Eiichi Ohtsuka

Human Herpesvirus 6 DNA in Plasma after Allogeneic Stem Cell Transplantation: Incidence and Clinical Significance

BACKGROUND Human herpesvirus 6 (HHV-6) is increasingly recognized as an opportunistic and potentially life-threatening pathogen in recipients of allogeneic stem cell transplants (SCTs). METHODS To clarify the incidence and clinical relevance of active HHV-6 infection, serial titers of plasma HHV-6 DNA were determined for 50 allogeneic SCT recipients, using real-time polymerase chain reaction. RESULTS HHV-6 DNA was detected in plasma from 24 patients (48%). HHV-6 DNA was most frequently apparent approximately 14-27 days after transplantation. An increased risk of a positive result for HHV-6 DNA was associated with transplantation from an allelic-mismatch donor (P = .02) and administration of steroids (P = .04). Steroid use was associated with high HHV-6 DNA loads (P = .02). High HHV-6 DNA loads were correlated with delayed platelet engraftment (P = .04). Among patients who had positive results for HHV-6 DNA, the HHV-6 DNA load was higher in plasma from those who developed limbic encephalitis (n = 4) (P < .0001). CONCLUSIONS Active HHV-6 infection is not rare in SCT recipients. SCT from allelic-mismatch donors is associated with increased risk of active HHV-6 infection. Steroid therapy is associated with not only increased incidence of infection but also accelerated viral replication. Development of limbic encephalitis is associated with high HHV-6 DNA load.

Foscarnet against human herpesvirus (HHV)-6 reactivation after allo-SCT: breakthrough HHV-6 encephalitis following antiviral prophylaxis

High incidences of human herpesvirus (HHV)-6 encephalitis have recently been reported from several Japanese SCT centers. To evaluate the effect of low-dose foscarnet (PFA) in preventing HHV-6 infection among recipients of unrelated BM or cord blood (CB), we examined consecutive cohorts without prophylaxis against HHV-6 (Cohort 1, n=51) and with PFA prophylaxis (Cohort 2, PFA 50 mg/kg/day for 10 days after engraftment, n=67). Plasma real-time PCR assay was performed weekly. High-level reactivation defined as HHV-6 DNA⩾104 copies/mL by day 70 was the primary endpoint. No significant reduction of high-level reactivation was seen in Cohort 2 (19.4%) compared with Cohort 1 (33.8%, P=0.095). A trend was identified toward fewer high-level HHV-6 reactivations in Cohort 2 among recipients of unrelated BM (P=0.067), but no difference in incidence was observed among CB recipients (P=0.75). Breakthrough HHV-6 encephalitis occurred following PFA prophylaxis in three patients, and incidence of HHV-6 encephalitis did not differ between Cohort 1 (9.9%) and Cohort 2 (4.5%, P=0.24). In conclusion, 50 mg/kg/day of PFA does not effectively suppress HHV-6 reactivation and cannot prevent all cases of HHV-6 encephalitis. To effectively prevent HHV-6 encephalitis, alternative approaches based on the pathogenesis of HHV-6 encephalitis will probably be required.

Real-Time PCR Assay Compared to Nested PCR and Antigenemia Assays for Detecting Cytomegalovirus Reactivation in Adult T-Cell Leukemia-Lymphoma Patients

