Utilizing red blood cell distribution width (RDW) as a reliable biomarker to predict treatment effects after chimeric antigen receptor T cell therapy

Chimeric antigen receptor T cell (CAR-T) therapy is an effective treatment for B cell malignancies. A certain fraction of patients, however, experience post-CAR-T relapse, and due to the difficulty of precise relapse prediction, biomarkers that can predict the strength and duration of CAR-T efficacy are needed before CAR-T infusion. Therefore, we performed a single-center cohort study including 91 diffuse large B cell lymphoma (DLBCL) patients treated with CAR-T in order to identify such a new prognostic biomarker. After confirming that each of the already reported prognostic parameters (disease status at leukapheresis, primary refractoriness, number of treatment lines, CD3+ cell counts at leukapheresis) has only limited predictive performance, we established a new composite parameter by integrating these four variables, and found that it predicts progression-free survival (PFS) after CAR-T infusion with statistical significance. Moreover, after comprehensive correlation analyses of this new composite parameter with all individual laboratory variables, we determined that the standard deviation of red blood cell distribution width (RDW-SD) at leukapheresis shows significant correlation with the composite parameter and may be a prognostic biomarker (R2 = 0.76, p = 0.02). Validation analysis indicated that a higher RDW-SD is significantly associated with poorer PFS after CAR-T cell therapy (HR, 3.46, P = 0.03). Thus, this study suggests that a single parameter, RDW-SD at leukapheresis, is a novel, useful biomarker that can be obtained early to predict therapeutic effects of CAR-T cell therapy. Post-CAR-T maintenance or re-induction therapies should be adopted for higher risk patients, who may relapse after CAR-T therapy.

Population Pharmacokinetic Modeling of Posaconazole in Japanese Patients Receiving Fungal Prophylaxis

BACKGROUND

Posaconazole is a vital drug to treat and prevent invasive fungal infections. Several factors, such as sex, body weight, total serum proteins, dietary intake, and severe mucositis, affect posaconazole pharmacokinetics (PKs). However, the relevance of other factors that affect the PKs of posaconazole in hematopoietic stem cell transplantation (HSCT) is unknown. This study explored factors influencing the PKs of posaconazole in HSCT recipients and nontransplant patients with hematological diseases.

METHODS

The authors conducted a single-institution, retrospective study. Forty-two Japanese inpatients receiving oral posaconazole tablets as prophylaxis for fungal infections were enrolled in this study. A one-compartment model with first-order absorption was used as the structural pharmacokinetic model. A population PK (PopPK) analysis was performed using a nonlinear mixed-effects modeling program, using a first-order conditional estimation method with interactions. Perl-speaks-NONMEM and R were used to evaluate the goodness of fit and visualize the output.

RESULTS

In 29% of the enrolled patients, the serum concentration of posaconazole was <0.5 mcg/mL, considered the effective range. PopPK analysis revealed that the patient had undergone HSCT within 1 year, diarrhea occurred more than 5 times a day, and aspartate aminotransferase were covariates that influenced apparent clearance (CL/F). The CL/F of posaconazole was 1.43-fold higher after HSCT and 1.26-fold higher during diarrhea.

CONCLUSIONS

PopPK analysis revealed that HSCT, diarrhea, and aspartate aminotransferase were factors associated with the CL/F of posaconazole. The trough concentration of posaconazole may be below the therapeutic range in a few patients with diarrhea and/or after HSCT. As invasive fungal infections in patients with hematologic diseases can be life-threatening, therapeutic drug monitoring of posaconazole is strongly recommended, and patients should be carefully monitored.

Clinical Impact of Cytokine Release Syndrome on Prolonged Hematotoxicity after Chimeric Antigen Receptor T Cell Therapy: KyoTox A-Score, a Novel Prediction Model

Prolonged hematotoxicity is the most common long-term adverse event in chimeric antigen receptor T cell therapy (CAR-T). To evaluate the impact on prolonged cytopenia of inflammatory status after CAR T infusion, we performed a single-center retrospective study and analyzed patients with B cell lymphomas after CAR-T. Among 90 patients analyzed at 90 days after infusion, the cumulative incidence was 57.5% for prolonged neutropenia, 36.7% for anemia, and 49.8% for thrombocytopenia. Patients who experienced cytokine release syndrome (CRS) had significantly higher incidence and longer duration of prolonged cytopenia. In addition, we found that among patients with grade 1 CRS, those with a longer duration of CRS-related symptoms (>5 days; grade 1b in modified CRS grading [m-CRS]) had a significantly higher incidence and longer duration of prolonged cytopenia than those whose CRS-related symptoms resolved within 5 days (grade 1a m-CRS). Multivariate analysis revealed that a higher m-CRS grade (grade 1b or 2; hazard ratio [HR], 2.42), higher peak CRP (≥10 mg/dL; HR, 1.66), longer duration of elevated CRP (≥10 days; HR, 1.83), and a decrease in serum inorganic phosphorus concentration (≥30% from baseline; HR, 1.95) were associated with significantly higher cumulative incidence of prolonged neutropenia, as well as anemia and thrombocytopenia. Using these factors, we developed a new predictive scoring model for prolonged hematotoxicity, the KyoTox a-score, which can successfully stratify the incidence and duration of cytopenia independent of the existing model, CAR-HEMATOTOX, which is based on laboratory data at lymphodepletion. Thus, this newly developed post-CAR-T inflammation-dependent score is accurate and useful for predicting prolonged hematotoxicity.

