Nationwide genome surveillance of carbapenem-resistant Pseudomonas aeruginosa in Japan.

Japan is a country with an approximate 10% prevalence rate of carbapenem-resistant Pseudomonas aeruginosa (CRPA). Currently, a comprehensive overview of the genotype and phenotype patterns of CRPA in Japan is lacking. Herein, we conducted genome sequencing and quantitative antimicrobial susceptibility testing for 382 meropenem-resistant CRPA isolates that were collected from 78 hospitals across Japan from 2019 to 2020. CRPA exhibited susceptibility rates of 52.9%, 26.4%, and 88.0% against piperacillin-tazobactam, ciprofloxacin, and amikacin, respectively, whereas 27.7% of CRPA isolates was classified as difficult-to-treat resistance P. aeruginosa. Of the 148 sequence types detected, ST274 (9.7%) was predominant, followed by ST235 (7.6%). The proportion of urine isolates in ST235 was higher than that in other STs (P = 0.0056, χ2 test). Only 4.1% of CRPA isolates carried the carbapenemase genes: blaGES (2) and blaIMP (13). One ST235 isolate carried the novel blaIMP variant blaIMP-98 in the chromosome. Regarding chromosomal mutations, 87.1% of CRPA isolates possessed inactivating or other resistance mutations in oprD, and 28.8% showed mutations in the regulatory genes (mexR, nalC, and nalD) for the MexAB-OprM efflux pump. Additionally, 4.7% of CRPA isolates carried a resistance mutation in the PBP3-encoding gene ftsI. The findings from this study and other surveillance studies collectively demonstrate that CRPA exhibits marked genetic diversity and that its multidrug resistance in Japan is less prevailed than in other regions. This study contributes a valuable data set that addresses a gap in genotype/phenotype information regarding CRPA in the Asia-Pacific region, where the epidemiological background markedly differs between regions.

Characteristics of chronic lymphocytic leukemia in Japan: Comprehensive analysis of the CLLRSG-01 study.

Chronic lymphocytic leukemia (CLL) is rare in Japan. We conducted the nationwide, prospective observational study CLLRSG-01 to clarify the current state of CLL in Japan and to make accurate international comparisons by preparing naturally air-dried smears like those used in other countries. Of the 201 untreated patients enrolled and evaluated, 119 were diagnosed with CLL and 82 with non-CLL mature B-cell neoplasms, based on the WHO classification. Of the 119 CLL patients, 90 were classified as typical and 29 as atypical according to FAB classification morphology, with the proportion of atypical CLL consistent with reports from other countries. Immunophenotypic analyses by flow cytometry showed that 55% of Japanese CLL patients had a Matutes score of 4 or higher, which is lower than the rate of about 90% in Europeans. Mutated IGHV was identified in 80% of Japanese CLL patients, which is a higher rate than in Western patients. The most frequent IGHV gene was VH3-30 (15%), followed by VH3-23 (12%) and VH4-34 (10%). VH1-69, the most common gene in Western countries, was identified in only one patient. These results indicate that the pattern of immunophenotypes and IGHV gene usage in Japanese CLL patients differs from that in Western patients.

TAFRO Syndrome: A Disease Requiring Immediate Medical Attention.

TAFRO syndrome was first described in 2010, standing for thrombocytopenia, anasarca, fever, reticulin fibrosis and organomegaly. Because the lymph node histopathology of TAFRO syndrome mimics idiopathic multicentric Castleman disease (iMCD), some researchers consider TAFRO syndrome to be a subtype of iMCD. However, the clinical features of TAFRO syndrome considerably differ from those of iMCD without TAFRO. The clinical features of patients with TAFRO syndrome with or without iMCD-histopathology are similar, and these patients require an accurate diagnosis and urgent treatment. Although a histological diagnosis, including a differential diagnosis, is important, lymph node involvement in patients with TAFRO syndrome is usually modest or sometimes absent. Furthermore, a bleeding tendency due to thrombocytopenia and severe anasarca hampers performing a biopsy. Nonetheless, patients with various other disorders may manifest TAFRO syndrome-like symptoms, making the differential diagnosis in borderline cases difficult. Therefore, the establishment of precise and specific biomarkers is important.

