The Revised International Staging System (R-ISS) is widely used to stage multiple myeloma (MM). It classifies stages I–III based on albumin, β₂-microglobulin, LD levels, and chromosomal abnormalities. Many laboratories outsource chromosomal testing, often delaying stage determination for several days. We explored rapid staging methods using calcium (Ca), creatinine (Cr), and hemoglobin (Hb) levels as diagnostic parameters for MM. This study included 88 untreated patients with symptomatic MM. As the stage progressed, Ca and Cr levels were higher and Hb levels were lower. Cr levels varied by sex, prompting an examination of the estimated glomerular filtration rate (eGFR), which also significantly decreased as the stage advanced. The percentage of patients in each stage was examined for Ca, Cr, Hb, and eGFR according to cut-off values for MM diagnosis, and the results showed that more than 90% of stage I patients were within the cut-off value for all parameters. However, determining the stage using a single parameter proved challenging as values varied significantly across parameters for stages II and III. Therefore, we developed and validated a scoring system that combines these parameters for stage classification. Cutoff values for stages II and III, derived from ROC analysis, were 2 (with 93.3% sensitivity and 100% specificity) and 5 (with 100% sensitivity and 75% specificity), respectively, indicating significantly higher scores with advanced staging. The agreement rate between the R-ISS and our system was 78.4%, with complete concurrence in stages I and III. In conclusion, our system allows for earlier staging of MM compared to traditional methods. Cutoff values used to diagnose MM.

Objectives: In this study, we: 1) attempted to ascertain the effects of formalin vapor exposure on the staining and cell morphology of fixed cytology specimens; and 2) investigated methods of improving the staining. Study Design: We examined smears of cytosol suspensions prepared from uterovaginal secretions. The specimens were exposed to formalin vapor by placing them in a sealed container with a Kim towel soaked in 1 mL of formalin. We also examined the potential of sodium bicarbonate (NaHCO₃) solutions for restoring or improving the staining and cell morphology of formalin vapor-exposed specimens. Results: Exposure to formalin vapor deteriorated the Papanicolaou staining. Among the tested conditions, treatment with 10% aqueous NaHCO₃ solution for 3 h at 60°C improved the staining of the formalin vapor-exposed specimens the most. Conclusion: We demonstrated that exposure to formalin vapor deteriorated the Papanicolaou staining, and that NaHCO₃ solution could partially restore the staining of the specimens. However, cell detachment is an issue that should be considered when treating specimens with aqueous NaHCO₃. Our results indicated that it is imperative for cytology specimens be transported separately from histopathology specimens; alternatively, they should be placed in a sealable plastic bag.

Lupus anticoagulant (LA) is defined as an immunoglobulin that inhibits phospholipid-dependent clotting reactions without inhibiting the activity of individual clotting factors. Detection of LA activity by phospholipid-dependent coagulation assay is one of the laboratory test findings in the antiphospholipid syndrome (APS) diagnostic criteria. among LA screening tests, APPT-based cross-mixing tests are common tests in clinical laboratories. The cross-mixing test differentiates whether the prolonged clotting time is due to a coagulation factor deficiency, coagulation factor inhibitor, or LA, based on the coagulation plot pattern. Recent clinical studies suggest that patient plasma on direct oral anticoagulant (DOAC) therapy may influence LA determination by APTT-based cross-mixing tests. This study investigated the effects of four DOACs (dabigatran, rivaroxaban, edoxaban, and apixaban) on APPT-based cross-mixing tests, the efficacy of DOAC removers, and the usefulness of confirmatory testing using Staclot LA. As a result, many of the DOAC model therapy plasma samples were judged to be false positive for LA, and treatment with a DOAC remover may not have led to correct results. On the other hand, an LA confirmation test using the addition of hexagonal (II) phase phospholipid correctly determined that all cases were LA negative. The results of this study suggest that when conducting LA tests on patients undergoing DOAC therapy, it is important to perform a confirmation test using Staclot LA reagent.