Successful treatment of lung cancer coexisting with B‑cell lymphoma with pembrolizumab following rituximab‑included chemotherapy: A case report

The combined occurrence of lung cancer and B-cell lymphoma, such as mucosa-associated lymphoid tissue (MALT) lymphoma, is rare. The efficacy and safety of immune checkpoint inhibitors (ICIs) remain unknown in this population of patients, and the occurrence of ICI-induced exacerbation of lymphoma is concerning. The present study describes a case of successful treatment with pembrolizumab following rituximab-containing chemotherapy for lung cancer complicated by MALT lymphoma. The patient was a 69-year-old woman diagnosed with MALT lymphoma based on a biopsy of stomach ulcerative lesions, and advanced lung cancer based on a biopsy of a lymph node in the left pulmonary hilum. Complete remission was achieved after one cycle of rituximab and bendamustine therapy for MALT lymphoma. Pembrolizumab monotherapy was subsequently initiated, resulting in a good response for lung cancer without recurrence or exacerbation of the lymphoma. In conclusion, the present study suggested that pembrolizumab, following rituximab-containing therapy, could be a treatment option for patients with lung cancer coexisting with MALT lymphoma.

Methotrexate‑related other iatrogenic immunodeficiency‑associated lymphoproliferative disorder in the CNS and medication‑related osteonecrosis of the jaw occurring simultaneously: A case report

Methotrexate-related other iatrogenic immunodeficiency-associated lymphoproliferative disorder (MTX-OIIA-LPD) is prone to extranodal involvement but rarely involves the central nervous system (CNS). The present study reports a case of MTX-OIIA-LPD of the CNS discovered during medication-related osteonecrosis of the jaw (MRONJ) treatment in a 76-year-old woman with rheumatoid arthritis (RA). The chief complaint of the patient was bone exposure and pain in the right mandibular molar. The patient had been receiving MTX for RA and alendronate sodium hydrate for osteoporosis, followed by denosumab. Treatment was initiated based on a diagnosis of MRONJ. However, the patient experienced lightheadedness and floating dizziness afterwards. Examinations revealed scattered neoplastic lesions in the brain. The histopathological diagnosis was diffuse large B-cell lymphoma. A systemic search also revealed adrenal involvement. Since the patient was taking MTX, a diagnosis of MTX-OIIA-LPD was made and MTX was discontinued. Chemotherapeutic agents were administered since the central lesions became symptomatic. The MTX-OIIA-LPD lesions in the brain and adrenal glands completely resolved 8 months after onset. The physical condition of the patient improved, and the bone-exposed areas became epithelialized. Reports on MTX-LPD in the oral and maxillofacial region are few, which may delay its diagnosis. Therefore, biopsy of oral lesions in patients with MRONJ who are taking MTX and collaboration with related diagnostic departments, such as rheumatology and hematology, must be done to initiate the diagnosis and treatment of extraoral MTX-LPD.

[Severe consciousness disturbance after cord blood transplantation for relapsed T lymphoblastic lymphoma]

T-lymphoblastic leukemia/lymphoma (T-ALL/LBL) has a poor prognosis. Nelarabine has recently shown relatively good results in patients with relapsed or refractory T-ALL/LBL, but requires careful monitoring for neurological complications. A 50-year-old man with early recurrence of T-LBL after allogenic peripheral blood stem cell transplantation received nelarabine monotherapy and achieved complete remission after 1 cycle. He then received umbilical cord blood transplantation, and experienced sustained disturbance of consciousness. He later died of multiple organ failure, and autopsy suggested that nelarabine-induced leukoencephalopathy had caused the disturbance of consciousness. This case suggests that physicians should carefully monitor patients for neurological complications and consider imaging follow-up and consultation with a neurologist.

