Yoshiko Fujimoto

Absence of pseudomembranes in Clostridium difficile-associated diarrhea in patients using immunosuppression agents.

Objective. Clostridium difficile is a major cause of diarrhea in hospitalized patients. Although pseudomembranes are crucial evidence for diagnosis of C. difficile-associated diarrhea (CDAD), some cases do not show any pseudomembranes. The aim of this study was to verify the hypothesis that pseudomembranes are not generated in immunosuppressed patients because of the absence of immunoreactions. Material and methods. We investigated the endoscopic findings of patients with ulcerative colitis (UC) or who had received hematopoietic stem cell transplantation, and who presented with C. difficile toxin A and had undergone colonoscopy between April 2002 and July 2007 at our institutes. Results. In 4 patients the diagnosis was UC and C. difficile infection, and in another 4 patients the diagnosis was CDAD after hematopoietic stem cell transplantation. None of these cases showed pseudomembranes. Shallow ulcers were found in all four cases with UC. Only non-specific findings were obtained for the CDAD patients after hematopoietic stem cell transplantation. Conclusions. Pseudomembranes, the typical evidence for CDAD, were not detected in any patients using immunosuppressive agents. Additional bacterial examination is therefore essential when UC becomes exacerbated and when patients present with diarrhea after hematopoietic stem cell transplantation, even in the absence of pseudomembranes.

Tocilizumab is effective for pulmonary hypertension associated with multicentric Castleman’s disease

A 38-year-old man, diagnosed as having multicentric Castleman’s disease (plasma cell type) in 1995, had been treated with melphalan and prednisolone or prednisolone alone, but there was no remarkable response. In 2002, he was admitted to our hospital with a chief complaint of increasing dyspnea on effort. Laboratory data showed high serum IgG (10050 mg/dl), interleukin-6 (37.9 ng/ml), and vascular endothelial growth factor (VEGF 1920 pg/ml) levels. In addition, serum viscosity was very high (6.0 cp). Electrocardiogram, echocardiogram, and cardiac catheterization demonstrated pulmonary hypertension (PH). There were no other demonstrable causes of PH suggesting that PH was due to hyperviscosity syndrome and high VEGF level. He was treated with plasmapheresis, resulting in a transient improvement of dyspnea. Then, he was given humanized anti-interleukin-6 receptor antibody (tocilizumab), which resulted in the dramatic improvement of dyspnea and PH a few weeks later. PH is a rare complication of MCD, and could be successfully treated with tocilizumab.

Risk factors for infection in haematology patients treated with rituximab

Objectives:  Although rituximab therapy is not considered to be closely associated with infection, there have been reports of serious infections in patients treated with rituximab. We performed a statistical retrospective analysis to clarify the risk factors for infection in patients receiving rituximab therapy.

Effectiveness and Limitation of Gamma Knife Radiosurgery for Relapsed Central Nervous System Lymphoma: A Retrospective Analysis in One Institution

We describe 6 patients with relapsed central nervous system lymphoma (CNSL) treated with Gamma Knife radiosurgery (GKR). The histologic diagnosis in all 6 patients was diffuse large B-cell lymphoma without human immunodeficiency virus infection. Two patients had intracranial relapse of primary CNSL, and the remaining 4 had CNS relapse of systemic lymphoma. All patients were treated with GKR without severe adverse effects, and all but 1 patient received subsequent chemotherapy shortly after GKR. Four patients showed a complete response, and the remaining 2 patients had a partial response or stable disease. Although the neurologic symptoms disappeared or improved markedly in all patients, all of the diseases recurred or progressed 3 to 13 months after the first GKR. A second GKR was eventually performed in 4 patients. The median overall survival and progression-free survival times after the first GKR were 17 and 11 months, respectively. In our experience, GKR seems to be a useful procedure for the treatment of relapsed CNSL, because it facilitates excellent local control in a short-term treatment period without severe complications, although the efficacy period is not long enough.

Optimized dosage and frequency of cefozopran for patients with febrile neutropenia based on population pharmacokinetic and pharmacodynamic analysis

OBJECTIVES To establish a cefozopran (a fourth-generation cephem) population pharmacokinetic model using patient data and use it to explore alternative dosage regimens that could optimize the currently used dosing regimen to achieve higher likelihood of pharmacodynamic exposure against pathogenic bacteria. METHODS We conducted a prospective clinical trial of cefozopran for haematological patients with febrile neutropenia (FN). Twenty-two patients (30 episodes) were selected to receive intravenous cefozopran every 8 h on a daily basis. We gathered concentration data and performed the NONMEM program. The Monte Carlo simulation was performed to assess the pharmacodynamic exposure based on the population pharmacokinetics and MIC. RESULTS The NONMEM program demonstrated that a two-compartment model provided a best fit for the data, that is, CL of 4.62 (L/h), V1 of 10.3 (L), Q of 4.47 (L/h), and V2 of 4.48 (L). On the basis of the Japanese national surveillance findings for Pseudomonas aeruginosa, methicillin-sensitive Staphylococcus aureus, coagulase-negative Staphylococcus, viridans group streptococci, Escherichia coli and Klebsiella pneumoniae, Monte Carlo simulation data showed that probability of target attainment(T>MIC = 70%) is 67% to 97% for dosing every 8 h, and 48% to 88% for dosing every 12 h. For the patients in whom the efficacy of cefozopran could be evaluated, 17 of 22 patients (77.2%) survived the episode of FN without requiring further antibacterial treatment. CONCLUSIONS Our study proved that Monte Carlo simulation based on population pharmacokinetics can determine optimized dosage and method. The optimal regimen for this cephem was found to be three times daily.