The peripheral airways (inner diameter less than 2.0 mm), particularly the bronchioles, are important in the pathogenesis of chronic respiratory diseases, such as chronic obstructive pulmonary disease (COPD). Since the pathological lesions in the peripheral airways are associated with airflow obstruction in COPD, early detection of these lesions is important. However, current pulmonary function tests only assess the function of entire lungs, making it difficult to detect precise lesions in the peripheral airways and to identify their location. We have developed and improved a miniaturized thermal flow sensor, which enables the assessment of peripheral airways via bronchoscopy, by using microelectromechanical systems (MEMS) technology. In this study, we measured pulmonary functions in rats, which trachea has a similar diameter to human peripheral airways, using our developed miniaturized thermal flow sensor. Respiratory changes were measured and assessed under normal breathing conditions, following the administration of bronchoconstrictive agents, and in COPD model rats, based on respiration rate, tidal volume, and respiratory time using our sensor. The sensor detected respiration rate and tidal volume under normal breathing conditions. The extension of respiratory time and reduction in tidal volume were detected by the administration of a bronchoconstrictive agent. Furthermore, the extension of expiratory time and the reduction in expiratory volume in COPD model rats were also detected by the sensor. These results suggest that our developed sensor may be a valuable tool for diagnosing and assessing the disease severity, as well as evaluating the drug efficacy, in various diseases, where peripheral airway lesions play a significant role, including COPD.

Appropriate nutritional management requires comprehensive decisions based on multiple nutritional and clinical indicators. In this study, we retrospectively evaluated the usefulness of blood biomarkers as prognostic factors in NST rounds to lead to appropriate nutritional management of undernourished patients. We targeted 176 patients who received NST rounds at our hospital, adjusted for age and gender by propensity score matching. The dependent variable was the outcome at discharge as assessed by the attending physician (favorable group, unfavorable group), and the explanatory variables were blood biomarkers (ALB, ChE, CRP, Hb, RBP, TC, Tf, TLC, TTR, WBC) tested before NST rounds and statistically analyzed. Multivariate logistic regression analysis showed significant differences in Hb, RBP, TLC, WBC, and AUC ranged from [0.650 (95%CI: 0.570–0.731)] to [0.722 (95%CI: 0.647–0.797)] in comparison between before (basal model) and after (enhanced model) adding the four items mentioned above. The IDI value was [0.076 (95%CI: 0.036–0.116), p < 0.001]. In the decision tree analysis, TLC was an important factor in the prognosis of undernourished patients. Combining the tests of immunocompetence and nutritional assessment protein with short half-lives improves prediction accuracy in undernourished patients. We expect future visual prognosis prediction by IDI and decision tree analysis using patient information on detailed nutritional assessment. We found that measured TLC, RBP, Hb, and WBC values before NST rounds were important prognostic factors.

Appropriate evaluation of individual phlebotomy skills is essential for the efficient functioning of a phlebotomy room. In our hospital’s phlebotomy room, we have established an evaluation system for phlebotomy skill levels based on two key indicators: the number of blood draws attempted and rate of phlebotomy handoffs. This system classifies skill levels into four tiers (SS, S, A, and B) and serves as a tool for visualizing staff competency, facilitating the identification of appropriate personnel for phlebotomy handoffs. This study examined the effectiveness and practical application of this evaluation system. The clear classification of skill levels facilitated timely handoff requests and contributed to a more balanced distribution of workload. Staff with higher skill levels achieved higher success rates in blood collection and completed the procedure in less time. Approximately 60% of the staff held a positive view of the system, indicating its general acceptance. However, approximately 10% raised concerns, indicating the necessity for administrators to effectively manage the system while fostering staff engagement and consensus for its appropriate implementation. This study demonstrated that the phlebotomy skill level evaluation system serves as an objective and quantitative indicator of phlebotomy proficiency. The system is anticipated to aid staff in setting professional goals and engaging in continuous training, thus improving the overall skill level within the phlebotomy room. Furthermore, reducing the number of venipuncture attempts and preventing phlebotomy-related complications may contribute to patient safety improvement.