Impact of Antimicrobial Drug-Drug Interactions on Acute Kidney Injury after Allogeneic Hematopoietic Cell Transplantation

Acute kidney injury (AKI) is one of the major complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The use of multiple antimicrobials is one of the major causes of post-transplantation AKI, owing to the potential nephrotoxicity of each agent and of drug-drug interactions (DDIs). No satisfactory reports on DDIs the field of allo-HSCT have been published. We performed a retrospective analysis to compare the incidence of AKI within 100 days post-transplantation. A total of 465 allo-HSCTs in 416 patients were analyzed, and the cumulative incidence of AKI was 40.0%. AKI was associated with significantly reduced overall survival (hazard ratio [HR], 2.66; 95% confidence interval [CI] 1.95 to 3.55; P < .01) and increased transplantation-related mortality (HR, 4.77, 95% CI, 2.90 to 7.88; P < .01). A higher incidence of AKI was significantly associated with the use of ciprofloxacin, cefepime, tazobactam/piperacillin, meropenem, vancomycin, liposomal amphotericin B, ganciclovir, and foscarnet. Among these drugs, combinations of vancomycin plus tazobactam/piperacillin (HR, 2.23; P = .09 for interaction), ganciclovir plus cefepime (HR, 5.93; P = .04), and ganciclovir plus meropenem (HR, 2.63; P = .12) synergistically increased the risk of AKI, whereas combinations involving teicoplanin did not. This is the first report dealing with DDIs after allo-HSCT, indicating that such combinations should be avoided to preserve renal function and reduce AKI-related morbidity and mortality.

Risk analysis of fluctuating hypercalcemia after leukapheresis in cellular therapy

Optimized management of citrate-induced hypocalcemia is required to provide safe leukapheresis. We prospectively analyzed subjects who underwent leukapheresis for cytotherapy, and evaluated serum ionized (iCa) concentrations before, at the end of, and 1 h after leukapheresis. During leukapheresis, calcium gluconate solution was continuously supplemented intravenously with hourly measurement of iCa. 76 patients including 49 lymphapheresis for chimeric antigen receptor T-cell therapy and 27 stem cell collections were enrolled. Median processing blood volume was 10 L (range, 6-15 L). Fluctuating hypercalcemia, in which the iCa concentration rose above its upper limit 1 h after leukapheresis, was observed in 58 subjects (76.3%). Multivariate analysis revealed that higher ratios of processing blood volume to body weight, more rapid calcium supplementation, and lower iCa concentration at the end of leukapheresis significantly increased elevation of serum iCa concentration by 1 h after leukapheresis. Based on multivariate analyses, we developed a formula and a diagram that accurately estimates serum iCa concentration 1 h post-leukapheresis. This suggests optimal targets for iCa concentration and calcium supplementation rates. In cases with high ratios of processing blood volume to body weight, slowing the rate of blood processing, rather than increasing calcium supplementation should safely alleviate hypocalcemia during leukapheresis without inducing hypercalcemia thereafter.

Successful azacitidine therapy for myelodysplastic syndrome associated with VEXAS syndrome

VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is caused by UBA1 somatic mutations and is characterized by late-onset systemic autoimmune inflammation and blood abnormalities such as cytopenia, vacuolation of myeloid/erythroblastic cells, and myelodysplastic syndrome (MDS). It is often resistant to immunosuppressive therapy, and no treatment strategy has been established. A 65-year-old man presented with palpable erythema, fever, macrocytic anemia, and arthralgia. He was subsequently diagnosed with MDS complicated by Sweet's disease. Treatment with azacitidine was initiated due to suspected skin invasion by MDS cells and resistance of the skin rash to steroid therapy. Next-generation sequencing of bone marrow samples prior to treatment initiation revealed the presence of UBA1 p.M41L (VAF 0.38) and DNMT3A p.L605fs mutations (VAF 0.184). Based on the findings of systemic inflammation, a diagnosis of VEXAS syndrome was made. The fever and skin rash improved with azacitidine therapy. In conclusion, somatic mutations in UBA1 should be explored in patients with MDS exhibiting systemic autoimmune inflammation. Furthermore, azacitidine may be a good treatment option for systemic autoinflammation in MDS associated with VEXAS syndrome.

Significance of Omitting Day 11 Mini-Dose Methotrexate for GVHD Prophylaxis After Unrelated Bone Marrow Transplantation

The combination of calcineurin inhibitors and short-term methotrexate has been used as a standard graft-versus-host-disease (GVHD) prophylaxis in allogeneic hematopoietic stem cell transplantation. Mini-dose methotrexate (mini-MTX), consisting of 5 mg/m²/d on days 1, 3, 6, and 11, is occasionally selected as an alternative considering toxicity. The significance of day 11 administration remains unclear. We performed a retrospective study of 135 cases of unrelated bone marrow transplantation at our institute between 2006 and 2019 and compared the outcomes between day 11 MTX dose omitted (n = 72) and full-doses of mini-MTX (n = 63). In total cohort, the 4-year overall survival (OS) was 58.7 %, and the omitted group showed poor GVHD/relapse-free-survival (P = .01) with comparable OS (P = .11) and relapse-free survival (P = .11). Human leukocyte antigen (HLA) mismatch is a major risk factor for severe GVHD. We analyzed the impact of omitting day 11 MTX in 2 cohorts from HLA matched or mismatched donors. In both cohorts, the omitted group had a higher risk of severe acute and chronic GVHD. In conclusion, the omission of day 11 MTX was associated with a higher risk of severe GVHD. Therefore the omission of the day 11 dose is not recommended.