Castleman disease and TAFRO syndrome.

Although Castleman disease was first described in 1956, this disease includes various conditions, including unicentric Castleman disease with hyaline vascular histology, human herpesvirus-8 (HHV-8) related multicentric Castleman disease, idiopathic multicentric Castleman disease, and mimics of Castleman disease associated with other conditions. To date, Castleman disease remains incompletely understood due to its rareness and difficulties in clinical and pathological diagnosis. TAFRO syndrome was reported in Japan in 2010. Because lymph node histology is similar in patients with TAFRO syndrome and Castleman disease, TAFRO syndrome is described as a related disorder of Castleman disease. Clinically, however, these conditions differ markedly. Although elevated interleukin-6 (IL-6) expression is characteristic of Castleman disease, increased expression of IL-6 may occur in patients with other diseases, making elevated IL-6 unsuitable for differential diagnosis. Further understanding of these disorders requires the identification of novel disease-specific biomarkers. This review article therefore outlines the characteristics of Castleman disease and TAFRO syndrome.

Reflection analysis of absorbing film with diffractive structures for incoherent light by rigorous coupled-wave analysis.

Reflectivity is useful for evaluating the extinction coefficient; however, it is highly sensitive to the refractive index structure. In this study, we propose a novel, to the best of our knowledge, method for evaluating the influence of the structure on reflectivity using rigorous coupled-wave analysis (RCWA), and apply it to analyze the reflectivity of the dye rhodamine B. The reflection-absorption spectrum of the film was significantly affected by its surface and internal structure. We found that simulating the reflectivity of a film with an unknown internal structure, using the coherency parameter is convenient. The RCWA facilitated simultaneous treatment of the coherent diffraction by the surface structure and incoherent reflection in the film.

Patient's age and D-dimer levels predict the prognosis in patients with TAFRO syndrome.

OBJECTIVES: To identify prognostic factors for TAFRO syndrome, a rare inflammatory disorder of unknown etiology characterized by thrombocytopenia, anasarca, fever, reticulin myelofibrosis, renal dysfunction, and organomegaly. METHODS: Data of patients with TAFRO syndrome were extracted from a Japanese patient registry. Patients were divided into groups according to the clinical and laboratory parameters at initial presentation. Cut-off values for the laboratory parameters were determined using receiver operating characteristic curve analysis and by clinical relevance. Patient survival was analyzed by the Kaplan-Meier method. Univariable analysis was performed using log-rank tests. Multivariable analyses were performed with the logistic regression model and the Cox proportional hazards model. RESULTS: We extracted the data of 83 patients with TAFRO syndrome from the registry. Univariable analysis identified several potential prognostic factors. Of these factors, age ≥60 years and D-dimer ≥18 µg/dL remained significant predictors of poor overall survival in the multivariable Cox proportional hazards model. Based on these results, we developed a simple prognostic scoring system for TAFRO syndrome (TS-PSS). CONCLUSION: Patients in our cohort were stratified into low, intermediate, and high-risk groups by the TS-PSS. This system should be verified with independent patient cohorts in future studies.

Optimal treatments for TAFRO syndrome: a retrospective surveillance study in Japan.

TAFRO syndrome is a systemic inflammatory disorder of unknown etiology characterized by thrombocytopenia, anasarca, fever, reticulin myelofibrosis, renal dysfunction, and organomegaly. Mortality in patients with this syndrome is high; however, an optimal treatment strategy has not been established. To explore the strategy, we retrospectively analyzed 81 patients with TAFRO syndrome registered in the Multicenter Collaborative Retrospective Study for Establishing the Concept of TAFRO Syndrome in Japan by December 2019. Sixty-eight patients received corticosteroid therapy as the first-line treatment, and as the second-line treatment, 21 received tocilizumab (Toc), 14 received cyclosporine A (CsA), and 8 received rituximab (Rit) in addition to corticosteroids. We compared these second-line treatment groups by setting the primary endpoint as time to next treatment or death (TTNT). Kaplan-Meier analysis showed that the median TTNT in the Toc, CsA, and Rit groups were 2.8 months, 9.2 months, and not reached, respectively. The TTNT of the Rit group was significantly longer than that of the Toc group. In contrast, there were no significant differences in overall survival between groups, indicating that subsequent salvage therapies rescued a large proportion of patients who failed the second-line treatments. Further studies are warranted to establish the optimal treatment strategies for this syndrome.