Autotaxin (ATX) levels increase in the blood during liver fibrosis and can identify fibrosis earlier than conventional liver fibrosis markers. In this study, we conducted a basic performance and clinical performance evaluation of “ATX Autowako,” released by Fujifilm Wako Pure Chemical Corporation. The measurement instrument used was the LABOSPECT 008 α (Hitachi High-Tech). Basic investigations included reproducibility, linearity, quantitation limit, influence of coexisting substances, correlation (plasma and control instruments/reagents: FEIA method), and sample storage stability. Additionally, as part of the clinical performance evaluation, we examined differences in ATX activity values according to sex and age groups. A total of 240 subjects (120 males and 120 females) with normal liver function were included, excluding patients with rheumatoid arthritis and cancer. The results of basic performance evaluation were satisfactory. In the clinical performance evaluation, consistent with previous reports, ATX levels were higher in females than in males, with no age-related differences. The evaluated reagent is suitable for use with a general automatic biochemistry analyzer, making it cost-effective for introduction and we believe it is useful as a reagent that can be assessed similarly to existing ones.

[Introduction] IMMUCOR NEO Iris (Iris) is a device based on the direct agglutination method and the solid phase method (Capture method) that specifically detects IgG antibodies. The equivalency and reproducibility of anti-A/B antibody titration were evaluated using Iris. [Method] The dilution accuracy was evaluated by using Orange G as a sample by measuring the absorbance of the dilution series performed during the IgM antibody titration assay. Repeatability and Between-day precision was evaluated by analyzing 10 and 5 times respectively. The correlation was compared with the test tube method using of the 64 patient samples. The test tube method was performed by saline method for IgM antibody titration, and the IAT method for IgG antibody titers. [Results] The dilution accuracy of Iris was evaluated up to 128 titer, and the margin of error was less than one titer. The margin of error was within two titers for both repeatability and Between-run reproducibility. The concordance rate within one titer was 100% for IgM antibody titration, for IgG titration, was 89% without DTT treatment and 98% with DTT treatment. However, in the correlation evaluation of IgG antibodies, discrepancies were observed in one specific patient. With the Capture method, The difference between DTT-untreated samples and DTT-treated samples with the Capture method was mostly within one titer. [Conclusion] Iris can adequately perform serial dilution automatically and is highly correlated with the test tube method, making it useful for measuring antibody titers. IgG antibody titration using Capture method has high specificity for IgG antibodies and does not necessarily require DTT treatment.

Vancomycin-resistant enterococci (VRE) are drug-resistant bacteria critical for infection control in clinical settings. This study evaluated the performance of the ChromoAgar^TM VRE blue plate (CH-blue), a novel rapid VRE screening tool, compared to the BD BBL^TM VRE selective plate (BD-VRE). The evaluation included enterococcal strains carrying vanA and vanB genes (7 strains), plasmid resistance gene-free strains (11 strains), and clinical stool samples (98 samples). The study also investigated CH-blue’s inhibitory capacity over time post-manufacture, using seven plasmid resistance gene-free strains capable of growing on CH-blue. CH-blue showed robust growth and superior visibility for vanA and vanB strains with VCM concentrations ≥ 16 μg/mL after 24 hours compared to BD-VRE. The stealthy vanB-type VRE with VCM ≤ 8 μg/mL was detected at lower bacterial concentrations on BD-VRE, while CH-blue required higher concentrations. Prolonged incubation of CH-blue beyond 48 hours reduced its inhibitory performance against some plasmid resistance gene-free strains, which further declined as its expiration date approached. These findings indicate that CH-blue is effective for rapid VRE detection within 24 hours but less sensitivity for stealthy vanB-type VRE. The selectivity of CH-blue for plasmid resistance gene-free strains decreased with prolonged incubation and approaching expiration date. BD-VRE offers higher sensitivity and selectivity in these cases. Therefore, selecting the appropriate plate requires understanding their characteristics and considering evaluation timelines and facility conditions.

C-peptide reflects insulin secretion capacity from pancreatic β-cells and is used to evaluate endogenous insulin secretion in diabetic patients, particularly for tracking temporal changes in secretion capacity or assessing insulin dependency. In this study, we evaluated the performance of the “HISCL C-Peptide Reagent” (Sysmex Corporation) for C-peptide measurement using the fully automated immunoassay analyzer HISCL-5000 (Sysmex Corporation), based on chemiluminescent enzyme immunoassay principles. The evaluation focused on reproducibility, analytical range, specificity, comparison between serum and sodium fluoride-added plasma samples, and correlation with a reference method. The results demonstrated satisfactory reproducibility, analytical range, and correlation with the reference method. However, specificity was negatively impacted in the presence of high concentrations of biotin. Comparison between serum and sodium fluoride-added plasma samples showed good correlation, although slight variability was observed in higher concentration ranges. Similarly, while the correlation with the reference method was strong, a negative slope was noted. These findings suggest that the HISCL C-Peptide Reagent possesses sufficient performance for routine measurement of serum C-peptide levels. Nonetheless, discrepancies among reagents in higher concentration ranges necessitate careful temporal management when transitioning between different reagents.