[Successful treatment of post-allogeneic hematopoietic transplant immune thrombocytopenia with eltrombopag]

A 44-year-old woman in the first remission phase of mixed-phenotype acute leukemia (T-lymphoid and myeloid lineages) suddenly exhibited thrombocytopenia (1.1×10⁴/µl) with generalized petechiae approximately 150 days after bone marrow transplantation (BMT) from a one-locus (HLA-B) mismatched unrelated donor. Until then, the donor bone marrow had smoothly engrafted, and the platelet count had promptly normalized. Despite extensively searching for the triggering agent such as GVHD, graft failure, relapsed leukemia, or adverse drug effects, it could not be determined. Suspecting immune thrombocytopenia secondary to BMT, prednisolone (1 mg/kg/2 days) therapy was initiated, but its effects were unsatisfactory. Next, eltrombopag, a thrombopoietin receptor agonist (TPO-RA), was administered, which exhibited a marked effect on thrombocytopenia, resulting in the withdrawal of prednisolone. Even though the efficacy of eltrombopag against immune thrombocytopenia is well established, limited studies have reported the efficacy and safety of eltrombopag against immune thrombocytopenia after allogeneic stem cell transplantation. Herein we report a case in which thrombocytopenia occurred late after transplantation but was successfully treated with a TPO-RA. In addition, we discuss suspected causative mechanisms and review the literature.

Concurrent Autoimmune Neutropenia and Idiopathic Thrombocytopenic Purpura Associated with IgG4-related Diease

IgG4-related disease (IgG4RD) is a multi-organ disorder characterized by an elevated serum IgG4 level and IgG4-positive plasma cell infiltration of the affected organs, accompanied by tissue fibrosis and sclerosis. Although it can affect any organ, to our knowledge, no cases involving concurrent autoimmune neutropenia and thrombocytopenia have been reported. A 62-year-old man visited our hospital and was diagnosed with IgG4RD accompanied by interstitial pneumonitis, lymphadenopathy, and interstitial nephritis. During his clinical course, he developed autoimmune neutropenia and idiopathic thrombocytopenic purpura. Our case, invoving multiple hematological abnormalities, might help deepen our understanding of the pathophysiology of IgG4RD.

Mycobacterium shigaense sp. nov., a slow-growing, scotochromogenic species, is a member of the Mycobacterium simiae complex

Among non-tuberculous mycobacteria (NTM), the Mycobacterium simiae complex is one of the largest groups, consisting of 18 species of slow-growing mycobacteria. In 2009, a case of NTM-associated infectious skin disease was reported in Shiga Prefecture, Japan. The patient presented with scattered nodules on the chest, back and extremities, and an M. simiae-like organism was isolated from skin biopsy specimens obtained from one of these lesions. Based on several assessments, including multiple-gene analyses, biochemical characterization and drug susceptibility testing, we concluded that this isolate represented a novel species of NTM, and proposed the name 'Mycobacterium shigaense'. Since 2009, five more cases of NTM-associated infectious disease in which there was a suspected involvement of 'M. shigaense' have been reported. Interestingly, four of these six cases occurred in Shiga Prefecture. Here we performed multiple-gene phylogenetic analyses, physiological and biochemical characterization tests, drug susceptibility tests, and profiling of proteins, fatty acids and mycolic acids of eight clinical isolates from the six suspected 'M. shigaense' cases. The results confirmed that all of the clinical isolates were 'M. shigaense', a slow-growing, scotochromogenic species. Here M. shigaense is validly proposed as a new member of the M. simiae complex, with the type strain being UN-152^T (=JCM 32072^T=DSM 46748^T).

