Combined genogroup I and II norovirus infection at a nursery.

From November 2004 to April 2005, 5 cases of norovirus (NoV) occurred in Sakai City, Japan. These were all diffuse outbreaks due to infections with genogroup II genotype 4 (GII/4) virus strains. Similar outbreaks occurred throughout Japan; hence, GII/4 was assumed to be the prevalent NoV type. However, a NoV outbreak that occurred at a nursery in May 2005, was caused by infections with GI/4 and GII/6 viruses, respectively, from different children. The time course of newly infected patients showed that this nursery outbreak had a two-peak pattern, with the peak numbers of patients occurring on May 19 and May 22. Virological examination and epidemiological research could not determine whether the GI and GII NoV infections occurred at the same time, or whether there was a time difference in their appearance in the nursery. From this outbreak, it is clear that the timing of obtaining samples and obtaining the minimal necessary number of primary samples are essential for accurate epidemiological information to be obtained. In addition, we detected genotypes that were different from the previously prevalent genotypes, which raises the possibility of more frequent NoV infection or a change in the prevalent NoV genotype in this setting. In conclusion, it is difficult to predict outbreaks of NoV; however, through vigilant and early collection and analysis of later samples throughout an outbreak, it is possible to understand the prevalence and perhaps trace the source of NoV infections.

[Clinical analysis of antibiotic treatment for febrile neutropenia].

Patients with hematological malignancies and aplastic anemia become complicated by critical infections, which are one of the common causes of death in many cases. This is a retrospective investigation of the factors that affect the efficacy of antibiotic treatment of febrile neutropenia (FN). The subjects consisted of 98 cases that developed FN during their hospitalization in this department and received antibiotics as a first-line treatment. Parameters evaluated were age, gender, with or without administration of granulocyte-colony stimulating factor (G-CSF), with or without hematopoietic transplantation, the number of antibiotics, the type of antibiotics, the highest level of C-reactive protein (CRP), with or without antifungal prophylaxis, the duration of neutropenia, and the number of neutrophils before and after the administration of antibiotics. Logistic analysis was used for statistical evaluation. With univariate analysis, significant clinical efficacy was observed with the use of carbapenems (p = 0.0009, Odds; 4.58) when the number of neutrophils was not less than 500/microL (P < 0.0001, Odds: 14.1) after administration of antibiotics. Furthermore, even when multivariate analysis was performed, significant clinical efficacy was observed independently in the use of carbapenems (P = 0.02, Odds: 3.73) and when the number of neutrophils was not less than 500/microL (P < 0.0001, Odds: 10.4) after administration of antibiotics. In this investigation, as a first-line treatment of FN, carbapenem antibiotic is recommended as a primary choice, when the number of neutrophils was expected to decrease after administration.

Infliximab for the treatment of severe steroid refractory acute graft-versus-host disease in three patients after allogeneic hematopoietic transplantation.

Acute graft-versus-host disease (aGVHD) is a serious complication of allogeneic peripheral blood stem cell transplantation (PBSCT). Patients with severe aGVHD not responding to treatment with steroids have a poor prognosis. We treated three patients with severe aGVHD refractory to steroids with infliximab. Patients (MDS 1, NHL 1, ALL 1) developed grade II-IV GVHD at a median of 13 days (range 9-17) after non-myeloablative PBSCT (HLA mismatched). All patients had received treatment with high-dose steroids for a median of 7 days (range 7-10) in addition to mycophenolate mofetil (MMF) (one). Infliximab was given in 3 weekly doses of 5 mg/kg. In one of three patients a partial resolution of diarrhea and minor improvement of skin were observed. One patient died with refractory GVHD. Infliximab is apparently an effective drug for the treatment of aGVHD, but can be more effective at doses of 5 mg/kg or higher and/or by administering it repeatedly every week.

[A case of amelanotic melanoma of the nasal cavity].

A 68-year-old male visited Hospital A for treatment of epistaxis, his chief complaint. He was told that he had an easily-bleeding tumor in the nasal cavity. Based of biopsy, a diagnosis of amelanotic melanoma was made. Operation was performed for removal of the tumor. About 8 months after discharge, he visited Hospital B with complaints of lumbar pain and epistaxis. After biopsy at Hospital B, malignant lymphoma (diffuse large cell) was diagnosed, and the patient was referred to our hospital. On bone marrow puncture and biopsy, tumor cell infiltration was observed. Flow cytometric surface marker analysis revealed that these tumor cells were negative for CD45. Results of HE staining of the nasal cavity tumor were insufficient for diagnosis, and staining by immunohistochemistry was necessary to confirm the diagnosis. On immunohistochemical staining of the nasal cavity tumor tissue and bone marrow biopsy tissue, LCA, L26 and UCHL-1 were negative, and S-100 and HMB-45 positive. Recurrence of amelanotic melanoma accompanied by bone marrow infiltration was therefore diagnosed. The incidence of amelanotic melanoma with primary lesions in the nasal cavity is low. However, in making the diagnosis of a nasal cavity lesion, the possibility of such a melanoma should be kept in mind. In many cases, it is difficult to diagnose amelanotic melanoma with HE staining alone, and immunohistochemistry must be used.