Measurable residual disease in the treatment of chronic lymphocytic leukemia.

Treatment outcomes of chronic lymphocytic leukemia (CLL) have improved since chemoimmunotherapy and novel drugs became available for CLL treatment; therefore, more sensitive methods to evaluate residual CLL cells in patients are required. Measurable residual disease (MRD) has been assessed in several clinical trials on CLL using flow cytometry, real-time quantitative PCR (RQ-PCR) with allele-specific oligonucleotide (ASO) primers, and high-throughput sequencing. MRD assessment is useful to predict the treatment outcomes in the context of chemotherapy and treatment with novel drugs such as venetoclax. In this review, we discuss major techniques for MRD assessment, data from relevant clinical trials, and the future of MRD assessment in CLL treatment.

High accuracy cross-sectional shape analysis by coherent soft x-ray diffraction.

When the scatterer size is less than 100 wavelengths, the effect of diffraction is large. The analysis of diffraction is important for 3D shape measurement. However, in soft x rays, shapes suitable for rigorous diffraction analysis have been limited to ellipses and periodic structures. We have developed a method to expand this to any shape (isolated triangle, rectangle, etc.). Experimentally, we measured the respective widths of the cross section of a column consisting of two layers and showed that the resolution was at least a few wavelengths. For this purpose, we have also developed a fast simulation method with a small memory size.

Epidemiological analysis of multicentric and unicentric Castleman disease and TAFRO syndrome in Japan.

Castleman disease is a polyclonal lymphoproliferative disease which is clinically classified into unicentric (UCD) and multicentric (MCD). TAFRO syndrome is a relatively new concept that partly overlaps with MCD. Due to their rarity, their incidence remains unknown. This study investigated the incidence and prevalence of UCD, MCD, and TAFRO syndrome in Japan using a fixed-point observation method based on their incidence in Ishikawa prefecture. The annual incidences of MCD, UCD, and TAFRO syndrome in Japan were 309-731, 71-542, and 110-502, respectively, yielding annual incidence rates per million individuals of 2.4-5.8, 0.6-4.3, and 0.9-4.9, respectively, and nationwide prevalence of 4,180-14,900, 1,350-10,300, and 860-7,240, respectively. In conclusion, MCD, UCD and TAFRO syndrome may not be as rare as previously estimated in Japan.

The potential role of follicular helper T cells in idiopathic multicentric Castleman disease with and without TAFRO syndrome.

Idiopathic multicentric Castleman disease (iMCD) is a systemic inflammatory disease of unknown etiology caused by hypercytokinemia. Recently, TAFRO (thrombocytopenia, anasarca, fever, renal failure or reticulin fibrosis, and organomegaly) syndrome has been reported, which shows similar histopathological findings to iMCD and factors associated with a poor prognosis. iMCD shows no plasma cell infiltration in the germinal center (GC), but CD38-positive (CD38+)-plasma cells are observed in the interfollicular area. Our previous report revealed that atrophic change of GC, glomeruloid vascular proliferation, and abnormal proliferation of follicular dendritic cells are more prominent in iMCD with TAFRO (TAFRO+) in comparison to iMCD without TAFRO (TAFRO-). In addition, the numbers of CD38+ and immunoglobulin G4-positive (IgG4+) plasma cells were decreased in the interfollicular area. The roles of T follicular helper cells (Tfh) are well-known to assist B-cell proliferation, maturation, and differentiation．It maintains the formation of GC and is also related in the class switching of IgG isotypes, including IgG4. Thus, we immunohistochemically examined the number of Tfh in GCs in both TAFRO- and TAFRO+ iMCD. The number of Tfh was significantly decreased in TAFRO- iMCD (n = 9) and was further decreased in TAFRO+ iMCD (n = 18) in comparison to non-specific lymphadenopathy (n = 6) and IgG4-related disease (n = 4). These results suggest that decreased Tfh may be one etiology of iMCD.