Comprehensive genomic profiling method typically uses tissue samples to analyze cancer-related genes via next-generation sequencing. Liquid biopsy using blood cell-free DNA (cfDNA) has recently gained attention. However, standardization of procedures from blood collection to analysis remains challenging, particularly due to the unknown effects of collection tube type and storage conditions on cfDNA quality. In this study, blood samples were collected from 10 healthy individuals in three types of tubes: ethylenediaminetetraacetic acid (EDTA)-2Na, EDTA-2K, and cfDNA tubes. cfDNA was extracted from the plasma, and total DNA concentration was measured via fluorescence assay. All samples were stored at –80°C and analyzed at different time points (within 7 days and 1, 3, and 6 months), and cfDNA band patterns were examined. Notably, no significant differences in total DNA yield were observed among all tube types. Moreover, cfDNA band patterns were consistent across all tube types and storage durations. Therefore, both EDTA tubes can replace cfDNA tubes for cfDNA extraction. Furthermore, cfDNA quality was maintained for up to 6 months under –80°C storage conditions. Overall, this study provides critical insights for the standardization of cfDNA analysis in liquid biopsy, facilitating the design of more reliable and reproducible workflows in clinical and research settings.

Growth hormone (GH) and insulin-like growth factor 1 (IGF-1) are critical biomarkers for diagnosis and assessing therapeutic efficacy in conditions such as GH hypersecretion, including acromegaly, and GH deficiency. This study evaluated the basic performance of GH and IGF-1 reagents for the automated chemiluminescence immunoassay analyzer (AIA^®-CL1200), developed by Tosoh Corporation, with a focus on their interactions with therapeutic agents for GH secretion disorders. The findings demonstrated high accuracy, specificity, quantification limits, and linearity. Both GH and IGF-1 measurements showed a strong correlation with the control method, except for a single case where a discrepancy was identified in IGF-1 results. Interference testing with therapeutic drugs for GH secretion disorders, including the GH receptor antagonist pegvisomant, revealed that the control method exhibited falsely elevated GH levels due to direct interaction by pegvisomant. In contrast, the AIA-CL system avoided this interaction. No drug-related interference was observed in either the AIA-CL or control method for other tested medications. In conclusion, the GH and IGF-1 reagents for the AIA-CL demonstrated good basic performance, and in particular, the GH reagent was excellent in that it showed no cross-reactivity with pegvisomant. Additionally, the simultaneous measurement of GH and IGF-1 using the AIA-CL system enables pre-examination testing, which is anticipated to lead to timely and appropriate treatment.

Improving work efficiency in the emergency room (ER) not only benefits patients, but also reduces the work burden on doctors and nurses. Electrocardiogram testing procedures in ERs are complicated and cannot support real-time image transmission. This time, we have constructed a system for safe and real-time image transmission using Wi-Fi in the ER, and will report on its effectiveness. According to the current analysis, (1) there are seven work processes from inputting the inspection request to image transmission, which is complicated. (2) ID entries may be made incorrectly or records may be recorded without ID entry, leading to incidents. Additionally, it has become clear that it takes time to confirm the recorded electrocardiograms. By using Wi-Fi, (1) seven work processes were reduced to four. (2) By using a barcode reader, patient attributes are acquired, which prevents misidentification of patients. Additionally, if attributes were not obtained, it would be possible to detect omissions in inspection request input, which helped prevent accounting omissions. (3) Since images can be transmitted in real time, it is now possible to provide prompt medical treatment. (4) The processing time required for image transmission work was reduced by up to 70%. Operation using Wi-Fi not only improved operational efficiency in the ER, but also enabled safe and speedy medical treatment by reliably acquiring patient information and transmitting electrocardiogram images in real time. Additionally, the time required for post-recording electrocardiogram processing and transmission work has been significantly reduced, leading to improved work efficiency.