ABSTRACT We analyzed the efficiency of the quantitative real-time PCR assay for cytomegalovirus (CMV) reactivation in adult T-cell leukemia-lymphoma (ATL) patients and compared the results with those obtained with qualitative nested PCR and antigenemia assays. The viral load obtained by the real-time PCR assay closely paralleled the number of antigen-positive cells obtained with the antigenemia assay. Real-time PCR revealed that a large number of DNA copies could be present even in samples assessed as negative or low in antigen-positive cells (0 to 10 antigen-positive cells/50,000 cells) by antigenemia assay. CMV copy numbers did not differ between the negative and low-antigen-positive groups. When the input concentration for real-time PCR assay was 2,500 to 5,000 copies/ml, the positivity rate for the nested PCR assay was 47.3%, while the positivity rate was more than 90% at an input concentration of ≥50,000 copies/ml. Real-time PCR is more sensitive than the antigenemia and nested PCR assays. Moreover, real-time PCR was able to detect CMV reactivation earlier than the antigenemia and nested PCR assays through the use of longitudinal analysis in four ATL patients with CMV pneumonia. In longitudinal assessments, analysis of the results suggested that a cutoff level of 5,000 copies/ml might be used to initiate treatment. Real-time PCR is more suitable for monitoring CMV reactivation in ATL patients than the antigenemia and nested PCR assays. CMV viral loads of 5,000 copies/ml are proposed as the cutoff for initiating antiviral therapy in ATL patients.

Eosinophilia associated with adult T-cell leukemia: role of interleukin 5 and granulocyte-macrophage colony-stimulating factor.

To clarify the mechanism of eosinophilia in adult T‐cell leukemia (ATL), we studied three ATL patients having marked eosinophilia. Eosinophil‐predominant colony‐stimulating activity was detected in the serum of one patient and in the conditioned media (CM) from cultured ATL cells from two patients. Soluble interleukin 5 (IL‐5), but no interleukin 3 (IL‐3) and granulocyte‐macrophage colony‐stimulating factor (GM‐CSF), was detected in sera from all patients. On the other hand, GM‐CSF was produced in vitro by ATL cells from all cases, whereas detectable IL‐3 and IL‐5 was produced by cells from only one, suggesting that in the other two cases, the serum IL‐5 was produced by the normal reacting lymphocytes. The fact that no patient showed marked neutrophilia supports the possibility that IL‐5 may have a leading role in the development of eosinophilia, with GM‐CSF produced by ATL cells playing a complementary role. Am. J. Hematol. 59:242–245, 1998.

High incidence of cytomegalovirus, human herpesvirus-6, and Epstein–Barr virus reactivation in patients receiving cytotoxic chemotherapy for Adult T cell leukemia

The etiology of cytomegalovirus (CMV), human herpesvirus‐6 (HHV‐6), and Epstein–Barr virus (EBV) reactivation and the potential for complications following cytotoxic chemotherapy in the absence of allogeneic transplantation are not clearly understood. Patients with adult T cell leukemia (ATL) are susceptible to opportunistic infections. In this study, the incidence, kinetics and clinical significance of reactivation of CMV, HHV‐6, and EBV in ATL patients were investigated. Viral DNA in a total of 468 plasma samples from 34 patients was quantified using real‐time PCR. The probability of CMV, HHV‐6, and EBV reactivation by 100 days after the start of chemotherapy was 50.6%, 52.3%, and 21.6%, respectively. Although most CMV reactivations were self‐limited, plasma CMV DNA tended to persist or increase if the CMV DNA levels in plasma reached ≥104 copies/ml. CMV reactivation was negatively associated with survival, but the P‐value for this association was near the borderline of statistical significance (P = 0.052). One patient developed fatal interstitial pneumonia concomitant with peak CMV DNA accumulation (1.6 × 106 copies/ml plasma). Most HHV‐6 and EBV reactivations were self‐limited, and no disease resulting from HHV‐6 or EBV was confirmed. HHV‐6 and EBV reactivation were not associated with reduced survival (P = 0.35 and 0.11, respectively). These findings demonstrated that subclinical reactivation of CMV, HHV‐6, and EBV were common in ATL patients receiving chemotherapy. There were differences in the viral reactivation patterns among the three viruses. A CMV load ≥104 copies/ml plasma was indicative of subsequent exacerbation of CMV reactivation and developing serious clinical course. J. Med. Virol. 83:702–709, 2011.