Is TAFRO syndrome a subtype of idiopathic multicentric Castleman disease?

Castleman disease (CD) is a rare lymphoproliferative disorder that can be unicentric or multicentric. Multicentric CD (MCD) is further subdivided into human herpesvirus type-8-associated, POEMS syndrome-associated, and idiopathic (iMCD). TAFRO syndrome is a newly identified disorder of unknown etiology characterized by thrombocytopenia, anasarca, fever, reticulin myelofibrosis, renal dysfunction, and organomegaly. The TAFRO syndrome is sometimes regarded as a subtype of iMCD (TAFRO-iMCD), whereas iMCD without TAFRO syndrome is considered "not otherwise specified" (iMCD-NOS). However, a proportion of patients with TAFRO syndrome have been diagnosed without lymph node biopsies (TAFRO syndrome without proven iMCD; TAFRO-w/op-iMCD). To clarify the clinical features of iMCD-NOS, TAFRO-iMCD, and TAFRO-w/op-iMCD, we retrospectively analyzed 220 patients extracted from the database of the Multicenter Collaborative Retrospective Study for Establishing the Concept of TAFRO Syndrome. The patients included 87 with iMCD-NOS, 63 with TAFRO-iMCD, and 19 with TAFRO-w/op-iMCD. Patients in all three groups exhibited anemia, hypoalbuminemia, and elevated serum C-reactive protein and interleukin-6 levels. No significant differences in clinical, laboratory, and prognostic features were noted between the TAFRO-iMCD, and TAFRO-w/op-iMCD groups. However, the iMCD-NOS group exhibited polyclonal hyper-γ-globulinemia. The five-year survival rates of patients in the iMCD-NOS and TAFRO-involved groups were 100% and 66.5%, respectively (dropping markedly during the first few months in the latter). The iMCD-NOS and the TAFRO-iMCD samples typically showed plasma cell and mixed-type histologies, respectively. Thus, iMCD can be classified into two distinct subtypes, iMCD-NOS and TAFRO-iMCD. As such, TAFRO-iMCD and TAFRO-w/op-iMCD may be considered the same entity, requiring prompt diagnosis and intensive care.

An extranodal histopathological analysis of idiopathic multicentric Castleman disease with and without TAFRO syndrome.

Thrombocytopenia, anasarca, fever, renal failure or reticulin fibrosis, and organomegaly (TAFRO) syndrome, a poor prognostic clinical condition showing similar histopathological findings to idiopathic multicentric Castleman disease (iMCD), has been reported in Japan. In our previous report, a clinicopathological analysis was performed on 70 nodal cases of iMCD with/without TAFRO. iMCD is classified into three types based on histopathology: (i) plasmacytic (PC), (ii) mixed, and (iii) hypervascular (hyperV). In this report, extranodal histopathological changes of iMCD with/without TAFRO were analyzed. Regarding the kidney pathology, we observed the proliferation of mesangial cells with positive staining of interleukin-6 (IL-6), consistent with membranoproliferative glomerulonephritis, in two cases of iMCD with TAFRO. The number of megakaryocytes per high-powered fields was not significantly different between iMCD cases with and without TAFRO. In conclusion, extranodal lesions of iMCD with/without TAFRO showed various interesting histopathological findings. These lesions may therefore be related to the clinical condition of TAFRO. Obtaining further knowledge about TAFRO will require the observation of nodal as well as extranodal lesions.

A case of chronic lymphocytic leukemia complicated by autoimmune hemolytic anemia due to ibrutinib treatment.