[Primary malignant lymphoma arising from the nipple and areolar area of the breast].

A 56-year-old woman noticed soreness and swelling in the right nipple. Two weeks later, she noticed a mass in the outer lower region of the right areolar area, which was excised and the pathology of which was consistent with diffuse large B cell lymphoma (DLBCL). She was admitted when the right nipple mass was noted to be increasing, and was diagnosed as having stage I lymphoma. Her nipple mass was excised, and the pathology was consistent with DLBCL. CHOP therapy was administered three times and she was judged as having complete remission. Malignant lymphoma accounts for 0.15-0.17% of primary breast malignancies. Though the nipple and areolar area seem to be a rare primary site, this should be recognized as a sentinel zone for malignant lymphoma.

Automated analyzer evaluation of reticulocytes in bone marrow and peripheral blood of hematologic disorders.

The R-3000 reticulocyte analyzer uses flow cytometry with an argon laser as its light source. This analyzer stains residual RNA with auramine O to provide a reticulocyte maturation differential. Using the R-3000, we analyzed 119 samples of bone marrow (BM) and peripheral blood (PB) from 111 patients with hematologic disorders. Parameters were reticulocytes, immature reticulocyte fraction (IRF) percentage in BM and PB, BM/PB reticulocyte ratio, and BM/PB IRF ratio. Reticulocytes and IRF percentage in BM were significantly higher than in PB (p < 0.01). There was also a good correlation between reticulocyte percentages in BM and in PB (r = 0.81). Patients were classified into a normal group (without anemia) and an anemia group. Furthermore, the anemia group was classified into three groups: group 1: cases with hematopoietic dysfunction; group 2: cases in bone marrow recovery phase after chemotherapy and hematopoietic stem cell transplantation, and hematologic disorders with bone marrow accelerative phase, and group 3: cases with ineffective hematopoiesis (myelodysplastic syndrome). The mean reticulocyte percentage of the normal group was 2.3 +/- 1.1%, which was close to the normal value in BM. The BM/PB reticulocyte ratio of group 3 was statistically higher than that of groups 1 and 2. This indicates that group 3 had ineffective erythropoiesis and that the BM/PB ratio is a useful indicator for the diagnosis of myelodysplastic syndrome.

Possible automatic cell classification of bone marrow aspirate using the CELL-DYN 4000 automatic blood cell analyzer.

In clinical hematology, the demand for bone marrow aspiration testing is increasing. However, conventional automatic blood cell analyzers cannot completely analyze erythroblasts, and evaluation has mainly been performed by visual examination (the microscopic method). Using the CELL-DYN 4000 automatic blood cell analyzer (CD4000) (Abbott Laboratories, North Chicago, IL), specific recognition and classification of erythroblasts by DNA staining is possible. In the present study, using bone marrow blood collected from normal subjects and patients with hematological malignancy, we classified cells by the microscopic method and with the CD4000, and compared the results. Good correlations were found for total nucleated cell count (TNCC), neutrophils, lymphocytes, erythroblasts, and the myeloid series to erythroid series (M/E) ratio. It is possible to detect blasts that emerge in patients with hematological malignancy using the blast flag system installed on the CD4000. Since all of the items can be analyzed in about 80 sec with the CD4000, cells in bone marrow aspirates can be classified faster with this apparatus than by the microscopic method. Therefore, analysis of bone marrow aspirates with this apparatus appears to be very useful not only for laboratory testing but also for clinical screening.

Automatic analysis of normal bone marrow blood cells using the XE-2100 automated hematology analyzer.

The bone marrow aspiration test conventionally has been performed by visual methods, using a light microscope, because automatic blood cell analyzers cannot adequately capture erythroblasts and immature granulocytes (IGs) (Tatsumi et al.: Osaka City Med J 1988;34:135-146; Tatsumi et al.: Am J Clin Pathol 1986;86:50-54). With the development of the XE-2100 automatic blood cell analyzer (Sysmex Corporation, Kobe, Japan) in 1999, the classification of erythroblasts and IGs by means of flow cytometry (Zini et al.: Infus Ther Transfus Med 2001;28:277-279; Briggs et al.: Sysmex J Int 1999;9:113-119) became possible. In the present study we classified cells in 65 bone marrow aspiration specimens by the microscopic method and with the XE2100, and compared the results. A good correlation was found in the nucleated red blood cell (NRBC), white blood cell (WBC), and total nucleated cell (TNC) counts; the myeloid/erythroid ratio (M/E ratio); neutrophils, lymphocytes, eosinophils, and IGs in the immature myeloid information (IMI) channel; and the total cell count. These items can all be analyzed in about 54 sec with the XE2100, which is faster than with the microscopic method. Therefore, analysis of bone marrow aspiration specimens with this apparatus appears to be very useful for clinical screening as well as laboratory testing.