cause of the antibody production was considered to involve bacterial species. This suggests the possibility that the mechanism was exclusively bacterial involvement.

We report a case of catheter-associated bloodstream infection caused by the Mycobacterium fortuitum complex of two different strains that were in a colony form. The patient was a 61-year-old female, whose chief complaints were fever and lassitude. The blood culture became positive in four days of illness, and the Gram stain of the blood sample showed Gram-positive bacilli. Owing to our suspicion of Mycobacterium species, we conducted Ziehl–Neelsen staining, which revealed Mycobacterium species. The Mycobacterium species of two different strains that were in a colony form grew in 5% sheep blood agar, and both strains were detected from an encrustation (crust) on the central venous catheter surface and from the implantable central venous access port. The catheter-associated bloodstream infection caused by rapidly growing mycobacteria was suspected from the speed of growth. The two strains were identified as M. fortuitum by DNA–DNA hybridization and as a M. fortuitum complex by mass spectrometry. The results of susceptibility tests of both strains were the same. Treatment with Imipenem/Cilastatin (IPM/CS) and Amikacin (AMK) was continued for six weeks, after which, the patient’s symptoms resolved. The identification of the nontuberculous mycobacteria and the choice of the method for susceptibility tests are important. In intractable or rare nontuberculous mycobacteria cases, the information exchange with the doctor in charge is important.

We reviewed irregular antibody information acquired from other facilities before transfusion and investigated whether the information will be useful for blood supply. Of seven patients, six visited our hospital carrying the antibody information, and the remaining patient presented a card indicating that the patient had an irregular antibody. The advantages of acquiring information from other facilities are as follows: shortening of the time to identify irregular antibodies and to decide the blood type to be selected or to judge whether it can be handled in their own facility, and also the prevention of the delayed hemolytic transfusion reaction caused by the absence of certain antibodies. On the other hand, problems such as the method of communicating information and the method of utilizing the information after receiving it were not defined, so it is difficult to judge the situation when the information acquired from other facilities is not consistent with the result from their own laboratory. Moreover, in this study, we found that there are few patients carrying the card with irregular antibody information, as suggested by the Ministry of Health, Labor and Welfare. In the near future, it is hoped that the use of this card will be more widespread.

Prostatic small cell carcinoma is a high-grade neuroendocrine tumor with characteristic morphological and immunohistochemical features. A 76-year-old male presenting with high serum PSA (prostate specific antigen) levels was diagnosed as having conventional prostatic adenocarcinoma. Normalization of serum PSA levels was achieved by hormonal therapy. However, atypical cells with hyperchromatic nuclei, inconspicuous nucleoli, scant cytoplasm and nuclear molding were detected in urinary sediment by conventional urinalysis about a year later. Atypical cells were positive for synaptophysin, which was indicative of prostatic small cell carcinoma. Small cell carcinoma of the prostate is rare and has a poor prognosis, so it is important to recognize its cytological characteristics.

We report a case of Neisseria meningitidis sepsis that triggered purpura fulminans. The patient was a woman in her 80s. She was brought to our hospital by ambulance because of fever and disturbance of consciousness. Her laboratory findings showed severe inflammatory changes. On physical examination, subcutaneous induration, redness, and purpura of the right lower leg were detected. Chest CT scan showed an infiltrative shadow in the apex area of the left lung. We diagnosed her as having sepsis associated with a soft tissue infection or pneumonia, and the administration of antibiotics (meropenem (MEPM) and vancomycin (VCM)) was started. Gram-negative diplococci were found in blood and sputum cultures. After isolating the diplococcal cells in chocolate agar, a light-gray colony was detected. N. meningitidis was initially suspected from the Gram staining results, but we did not always have a ready supply of meningococcus antigen reagent, so we were not able to confirm it. The result of Gram staining indicated N. meningitidis. We finally diagnosed her as having purpura fulminans associated with sepsis on the basis of N. meningitidis identification. The antibiotics were changed to ceftriaxone (CTRX), and improvement of the inflammation was confirmed. N. meningitidis is a bacterium that is infrequently detected. However, N. meningitidis is highly pathogenic and needs to be detected rapidly. Thus, an examination system for N. meningitidis should be urgently developed.