High pretransplant hepcidin levels are associated with poor overall survival and delayed platelet engraftment after allogeneic hematopoietic stem cell transplantation

Iron overload is considered a risk factor for mortality in patients with hematopoietic malignancies. Hepcidin is a key regulator of systemic iron balance. We previously reported dynamic changes of serum hepcidin‐25 levels in patients with hematologic malignancies after allogeneic hematopoietic stem cell transplantation (allo‐HSCT). In this study, we retrospectively analyzed the association of pretransplant hepcidin‐25 levels with overall survival (OS), engraftment, and other clinical outcomes of allo‐HSCT in patients with hematologic malignancies. A total of 166 patients were divided into two groups depending on their pretransplant serum hepcidin‐25 levels; their median age was 49.5 years, and the median follow‐up time was 46.8 months. At 3 years, the patients in the high‐hepcidin group had a significantly lower OS than those in the low‐hepcidin group (49.2 vs. 69.0%, respectively; P = 0.006). Multivariate analysis revealed that pretransplant serum hepcidin‐25 level, sex, and disease status were independently associated with OS. The incidence of platelet engraftment was significantly lower in the high‐hepcidin group than in the low‐hepcidin group, whereas no significant differences were observed in neutrophil and reticulocyte engraftments between these groups. Hence, pretransplant serum hepcidin levels can be a marker for predicting delayed platelet recovery after allo‐HSCT.

H-Ferritin Is Preferentially Incorporated by Human Erythroid Cells through Transferrin Receptor 1 in a Threshold-Dependent Manner

Ferritin is an iron-storage protein composed of different ratios of 24 light (L) and heavy (H) subunits. The serum level of ferritin is a clinical marker of the body's iron level. Transferrin receptor (TFR)1 is the receptor not only for transferrin but also for H-ferritin, but how it binds two different ligands and the blood cell types that preferentially incorporate H-ferritin remain unknown. To address these questions, we investigated hematopoietic cell-specific ferritin uptake by flow cytometry. Alexa Fluor 488-labeled H-ferritin was preferentially incorporated by erythroid cells among various hematopoietic cell lines examined, and was almost exclusively incorporated by bone marrow erythroblasts among human primary hematopoietic cells of various lineages. H-ferritin uptake by erythroid cells was strongly inhibited by unlabeled H-ferritin but was only partially inhibited by a large excess of holo-transferrin. On the other hand, internalization of labeled holo-transferrin by these cells was not inhibited by H-ferritin. Chinese hamster ovary cells lacking functional endogenous TFR1 but expressing human TFR1 with a mutated RGD sequence, which is required for transferrin binding, efficiently incorporated H-ferritin, indicating that TFR1 has distinct binding sites for H-ferritin and holo-transferrin. H-ferritin uptake by these cells required a threshold level of cell surface TFR1 expression, whereas there was no threshold for holo-transferrin uptake. The requirement for a threshold level of TFR1 expression can explain why among primary human hematopoietic cells, only erythroblasts efficiently take up H-ferritin.

An AKI biomarker lipocalin 2 in the blood derives from the kidney in renal injury but from neutrophils in normal and infected conditions

BACKGROUND

Lipocalin 2 (LCN2 or neutrophil gelatinase-associated lipocalin) is a secretory protein discovered from neutrophils, which accumulates in the blood and urine during acute kidney injury (AKI) and in the blood by bacterial infection. Little is known about the tissue source and molecular forms of this protein under normal and pathophysiologic conditions.

METHODS

By sandwich ELISA, serum and urinary LCN2 levels were measured in 36 patients with hematologic malignancies who transiently became neutropenic by stem cell transplantation (SCT). To evaluate contribution of neutrophil-derived LCN2 in the physiologic blood LCN2 concentrations, we examined CCAAT/enhancer-binding protein ε (C/EBPε) knockout mice, which lack mature neutrophils.

RESULTS

In patients without AKI and bacterial infection, at 1 week after SCT, the median blood neutrophil counts became zero and serum LCN2 levels were decreased by 76 ± 6 % (p < 0.01), but urinary LCN2 levels were not altered. During neutropenic conditions, bacterial infection caused only a modest rise of serum LCN2 but AKI produced a marked rise of serum and urinary LCN2 levels. Serum LCN2 concentrations in C/EBPε knockout mice were reduced by 66 ± 11 % compared to wild-type mice (p < 0.05). Blood LCN2 existed predominantly in high molecular weight forms (>100 kDa), while urinary LCN2 was mainly in low molecular weight forms.

CONCLUSION

Our findings suggest that neutrophils are the major source of circulating LCN2 in normal and infected conditions, whereas blood and urinary LCN2 mainly derive from the kidney during AKI, and that the molecular forms and regulation of blood and urinary LCN2 are clearly distinct.

