Peripherally inserted central venous catheters decrease central line-associated bloodstream infections and change microbiological epidemiology in adult hematology unit: a propensity score-adjusted analysis.

Peripherally inserted central venous catheters (PICCs) have a potential advantage in preventing central line-associated bloodstream infection (CLABSI) compared with the centrally inserted ones (CICCs). However, due to a limited number of studies with insufficient statistical evaluation, the superiority of PICCs is difficult to be generalized in adult hematology unit. We conducted a single-center retrospective study and compared the risk of CLABSI between 472 CICCs and 557 PICCs inserted in adult patients with hematological disorders through conventional multivariate models and a propensity score-adjusted analysis. The overall CLABSI incidence in CICCs and PICCs was 5.11 and 3.29 per 1000 catheter days (P = 0.024). The multivariate Cox regression analysis (hazard ratio [HR]: 0.48; 95% confidence interval [CI]: 0.31-0.75; P = 0.001) and Fine-Gray subdistribution analysis (HR: 0.59; 95% CI: 0.37-0.93; P = 0.023) demonstrated that PICC was independently associated with a reduced risk of CLABSI. Moreover, the stabilized inverse probability of treatment weighting analysis, which further reduced the selection bias between CICCs and PICCs, showed that PICCs significantly prevented CLABSI (HR: 0.58; 95% CI: 0.35-0.94; P = 0.029). Microbiologically, PICCs showed a significant decrease in gram-positive cocci (P = 0.001) and an increase in gram-positive bacilli (P = 0.002) because of a remarkable reduction in Staphylococci and increase in Corynebacterium species responsible for CLABSI. Our study confirmed that PICC was a superior alternative to CICC in preventing CLABSI in the adult hematology unit, while it posed a microbiological shift in local epidemiology.

Clinicopathological analysis of diffuse large B-cell lymphoma lacking surface immunoglobulin light chain restriction on flow cytometry.

Although diffuse large B-cell lymphoma (DLBCL) occasionally lacks surface immunoglobulin light chain restriction (iLCR) on flow cytometry (FCM), little evidence is available for iLCR-negative DLBCL. We retrospectively compared clinicopathological features of iLCR-positive and iLCR-negative DLBCL diagnosed at our institute between April 2007 and March 2018. iLCR-positive was defined as a κ/λ ratio less than 0.5 or greater than 3 in the gated population on dual-color FCM, and iLCR-negative as other values. Of 81 DLBCL cases with available immunophenotyping by FCM, 63 iLCR-positive DLBCL (78%) and 18 iLCR-negative DLBCL (22%) cases were identified. Survival outcomes of patients with iLCR-negative DLBCL were comparable with those of patients with iLCR-positive DLBCL. Pathological analysis revealed no significant difference except for the lower expression of BCL6 in iLCR-negative DLBCL (12.5% vs 65.5%, p < 0.001), although there was a slightly higher frequency of necrosis (47.1% vs 20.7%, p = 0.058) and lower expression of CD10 (11.8% vs 35.0%, p = 0.078) in iLCR-negative DLBCL than in iLCR-positive DLBCL. The underlying mechanism remains unclear; however, low expression of germinal center markers and tumor necrosis may be associated with the loss of iLCR in DLBCL.

Importance of diagnosis-to-treatment interval in newly diagnosed patients with diffuse large B-cell lymphoma.

Treatment of patients with malignancy sometimes be delayed due to various reasons. Several studies revealed that an influence of diagnosis-to-treatment interval (DTI) on outcomes differs depending on the type of malignancy. In this study, we evaluated the influence of DTI on clinical outcomes in newly diagnosed patients with diffuse large B-cell lymphoma (DLBCL). A total of 199 patients were identified with a median DTI of 22 days. At 2 years, patients with short DTI (0-22 days) showed significantly poorer OS (62.7% vs 86.4%) and PFS (55.1% vs 75.9%) compared to those with long DTI (over 22 days). Although short DTI was strongly correlated with several known adverse factors, it remained to be an independent prognostic factor by multivariate analysis. In conclusion, our study confirmed the importance of DTI in patients with DLBCL. Researchers should consider DTI as one of the important prognostic factors and plan clinical trials to be able to enroll patients with aggressive disease requiring urgent treatment.

Diagnosis of a difficult to differentiate case of early-onset hyperviscosity syndrome caused by IgM type multiple myeloma: a case report.

Hyperviscosity syndrome (HVS) can cause multiple organ damage if not treated immediately. IgM multiple myeloma (IgM MM) is a very rare form of myeloma with clinical features such as elevated serum IgM, and anemia, that resemble Waldenström macroglobulinemia (WM). Distinguishing between these two diseases is important, but can be a challenging problem. It is well known that MyD88 mutations and t(11;14) translocations are useful for differential diagnosis. We diagnosed HVS in a 29-year-old male with IgM MM. He was treated with triplet therapy, autologous hematopoietic stem cell transplantation, and carfilzomib consolidation therapy. His clinical course was monitored by serum IgM levels, and bone marrow myeloma cell counts by multiparameter flow cytometry analysis. After this series of treatments, his HSV disappeared and he reached stringent complete response. In cases of early onset of HVS, IgM MM should be considered in addition to WM.

Human herpesvirus 8-positive multicentric Castleman disease with germinotropic plasmablastic aggregates: Overlapping spectrum of human herpesvirus 8-associated lymphoproliferative disorder.

The diagnosis of human herpesvirus 8 (HHV8)-associated lymphoproliferative disorder (LPD) is challenging because of the rarity and extended spectrum of each entity. A 43-year-old, human immunodeficiency virus seropositive, Japanese man was referred to our department because of persistent fever, generalized lymphadenopathy, jaundice and anasarca. Biopsy of a left axially lymph node demonstrated relatively preserved nodal structure with multicentric Castleman disease (MCD) features. In the germinal center, there were aggregates of HHV8-infected plasmablasts that were diffusely positive for CD38, MUM1/IRF4, LCA, IgM and λ; partially positive for CD30, c-MYC, p53; and negative for CD138, CD20, PAX-5, κ, CD2, CD3 and CD5. A small number of Epstein-Barr virus encoded small RNA (EBER)-positive large cells infiltrated in the outer part of the germinal center and the mantle layer, but the cells copositive for EBER and HHV8 were not evident. We diagnosed the patient as HHV8-positive MCD with germinotropic plasmablastic aggregates, which demonstrated intermediate pathologic features between HHV8-positive MCD and germinotropic lymphoproliferative disorder. The pathogenesis of each HHV8-associated LPD differs in cellular origin, host immune status, cytoplasmic immunoglobulin expression, clonality pattern and EBV infection; however, these factors sometimes overlap and induce extended clinical and pathologic presentations.