The supply restriction of blood culture bottles (Bactec) that occurred in July 2024 had a significant impact on the testing system in Japan. In our center, in order to maintain the current two-set collection rate during the restriction period, Bactec was used for the first set and Signal was used as a substitute for the second set (439 cases). The positive rate was 16.2%, of which 45.1% were positive for both sets, 42.3% were positive for only the first set, and 12.7% were positive for only the second set. The detected bacterial species were almost the same for both sets, but the time it took to become positive was slower for the second set, with 46.7% being delayed by more than half a day. In all cases with positive blood cultures, the infection control team intervened, and looking at whether or not antibiotics were changed in the 64 cases excluding contamination and death, the antibiotics used were appropriately changed in 13 of the 33 cases with 1 positive set (39.4%). In contrast, in the case of 2 positive sets, the rate was significantly higher at 23 of the 31 cases (74.2%) (p = 0.032), indicating that the number of positive sets has a large impact on the decision to change antibiotics. and antibiotic adsorption functions, we believe that it has played a role as an alternative. We must not allow any interruption in medical treatment or inconvenience to patients. We hope that this emergency will serve as an opportunity to consider how laboratories can operate without compromising on quality.

Digital image analysis was conducted to examine in detail the morphological changes in red blood cells during the initial stage of heating, following brief exposure to a contact temperature of 50°C. The shape, size, and frequency of the occurrence of the cells was calculated, and they were classified by shape and size. Human heparinized peripheral blood from six subjects was used. Two volumes of whole blood, (250 μL and 500 μL) were heated in a constant temperature bath, followed by smear preparation and May-Giemsa staining to assess the morphology of emerging poikilocytes. A significant increase in poikilocytes was observed following heating in both the 250 μL and 500 μL samples. Following heating times of 60, 90, and 120 seconds, category 4 poikilocytes appeared most frequently in both volumes. Our findings suggest that by categorizing cells based on morphology and size, we can determine the occurrence rate and overall distribution of poikilocytes in peripheral blood.

Internal quality control (IQC) in clinical laboratory testing is indispensable for ensuring the reliability of test results. However, there are no clear regulations on specific implementation methods or the samples used, and each facility operates independently. ISO 15189:2022 recommends the use of third-party serum-based samples. In this study, we evaluated the efficiency of IQC operations by switching from conventional lyophilized samples—which require dissolution, aliquoting, and frozen storage-to tube-type liquid frozen samples. We compared the intra-laboratory reproducibility (CV%) over 20 days between old and new samples for test items measured using GA09IIα, HLC-723G11, and cobas 8000. The results showed no significant difference in precision for any of the items. Additionally, the ability to reseal and refrigerate the new samples eliminated the need for aliquoting, freezing, thawing, and mixing, significantly reducing the preparation time before measurement from the conventional approximately 6 hours per week. The consumable cost per measurement also decreased from 46 yen to 20 yen. Challenges remained, such as sample barcodes not being compatible with the testing system—necessitating label replacement and external retrieval of reference ranges—but the new samples facilitated easier comparison with reported values worldwide and were useful as a substitute for external quality assessments. In conclusion, the utilization of tube-type liquid frozen IQC samples was suggested to be useful for operational efficiency and precision improvement.

The patient was a male in his 60s. He was on hemodialysis for end-stage renal failure due to IgA nephropathy and had a history of chronic hepatitis C and hypertension. Two years after undergoing aortic valve replacement (AVR) with a bioprosthetic valve (CEP Magna EASE 23 mm) for severe aortic regurgitation due to the presence of right coronary cusp prolapse, he developed chest discomfort on exertion and hypotension during dialysis. Transthoracic echocardiography (TTE) performed at a routine outpatient clinic showed marked calcification of the biological valve and limited patency, with a significant increase in peak velocity of 5.32 m/sec at the prosthetic valve site. Then, a diagnosis of structural valve deterioration (SVD) was made, and a mechanical valve replacement (ATS AP360 22 mm) was performed. The patient had a good postoperative course and was discharged on postoperative day 21. It has been reported that dialysis patients are prone to cardiovascular calcification and atherosclerosis, resulting in earlier SVD. In the present case, the maximum blood flow velocity at the prosthetic valve site increased to 2.91 m/sec at TTE 1 year postoperatively, confirming severe prosthetic valve stenosis at 2 years postoperatively. Short-term follow-up of TTE after AVR in hemodialysis patients should be considered. In conclusion, frequent follow-up with TTE and monitoring changes in Doppler indices are essential for early diagnosis of SVD after AVR in hemodialysis patients. The findings from this case study will contribute to improving management methods after AVR in dialysis patients.