Granular cell tumor (GCT) is rare and shows neuroectodermal differentiation. GCT in most cases arises from the tongue and dermis. Herein, we report a case of GCT diagnosed by fine needle aspiration cytology (FNAC). A woman in her 50s underwent left total mastectomy and rectus abdominis myocutaneous flap owing to left breast cancer. Ten years later, ultrasonography of the reconstructed breast showed a low-echoic mass of 12 mm diameter, and FNAC was performed. In the FNAC specimens, there were numerous granular materials in the background, and ovoid to polygonal atypical cells appeared singly or in clusters. The atypical cells showed a low N/C ratio, bland nuclei, small nucleoli, and cytoplasm with abundant eosinophilic granules. The cytodiagnosis of GCT was carried out. Core needle biopsy of the mass showed atypical cells with the same morphology as the atypical cells seen in the FNAC specimens, which formed nests with a syncytial appearance. Immunohistochemistry demonstrated that the atypical cells were positive for S100, calretinin, and inhibin, consistent with GCT. In the present case, FNAC plays an important role in the diagnosis of GCT.

In Japan, the number of patients suffering from an invasive infection caused by Haemophilus influenzae type b (Hib) has decreased markedly because of mandatory Hib vaccination beginning at two months of age under the Preventive Vaccination Law. However, the epidemiology of adult invasive Hib infection remains poorly understood because of the limited number of reports. We encountered a case of purulent knee arthritis and septic shock caused by Hib in an adult male. The patient, in his thirties, had Dubowitz syndrome as a comorbidity. He visited the Department of Orthopedic Surgery for knee joint pain and difficulty in walking and was subsequently referred to our hospital because of suspected septic shock due to the purulent arthritis of the left knee. The patient was started on antibiotic therapy because of a high level of inflammatory response, as shown by his blood test results, and fluid retention in the left knee joint, as seen in his CT scans. The arthritis improved within three days, and the patient was discharged on the 21st day of being admitted to the hospital. Microbiological tests revealed H. influenzae in blood culture and joint puncture fluid, with its capsular type determined to be type b. Thus, in the presence of Dubowitz syndrome as the primary disease, the infectious disease may be exacerbated by host factors, such as compromised humoral immunity. Although the incidence of invasive Hib infection has recently decreased because of a public subsidy program for Hib vaccination, an effective vaccination strategy should be established for adults who had undergone splenectomy or with underlying diseases that cause humoral immunodeficiency, as well as for infants.

The sigmoid-shaped interventricular septum is the sigmoid-shaped basal septum protruding into the LV cavity. The AS angle (aortoseptal angle: the angle between the anterior aortic wall and the interventricular septum) in patients with the sigmoid-shaped interventricular septum is smaller than that in normal subjects. The causes of the sigmoid-shaped interventricular septum are aging and left ventricular outflow tract obstruction (LVOTO), which is rare. We report the case of a patient with the sigmoid-shaped interventricular septum with LVOTO and exertional dyspnea. In this patient, cibenzoline administration improved LVOTO markedly. In our 370 consecutive patients, six (1.6%) showed significant pressure gradients (PG) > 30 mmHg. Patients with PG > 30 mmHg showed significant narrowing of LVOT. Echocardiographic examination including Valsava maneuver is useful for symptomatic patients with LVOT and narrowing of the sigmoid-shaped interventricular septum.