Immune pancytopenia associated with a leukemic B-cell tumor carrying t(14;18)(q32;q21) translocation

We report a 75-year-old man who was initially suggested to have acute leukemia. The hemoglobin level was 3.8 g/dL, white cell count was 7,700/µL with an absence of mature neutrophils and 69.0% leukemic cells, and platelet was 0.4 × 10(4)/µL. Coombs' antiglobulin test was positive. Leukemic cells were CD5(-), CD10(+), CD20(+), CD23(-), and IgG/λ(dim+). The bone marrow consisted of normal hematopoietic precursors, whereas fluorescence in situ hybridization detected the BCL2/IgH fusion gene. He was treated with rituximab-containing chemotherapy, resulting in the resolution of pancytopenia. The underlying disease was a leukemic B-cell tumor with t(14;18)(q32;q21), and the pancytopenia was mainly caused by autoimmune mechanisms.

Pretransplant serum ferritin and C-reactive protein as predictive factors for early bacterial infection after allogeneic hematopoietic cell transplantation

Although fluoroquinolones or other antibiotics are commonly used to prevent bacterial infections after hematopoietic cell transplantation (HCT), because of the growing presence of multidrug-resistant microorganisms, it is important to identify patients who are more likely to benefit from antibacterial prophylaxis. To evaluate risk factors for early bacterial infection after allogeneic HCT, we retrospectively analyzed clinical data for 112 consecutive adult patients with hematological malignancies who received transplants without any antibacterial prophylaxis. The cumulative incidence of bacterial infection at 30 days after transplantation was 16%. Among various pre-transplant factors, only high serum ferritin (>700 ng/mL, 47 patients) and high C-reactive protein (CRP) (>0.3 mg/dL, 28 patients) levels were significantly associated with the development of bacterial infection in a multivariate analysis (hazard ratio (95% confidence interval): ferritin, 4.00 (1.32-12.17); CRP, 3.64 (1.44-9.20)). In addition, septic shock and sepsis with organ failure were exclusively observed in patients who had high ferritin and/or high CRP levels. These results suggest that pretransplant serum ferritin and CRP levels can be useful markers for predicting the risk of early bacterial infection after allogeneic HCT. It may be prudent to limit antibacterial prophylaxis to patients with predefined risk factors to ensure the safety of HCT with the use of fewer antibiotics.

Clinical significance of serum hepcidin levels on early infectious complications in allogeneic hematopoietic stem cell transplantation

The association of iron overload with complications of allogeneic hematopoietic stem cell transplantation (HSCT) has been suggested in previous studies. Because hepcidin plays a central role in the regulation of iron homeostasis, we analyzed the association between pretransplant serum hepcidin-25 levels and early infectious complications after allogeneic HSCT. We studied 55 consecutive adult patients with a median age of 47 years (range: 20-64 years) who underwent allogeneic HSCT for hematologic malignancies at our institution. Thirty-two patients had myelogenous malignancies; the remaining 23 had lymphogenous malignancies. The median pretransplant serum hepcidin level of patients in the study was 21.6 ng/mL (range: 1.4-371 ng/mL), which was comparable to that of healthy volunteers (median: 19.1 ng/mL [range: 2.3-37 ng/mL]; n = 17). When cumulative incidences of documented bacterial and cytomegalovirus (CMV) infections at day 100 were compared according to pretransplant hepcidin-25 levels, the incidence of bacterial, but not CMV, infection, was significantly higher in the high-hepcidin group (> or = 50 ng/mL; n = 17) than in the low-hepcidin group (<50 ng/mL; n = 38) (65% [95% confidence interval, 38%-82%] versus 11% [3%-23%]; P < .001). This finding was confirmed by multivariate Cox analysis adjusted for confounders, including pretransplant ferritin and C-reactive protein (CRP) levels. No fungal infection was documented in either group. These results suggest that the pretransplant serum hepcidin-25 level may be a useful marker for predicting the risk of early bacterial complications after allogeneic HSCT. Larger prospective studies are, however, warranted to confirm our findings.

[Epstein-Barr virus-associated B cell lymphoproliferative disorder complicated in adult T-cell leukemia]

Adult T-cell leukemia (ATL) is accompanied by remarkably impaired cellular immune responses. Reports on the simultaneous development of ATL and Epstein-Barr virus-associated lymphoproliferative disorders (EBV-LPD) are, however, quite rare. A 53-years-old man was admitted to our hospital because of multiple bilateral pulmonary nodules, skin rash, lymphadenopathy, and hypercalcemia. The smear preparation of peripheral blood demonstrated pathological lymphocytes with lobulated nuclei. They expressed CD2, CD3, and CD25, but did not express either CD4 or CD8. In addition, he was positive for Human T-cell leukemic virus type-I (HTLV-I), and monoclonal integration of HTLV-I provirus was detected in peripheral blood. Unexpectedly, inguinal lymph node biopsy showed polyclonal proliferation of EBV-positive large and bizarre-shaped B cells, and monoclonal growth of large abnormal T cells. He was diagnosed as having acute type ATL complicated by EBV-LPD. Chemotherapy for ATL effectively decreased the tumor burden of ATL, but persistent high fever developed suddenly on the 68th day after admission, and he died of multi-organ failure with severe metabolic acidosis. At the time of multi-organ failure, viral load had increased strikingly, suggesting that the progression of EBV-LPD might have been responsible for multi-organ failure in this case.