Ibrutinib (IBR) covalently binds to the active site of Bruton's tyrosine kinase (BTK) and is used for the treatment of relapsed/refractory chronic lymphocytic leukemia (CLL). Approximately 5-10% of CLL is complicated by autoimmune cytopenia (AIC), such as autoimmune hemolytic anemia (AIHA). Several cases of AIC have reportedly demonstrated improvement during IBR treatment. However, in our case, the patient developed AIHA during oral IBR treatment. As AIHA is exacerbated by the increased number of CLL cells in the peripheral blood, it may have developed because of disease progression rather than IBR use. This phenomenon may also be attributed to the production of autoantibodies due to increased number of CD5+ B cells. In this case, withdrawal of IBR and administration of rituximab improved hemolysis. If AIHA develops during treatment, its etiology must be examined to confirm the effects of treatment.

Identification of the BRAF V600E mutation in Japanese patients with hairy cell leukemia and related diseases using a quenching probe method.

Hairy cell leukemia (HCL) is a rare B-cell lymphoid malignancy that is difficult to distinguish from other morphological variants. The frequency of HCL has not been determined accurately in Japan. Recent studies revealed that the BRAF V600E mutation is the causal genetic event in HCL. We assessed the BRAF mutation in Japanese patients with HCL and related diseases using the quenching probe (QP) method, a single-nucleotide polymorphism detection system, and evaluated the incidence rate of HCL among Japanese patients with chronic lymphocytic leukemia, and related diseases. We identified 18 cases (33.3%) harboring the BRAF mutation among 54 patients diagnosed with, or suspected of having HCL. Of BRAF V600E-positive patients, 7 were only detected using the QP method, not by direct sequencing, whereas 11 were positive using both tests. In a larger cohort of Japanese patients diagnosed with chronic lymphoid leukemia or related diseases, the frequency of HCL was 4%. Patients with the BRAF V600E mutation had a significantly higher frequency of neutropenia, thrombocytopenia, and elevated soluble interleukin-2 receptor and common B-cell surface markers than patients without the mutation. Our results confirm that BRAF V600E-positive HCL is a relatively rare disorder in the Japanese leukemia patient population.

The clinicopathological comparison among nodal cases of idiopathic multicentric Castleman disease with and without TAFRO syndrome.

Multicentric Castleman disease (MCD) is a systemic inflammatory disease potentially caused by an increase in the serum interleukin-6 (IL-6) level. Idiopathic MCD (iMCD) is histopathologically classified into three types: plasmacytic (PC), mixed, and hypervascular (hyperV) types. Recently, a unique clinical phenotype with a poor prognosis overlap with iMCD, thrombocytopenia, anasarca, fever, renal failure or reticulin fibrosis, and organomegaly (TAFRO syndrome), has been reported from Japan, but its detailed clinicopathological features remain unclear. In this study, we performed a clinicopathological analysis of 70 nodal cases of iMCD with and without TAFRO syndrome (n = 37 versus n = 33). Compared with iMCD without TAFRO, iMCD with TAFRO showed more atrophic lymphoid follicles (LF), greater distances between follicles, increased glomeruloid vascular proliferation within the germinal center, and increased follicular dendritic cells. In addition, the hyperV type in particular demonstrated severe atrophic LF and interfollicular vascular proliferation. Among the mixed-type cases, the serum IL-6 levels in iMCD with TAFRO were significantly higher than those in iMCD without TAFRO. Furthermore, compared to iMCD without TAFRO, the numbers of immunoglobulin G4 (IgG4)-positive and CD38-positive plasma cells were significantly decreased in iMCD with TAFRO.

Cross-sectional particle measurement in the resonance domain on the substrate through scatterometry.

We developed a versatile method for three-dimensional shape measurement where a specific particle can be selected on the substrate and its cross-sectional shape and size can be measured. A non-contact fast measurement is possible for the particle in the resonance domain. We applied rigorous coupled-wave analysis to the particle and calculated the diffraction patterns, comparing the patterns with the experimental results to obtain the size and shape. The shape and position of the focusing spot on the scattering particle was controlled precisely. With this method, the category of the analyzable object is extended to more shapes, such as rectangles and triangles, in addition to a conventional ellipsoid.