Population pharmacokinetics of itraconazole solution used as prophylaxis for febrile neutropenia

Although administration of antifungal agents, such as itraconazole (ITC) solution, for prophylaxis is the most promising strategy for the treatment of haematological malignancies, little is known about the population pharmacokinetic (PK) parameters. A clinical study was conducted to identify PK parameters for the administration of 200mg/day ITC solution used as prophylaxis for febrile neutropenia in patients undergoing treatment. The study population comprised six patients. NONMEM software was used to estimate PK parameters. Clearance, volume of distribution and the absorption rate constant were 12.7 L/h, 333 L and 1.72 h(-1), respectively. These parameters were different from a previous study to large extent, which may be due to differences in intended patients. These differences strongly suggest that establishment of population pharmacokinetics is essential for planning a prospective clinical trial. Assuming a normal distribution, we predicted the trough concentrations of 94.5% of the patients receiving 200 mg/day ITC solution to be >250 ng/mL, indicating that administration of 200mg/day might be suitable for prophylaxis. This pilot study presents a basic PK model of ITC solution in Japanese haematological patients for the establishment of optimal administration. Large-scale studies will be necessary in the future to determine population PK parameters with covariates.

Immunoglobulin light chain gene translocations in non-Hodgkin's lymphoma as assessed by fluorescence in situ hybridisation

In non‐Hodgkin’s lymphoma (NHL), the majority of translocations involve the immunoglobulin heavy chain gene (IGH) locus, while a few involve the immunoglobulin light chain gene (IGL) locus, consisting of the kappa light chain gene (IGκ) and the lambda light chain gene (IGλ). Although many reports have dealt with the translocation and/or amplification of IGH in NHL, only a few have identified IGL translocations. To identify cytogenetic abnormalities and the partner chromosomes of IGL translocations in NHL, we performed dual‐colour fluorescence in situ hybridisation (DC‐FISH) and spectral karyotyping (SKY) in seven NHL cell lines and 40 patients with NHL. We detected IGL translocations in two cell lines and nine patients: four patients with diffuse large B‐cell lymphoma, three with follicular lymphoma, one with extranodal marginal zone B‐cell lymphoma of mucosa‐associated lymphoid tissue and one with mantle cell lymphoma. Five distinct partners of IGλ translocation were identified by SKY analysis: 3q27 in three patients, and 1p13, 6p25, 17p11.2 and 17q21 in one patient each. Three cases featured double translocations of IGH and IGL. These findings warrant the identification of novel genes 1p13, 6p25, 17p11.2 and 17q21.

Monosomies 7p and 12p and FLT3 internal tandem duplication: possible markers for diagnosis of T/myeloid biphenotypic acute leukemia and its clonal evolution

Biphenotypic acute leukemia co-expressing T-lymphoid and myeloid markers is rare, accounting for less than 1% of acute leukemias. However, several clinical characteristics including male predominance, frequent lymphadenopathy and unfavorable outcome have been identified. Recurrence of monosomies 7p and/or 12p in T/myeloid biphenotypic acute leukemia has been reported. We treated a patient with T/myeloid biphenotypic acute leukemia showing clonal chromosomal and genetic abnormalities including dic(7;12)(p11;p11) and Fms-like tyrosine kinase 3 (FLT3)-internal tandem duplication. Cytogenetic analysis of both bone marrow and lymph node cells disclosed that the patient’s lymph node leukemia cells had chromosomal abnormalities in addition to dic(7;12). Our findings suggest that the leukemia cells of systemic lymphadenopathy had evolved as secondary cells from marrow leukemia cells. The patient was successfully treated with induction chemotherapy for acute myeloid leukemia followed by allogeneic bone marrow transplantation.

Clostridium difficile-associated diarrhea with hematochezia is associated with ulcer formation.

Objective. Clostridium difficile-associated diarrhea (CDAD) is a well-known iatrogenic infection with typical endoscopic features including pseudomembranes and intervening normal mucosa. Clinically, diarrhea frequently occurs, but occurrence of hematochezia is rare. The objective of this study was to investigate the background and endoscopic features of CDAD patients with hematochezia. Material and methods. The endoscopic and clinical findings in 12 patients who showed evidence of C. difficile toxin A and who underwent colonoscopy between April 2002 and July 2007 were investigated retrospectively. Results. Eight patients were diagnosed as having CDAD and 4 patients had a diagnosis of ulcerative colitis. Six of the patients with CDAD presented with hematochezia, and 4 of them were diagnosed with hematological malignancies and received anticancer chemotherapy. Colonic ulcer was demonstrated in all CDAD patients with hematochezia, and bleeding from the ulcer was endoscopically confirmed in all of them. Conclusions. CDAD accompanied by hematochezia is closely associated with ulcer formation. Ulcers are thought to occur during recovery from nadir after anticancer treatment, and white blood cells appear to be essential for their formation. Physicians should therefore pay close attention to the occurrence of colonic ulcer, especially in patients with CDAD during recovery from nadir.