Rapidly progressive glomerulonephritis (RPGN) is a condition of the kidney characterized by a rapid loss of renal function with acute or subclinical gross hematuria or proteinuria. On urinary sediment examination, glomerular hematuria due to glomerulonephritis and other conditions often shows various types of cast, including glomerular-type red blood cells (RBCs) and RBC cast. We encountered four cases of RPGN with difficulty in the detection of glomerular-type RBCs on urinary sediment examination. Their common findings include: (1) a mixture of RBCs in a dehemoglobin status, with little variety and difference in size in the overall pattern of appearance; (2) the appearance of various types of cast, including RBC cast, granular cast, and wax cast; (3) a marked decline in renal function, as indicated by a low estimated glomerular filtration rate (eGFR); and (4) strong positivity for protein and occult blood in qualitative urinary examination. In two cases, morphological information on RBCs (RBC-Info.) of UF-1000i (Sysmex) was “Mixed?”. On the basis of these results, it was possible to infer the pathogenesis and suspect glomerular hematuria. With severely impaired renal function, the RBC morphology in the urinary sediment may not show any change despite glomerular hematuria, and care should be taken in determining the RBC morphology. In addition, if glomerular hematuria is suspected on the basis of the pattern of the urine sediment image (RBC morphology, appearance of various types of cast) and other test results, it is important to perform a detailed speculum examination considering the possibility of appearance of a few RBC casts associated with glomerular hematuria.

We experienced treating two cases of suspected Kounis syndrome with ST-segment elevation and electrocardiographic changes associated with anaphylactic shock. Case 1: A 70-year-old woman was transferred to a critical care center owing to anaphylactic shock immediately after using a contrast medium. At the time of admission, neither her consciousness level JCS I-3 nor blood pressure could be measured, and electrocardiography showed ST-segment elevation in leads II and III and aVF, and ST-segment depression in leads V1 to V5. Although ACS was suspected, no significant stenosis of the coronary arteries or ACS was observed. From the above, it is considered that the ST-segment elevation and depression in electrocardiography, which indicated anaphylactic shock, was caused by the contrast medium. Case 2: A 59-year-old man who took PL granules and Flomox after seeing a local doctor showed an anaphylactic shock, and electrocardiography showed ST elevation of leads II and III and aVf. Since acute coronary syndrome was also suspected, he was referred to our hospital. No significant stenosis was observed on coronary angiography, and the acetylcholine tolerance test showed negative results. In the lymphocyte transformation test, positive reactions to PL granules and Flomox were observed; thus, it was concluded that the electrocardiographic changes were due to anaphylactic shock. Kounis syndrome is a rare disease that is triggered by an allergic reaction and causes acute coronary syndrome. If a patient presents with a serious condition, the possibility of Kounis syndrome should be taken into consideration when conducting examinations, treatments, and observations.

The Nutrition Support Team (NST) in our hospital consists of doctors, nurses, pharmacologists, registered dietitians, rehabilitation staff, and clinical laboratory technologists. Our mission is to improve patients’ nutritional status. To achieve our mission, we evaluate the patients’ nutritional status using the periodical round and administer a proper nutritional therapy. Although NST intervention has been performed in patients in the chronic phase, it has also been applied to patients in the acute phase. Eighty patients (48 males, 32 females; median age, 71 years) who received NST intervention at least twice between January and June 2016 were candidates for this retrospective analysis. We excluded patients who had died during their admission. After NST intervention, the levels of serum albumin, total cholesterol, and C-reactive protein, total lymphocyte counts, the scores of controlling nutritional status (CONUT), and the results of subjective global assessment were significantly improved (p < 0.01). Multiple correlation analysis showed that low levels of serum albumin before NST intervention (p < 0.01) and in elderly patients (p < 0.01) led to high CONUT scores after NST intervention and a maintained malnutrition status. Moreover, multiple correlation analysis also showed that a long NST intervention was related to the experience of operation (p < 0.01) or infection (p = 0.014) before the end of the NST intervention. These results indicated that the low levels of albumin before NST intervention and in elderly patients may prevent the recovery from malnutrition, and the experience of operation or infection might prolong the duration of NST intervention.