Nuclear protein in testis (NUT) carcinoma is a rare, aggressive, and poorly differentiated carcinoma hallmarked by NUT gene rearrangement. Here, we report a case of unknown primary NUT carcinoma diagnosed using pleural effusion cytology. A man in his 90s presented with left upper abdominal pain. Chest computed tomography (CT) scans revealed a massive pleural effusion in the left thorax and, consequently, chest drainage was performed. Smears of pleural effusion cytology revealed small to medium-sized, monomorphic, round atypical cells exhibiting a high nuclear-cytoplasmic ratio, round to ovoid nuclei with prominent nucleoli, and scant cytoplasm. The cells appeared singly and in clusters. Cell-block specimens showed atypical cells with the same morphology as those observed in the pleural effusion cytology specimens, and the atypical cells were positive for p63, p40, and NUT, which supported the diagnosis of NUT carcinoma. Following the chest drainage, no primary tumor was identified through CT scans. The patient died 34 days after admission. Because of the poorly differentiated cytomorphology exhibited by NUT carcinoma, its diagnosis in the cytology specimens is very challenging. In the present case, immunohistochemistry of cell-block specimens was essential for a definitive diagnosis of NUT carcinoma by pleural effusion cytology.

Equilibrium function testing is essential for determining the cause of dizziness, particularly in distinguishing between central and peripheral types of nystagmus. Central dizziness can be life-threatening, and there for early detection and treatment are essential. A 59-year-old man suddenly developed vertigo and visited the emergency department of our hospital. The patient presented with unsteadiness, hearing loss, ear fullness, and nystagmus when gazing up, down, left, or right; however, a computed tomography (CT) scan revealed no obvious intracranial lesions. Additionally, a magnetic resonance imaging (MRI) scan ruled out acute cerebral infraction, although a left vertebral artery infarction was noted. Therefore, sudden deafness was suspected, and the patient was monitored. On the fourth night after admission, he developed numbness in the left cheek, followed by left facial nerve paralysis on the next morning. A hearing test conducted on the fifth day of hospitalization indicated worsening hearing loss. Furthermore, the equilibrium function test revealed nystagmus, suggesting a central cause. A repeat MRI scan confirmed a cerebral infarction, leading to a diagnosis of anterior inferior cerebellar artery infarction. When hearing loss or dizziness is present, it is essential to conduct a comprehensive diagnosis based on subsequent cerebellar symptoms and findings from the equilibrium function test, as acute cerebral infarction may not be effectively diagnosed by imaging tests.

We report a case of diffuse large B-cell lymphoma (DLBCL) presenting with antiphospholipid antibodies. An elderly male patient presented to a local clinic with back pain and was found to have multiple bone lesions. PET-CT revealed lymph node enlargement with high FDG uptake, leading to referral to our hospital for further evaluation and treatment. Initial laboratory findings showed prolonged APTT (61.0 sec), elevated IgM (1,239.3 mg/dL), and increased sIL-2R (2,608 U/mL). Immunofixation identified both IgM κ and IgM λ M-proteins. Lymph node biopsy revealed CD5, CD19, and CD20 positive cell populations, confirming the diagnosis of DLBCL. Further investigation of prolonged APTT showed inhibitor patterns in both immediate and delayed mixing tests. Russell’s viper venom time was 1.27, and ELISA detected only IgM anticardiolipin antibodies (aCL). Despite these findings, antiphospholipid syndrome was not diagnosed due to the absence of thrombotic events. Treatment with dexamethasone and local radiation therapy was initiated, followed by rituximab-based chemotherapy. APTT normalized concurrent with declining IgM levels, suggesting that prolonged APTT was caused by β2GPI-independent IgM aCL, based on ELISA methodology. This case highlights the importance of careful interpretation of laboratory results in patients with M-proteins. Moreover, as DLBCL with IgM M-protein reportedly carries a poor prognosis, careful monitoring of disease progression is warranted.