Leukemic and meningeal relapse of CD5+ intravascular large B-cell lymphoma with down-modulation of CD20 after rituximab therapy

Although CD20- relapses of B-cell lymphoma following rituximab therapy have increasingly been reported recently, coexistence of both the original and selected clones on relapse in a single patient have not been described. We experienced such a case with rare CD5+ intravascular lymphomatosis (IVL). A 46-year-old woman was admitted because of IVL complicated with cauda equina syndrome and pulmonary infarction. Complete remission was successfully achieved with multidrug chemotherapy in combination with rituximab. However, the disease recurred after 8 months with leukemic progression and meningeal involvement. The phenotype of the abnormal lymphocytes in the peripheral blood was fundamentally the same (CD20+CD5+CD10-CD19+CD23-sIglambda+) as that of the cells in the cerebrospinal fluid (CSF). However, CD20 expression was decreased remarkably compared with that in the CSF and that in the bone marrow before therapy. The targeting of CD20 molecules on the tumor cell surface by rituximab may have provided a selective pressure on lymphoma cells. The escape phenomenon of the lymphoma cells from rituximab was observed by simultaneously comparing the CD20 expression of cells in the peripheral blood and in a site of sanctuary from rituximab, the CSF.

[Tumor microembolism presenting as characteristic patterns of pulmonary perfusion on lung scanning: a case report]

A 55-year-old man presented with tumor microembolism manifesting as characteristic patterns of pulmonary perfusion on lung scanning. He had a 2-week history of dyspnea and general fatigue. Echocardiography demonstrated right ventricular enlargement. Computed tomography of the chest was normal. Lung perfusion imaging showed multiple subsegmental peripheral defects, which were characteristic of tumor embolism. Ultrasonography and computed tomography of the abdomen revealed multiple enlargement of the lymph nodes. Upper gastrointestinal panendoscopy showed gastric cancer. At 10 days after admission, he suffered cardiac arrest and died despite resuscitative efforts. Histological examination revealed pulmonary arterial obstruction with tumor cells, and poorly differentiated adenocarcinoma in the stomach and lymph nodes. This case emphasizes the need to include tumor microembolism in the differential diagnosis of dyspnea, even if there is no evidence of an underlying malignant tumor.

Impaired gastric slow waves induced by spatial disorientation and effect of domperidone

OBJECTIVES

Our aims were to investigate the dominant frequency and regularity of gastric myoelectrical activity during motion sickness induced with the advanced spatial disorientation demonstrator (ASDD) and to evaluate the effect of domperidone on gastric myoelectrical activity and gastrointestinal symptoms during motion sickness.

METHODS

Thirteen healthy volunteers participated in this study. This study was executed using the ASDD, which could duplicate several spatial disorientation phenomena in a safe, controlled environment. Each subject participated in two sessions and received oral administration of 10 mg domperidone before the study in one of the sessions. In each session, three 15-min EGG recordings were made before, during, and after rotation. The symptoms were scored by Graybiel's scale of motion sickness before and after rotation. All EGG data were subjected to computerized spectral analysis to obtain the percentage of normal 2-4 cycles/min (cpm) slow waves, percentage of tachygastria, EGG dominant frequency and power, and instability coefficient of the dominant frequency.

RESULTS

We have found that the percentage of normal gastric slow wave was decreased (control session: 86.2 +/- 4.0% vs 70.0 +/- 5.4%, p < 0.01; domperidone session: 82.7 +/- 4.6% vs 69.8 +/- 5.6%, p < 0.03) and the percentage of tachygastria was increased (control session: 8.7 +/- 3.2% vs 17.8 +/- 5.6%, p < 0.01; domperidone session: 9.2 +/- 3.3% vs 18.1 +/- 3.5%, p < 0.01) after rotation in both sessions. The minute-by-minute variation of the gastric slow wave frequency was significantly increased during rotation in both sessions (control: 0.74 +/- 0.16 vs 1.35 +/- 0.19, p < 0.01; domperidone: 0.90 +/- 0.20 vs 1.47 +/- 0.17, p < 0.01). Domperidone did not prevent dysrhythmia or the symptoms of motion sickness.

CONCLUSIONS

The percentage of normal gastric slow waves is decreased and the percentage of tachygastria is increased with spatial disorientation. Domperidone does not prevent gastric dysrhythmia or the symptoms of motion sickness induced with spatial disorientation.