Acute myeloblasts leukaemia without Philadelphia chromosome developing after interferon therapy for chronic myelocytic leukaemia with Philadelphia chromosome

Summary. We report a patient who developed Philadelphia chromosome negative acute myeloblastic leukaemia with trisomy 8 and trisomy 11 after receiving treatment with alkylating agents and interferon for chronic myelocytic leukaemia positive for Philadelphia chromosome. Leukaemic cells were positive for myeloperoxidase and expressed CD13, CD33 and DR; some expressed CD2, CD4 and CD34. The fluorescence in situ hybridization method revealed that bcr‐abl fusion genes were absent from > 90% of the bone marrow cells. The major bcr rearrangement was not detected by Southern blot analysis. We conclude that the leukaemic cells negative for Philadelphia chromosome may have developed as a result of treatment with alkylating agents and interferon in the present case.

Successful Induction of Long-Term Remission Using Rituximab in a Patient with Refractory Hairy Cell Leukemia-Japanese Variant

We report the case of a 76-year-old man with hairy cell leukemia (HCL)-Japanese variant who underwent rituximab therapy. HCL proved refractory to treatment with pentostatin and cladribine, and the number of hairy cells in the peripheral blood continued to increase after splenectomy.The patient was treated with rituximab (375 mg/m2 intravenously weekly for 4 cycles), and hairy cells disappeared from the peripheral blood on the day after the first administration. Complete remission continued for 18 months after treatment. Although they produce high response rates in typical HCL, nucleoside analogs are associated with an inferior clinical response in HCL-Japanese variant, and repetitive administration of these agents increases the risk of serious infections. This encouraging result suggests that rituximab therapy should be considered as salvage therapy for refractory HCL-Japanese variant.

Allogeneic bone marrow transplantation-related transmission of human T lymphotropic virus type I (HTLV-I)

We report here the first case report of bone marrow transplantation (BMT)-related transmission of human T lymphotropic virus type-I (HTLV-I). Antibodies against HTLV-I-associated antigens (anti-HTLV-I) were detected in the serum from the BMT recipient 12 days post BMT. IgG against gag core proteins (anti-p19 and anti-p24) appeared earlier than IgM against gag and env proteins (anti-p19, anti-p24 and anti-gp46) during seroconversion. The data presented here differs from blood transfusion-related seroconversion. This phenomenon may be due to the engraftment of anti-HTLV-I producing cells from the donor. Bone Marrow Transplantation (2000) 26, 1235–1237.

Hemolytic uremic syndrome following autologous peripheral blood stem cell transplantation in a patient with malignant lymphoma

Hemolytic uremic syndrome (HUS) has been reported in patients receiving bone marrow transplantation. However, only a few cases of HUS following autologous peripheral blood stem cell transplantation (PBSCT) have been reported. We present a case of HUS developing after autologous PBSCT in a 40-year-old man with non-Hodgkin’s lymphoma. It appears that the chemotherapeutic agents administered during the conditioning regimen for PBSCT may have played an important role in the development of HUS in our patient. In the present case, the combination therapy of vincristine, methylprednisolone, and ticlopidine hydrochloride was effective.

Clinicopathological Features of Adult T-cell Leukemia with CD30 Antigen Expression

Recently, several cases of adult T-cell leukemia (ATL) with CD30 antigen have been reported, but its clinical significance remains unknown. Accordingly, we studied CD30 antigen expression in ATL cases and documented the clinicopathological characteristics of these cases. Immunohistochemical and clinical characteristics were studied in 46 patients with malignant lymphoma or benign lesions of lymphoid tissue, who had antibodies against human T-cell leukemia virus type I (HTLV-I). Monoclonal integration of HTLV-I provirus was demonstrated in the tumor cells in 36 (ATL) of the 46 cases. CD30 antigen expression was evident in seven of these 36 cases (19.4%), however it was not seen in any of the ten cases lacking the integration of HTLV-I provirus. A comparison of ATL cases with and without CD30 antigen expression revealed significantly larger numbers of abnormal lymphocytes in the peripheral blood and lower serum calcium levels in ATL expressing CD30 antigen.