Myelodysplastic/myeloproliferative neoplasm (MDS/MPN) is a category of diseases that combines features of both MDS and MPN. In this report, two cases with the cytogenetic abnormality del(5q), as well as JAK2V617F mutation which is frequently detected in MPN, are described. Case 1 was a woman in her 60s who was referred to our hospital for detailed examination of her polycythemia and thrombocythemia. Peripheral blood examination showed pancythemia, and JAK2V617F mutation was present. The bone marrow showed hyperplasia and an increased number of megakaryocytes with small non-lobated nuclei. Chromosomal analysis showed an isolated del (5q), but it did not meet the criteria for MDS, and a diagnosis of MDS/MPN was made. Case 2 was a man in his 70s who was referred to our hospital for detailed examination of macrocytic anemia and mild thrombocythemia. JAK2V617F mutation was positive, and the bone marrow showed normocellular marrow with pseudo-Pelger Huët anomaly in neutrophils and increased megakaryocytes with small, non-lobated nuclei. Chromosomal analysis showed some karyotypic abnormalities in addition to del(5q), resulting in a diagnosis of MDS. Since both cases showed megakaryocyte morphology characteristic of MDS del(5q), it may be possible to suspect the presence of del(5q). However, when JAK2V617F mutation or chromosomal abnormalities other than del(5q) are present, peripheral blood findings and bone marrow morphology are different from those typical of MDS del(5q), and the diagnosis is not always definite. Appropriate diagnosis by cytogenetic and molecular biological testing in laboratories will become increasingly necessary.

The predominant types of carbapenemase (CP) produced by CP-producing Enterobacterales vary by region. Here, we report a case of pyelonephritis caused by Escherichia coli producing New Delhi metallo-β-lactamase-5 (NDM-5) and having a mutation in penicillin-binding protein 3 (PBP3) in an elderly Japanese who had never traveled abroad. An 84-year-old man residing in a nursing home and having left pyeloureteral junction stenosis was hospitalized because of fever and abdominal pain. Physical examination and computed tomography scanning showed findings consistent to left obstructive pyelonephritis. A ureteral stent was placed and administration of ceftriaxone started empirically, which improved the patient’s symptoms on the next day. The administered antibiotic was switched to intravenous fosfomycin on day 4 because CP-producing E. coli was detected in the blood and the urine collected from the patient on admission, which was given until day 18. The isolated strains, whose sequence type was ST410, had the bla_NDM-5 gene located on an IncX3-type plasmid and a mutation of p.P333_Y334insYRIN in PBP3. Because epidemiological data of E. coli ST410 and that with PBP3 mutations have been limited in Japan, further studies are needed to characterize these groups of E. coli in this country.

Candida allociferrii is a rare yeast-like fungus that has been proposed to be one of the species within the Stephanoascus ciferrii complex. In Japan, only one case of isolation from an orbital abscess has been previously reported. We herein report a case of otomycosis caused by C. allociferrii. The patient was a male in his 50s who presented with pruritus and otorrhea in the right ear. A sample of ear discharge was submitted for examination. On the first day of culture, small colonies were observed on the medium, thus prompting Gram staining and extended incubation. In the Gram staining of the colonies, yeast-like fungi with spores arranged in parallel on one side of the hyphae were observed. By the fifth day of culture, the colonies exhibited wrinkles and appeared to be embedded in the medium. Such Gram staining and colony morphology suggested the possibility that this fungus represented a major Candida species. However, biochemical characterization and mass spectrometry failed to provide an accurate species identification. Sequencing of the ITS and D1/D2 regions finally identified the isolate as C. allociferrii. These findings indicate that genetic sequencing is useful for the precise identification of this species, and previous reports have suggested that C. allociferrii exhibits resistance to azole antifungals. In the present case, the MIC of fluconazole was elevated. Given that fluconazole is often the first-line treatment for invasive candidiasis, early morphological and culture-based presumptive identification followed by rapid reporting may help to allow medical personnel to perform timely and appropriate treatment.