Visual influence on the magnitude of somatogravic illusion evoked on advanced spatial disorientation demonstrator

BACKGROUND

The somatogravic illusion (SGI) is a kind of spatial disorientation caused by a linear sustained acceleration. Pilots believe that visual cues, such as a visible horizon or texture flow, reduce this illusion. This study was performed to evaluate the influence of visual stimuli on the SGI using the Advanced Spatial Disorientation Demonstrator (ASDD).

METHODS

There were eight healthy males who were exposed to a 0.58 g x axis linear acceleration on the ASDD, where the direction of the resultant gravitoinertial force was equivalent to 30 degrees pitch-up. One of the following visual stimuli was presented during each acceleration: BLANK (no visual cues); HORIZON (a visible horizon without motion); and TEXTURE (vertical lines moving toward the subject evoking vection). The subjective magnitude of the SGI in ordinal scale was observed; and in interval scale, the deviation of the moving point kept at the subjective horizon was observed. The differences among visual stimuli were analyzed.

RESULTS

The subjective magnitude of the SGI (p < 0.01) and the deviation of the moving point (p < 0.05) were significantly smaller in HORIZON than in BLANK and TEXTURE. No difference was demonstrated between BLANK and TEXTURE. The linear vection produced by the TEXTURE stimulus did not affect the SGI.

CONCLUSION

The data indicated that the presence of a visible horizon reduced the magnitude of the SGI. On the other hand, the presence of a vection stimulus did not influence the magnitude of the SGI.

Repression of motility and flagellin production at 37 degrees C is stronger in Listeria monocytogenes than in the nonpathogenic species Listeria innocua

Listeria monocytogenes and Listeria innocua differ markedly in virulence but are indistinguishable by classical taxonomic criteria. Both species are actively motile and produce abundant flagellin at 22 degrees C. We have found, however, noticeable differences between L. monocytogenes and L. innocua in motility and flagellin production at 37 degrees C. At this temperature, L. monocytogenes strains were virtually nonmotile and produced little or no detectable flagellin, whereas strains of L. innocua were frequently motile and produced substantial amounts of flagellin. This flagellin was recognized by a Listeria genus-specific monoclonal antibody that also recognized flagellin produced at 22 degrees C. These results suggest differential regulation of flagellin production between L. monocytogenes and L. innocua at 37 degrees C.

Monoclonal antibodies with a high degree of specificity for Listeria monocytogenes serotype 4b

Strains of Listeria monocytogenes serotype 4b account for a large fraction of sporadic listeriosis cases, as well as all major food-borne epidemics attributed to this pathogen. We have identified a set of three monoclonal antibodies which showed a high degree of specificity for strains of L. monocytogenes serotype 4b. Two of these antibodies (c74.33 and c74.180, isotypes immunoglobulin M [IgM] and IgG3, respectively) recognized all serotype 4b strains, whereas antibody c74.22 (isotype IgG1) failed to recognize certain epidemic-associated strains. The corresponding antigens were located on the surface of the bacteria and were expressed following bacterial growth in different media and over a wide range of temperatures (4, 22, and 37 degrees C). Heating L. monocytogenes cells at 80,90, or 100 degrees C abolished reactivity for c74.22 but not for c74.33 MAb. These MAbs were negative for all of the non-Listeria strains tested, including representatives of several gram-negative and gram-positive species. The surface antigen recognized by c74.22 appeared to be associated with the ability of the bacteria to enter (invade) mammalian cells in culture.

Hypoxia-induced fatal aircraft accident revealed by voice analysis

The voice communication was the only clue of the fatal F-104J accident encountered during high-altitude intercept procedures, and it was analysed to prove the presence of hypoxia as a causal factor. A simulated low-pressure chamber flight was undertaken, and the subject's voice, saying the same words as the pilot, was analyzed in the same way. Comparison of these two voices revealed a similarity in characteristic changes of the sound spectrum and time course. The blurred formation of formant, fundamental, and harmonic frequencies, as well as the obscured gap in pre-vocal cord opening time (VOT) of the sound spectrogram, were thought to be the effects of hypoxia. Lowered fundamental frequency of the pilot's voice, even at the stressful period of attack, has strongly suggested decreased vigilance due to hypoxia. Through these findings, it was concluded that the cause of the accident was probably hypoxia in the pilot.

Seroepidemiology of human syncytial virus: antibody prevalence in the Pacific

A seroepidemiological survey of the human syncytial (foamy) virus was done by means of an indirect immunofluorescence test on 1,717 sera from nine different Pacific island territories. The specificity of the reaction was verified by neutralization tests. The study indicated that the virus is ubiquitous in this part of the world, with no region being entirely free of antibody. The antibody prevalence ranged from a low of 1.2% in Ponape to a high of 15.6% in the Cook Islands. The average prevalence for the nine insular communities was 6.9%.