A Bivalent Inactivated Vaccine Prevents Enterovirus 71 and Coxsackievirus A16 Infections in the Mongolian Gerbil

Hand-foot-and-mouth disease (HFMD) is a viral infectious disease that occurs in children under 5 years of age. Its main causes are coxsackievirus (CV) and enterovirus (EV). Since there are no efficient therapeutics for HFMD, vaccines are effective in preventing the disease. To develop broad coverage against CV and EV, the development of a bivalent vaccine form is needed. The Mongolian gerbil is an efficient and suitable animal model of EV71 C4a and CVA16 infection used to investigate vaccine efficacy following direct immunization. In this study, Mongolian gerbils were immunized with a bivalent inactivated EV71 C4a and inactivated CVA16 vaccine to test their effectiveness against viral infection. Bivalent vaccine immunization resulted in increased Ag-specific IgG antibody production; specifically, EV71 C4a-specific IgG was increased with medium and high doses and CVA16-specific IgG was increased with all doses of immunization. When gene expression of T cell-biased cytokines was analysed, Th1, Th2, and Th17 responses were found to be highly activated in the high-dose immunization group. Moreover, bivalent vaccine immunization mitigated paralytic signs and increased the survival rate following lethal viral challenges. When the viral RNA content was determined from various organs, all three doses of bivalent vaccine immunization were found to significantly decrease viral amplification. Upon histologic examination, EV71 C4a and CVA16 induced tissue damage to the heart and muscle. However, bivalent vaccine immunization alleviated this in a dose-dependent manner. These results suggest that the bivalent inactivated EV71 C4a/CVA16 vaccine could be a safe and effective candidate HFMD vaccine.

Clinical Characteristics and Treatment Outcome of the Desmoplastic Small Round Cell Tumor / 임상소아혈액종양

BACKGROUND: Desmoplastic small round cell tumor (DSRCT) is an aggressive malignancy with a poor prognosis. DSRCT is a rare disease, and therefore a standard treatment regimen has not been established. In this study, we reviewed the clinical characteristics and treatment outcomes of pediatric DSRCT patients.METHODS: We retrospectively reviewed the medical records of 5 DSRCT patients (2 boys, 3 girls) that were diagnosed and treated with DSRCT at Seoul National University Children's Hospital from January 1999 to January 2015.RESULTS: The median age at diagnosis was 11 years 5months (range 4 years 10 months-17 years 2 months). The most frequent symptoms were abdominal pain (60%). The primary sites were gastrointestinal tract, bladder, and omentum, and the involved sites were the liver, gastrointestinal tract, bladder and bone. Three patients had multiple metastases at diagnosis. Two patients underwent upfront surgical excision of primary tumor, and the remaining 3 patients received neo-adjuvant chemotherapy after the diagnosis was confirmed by using needle biopsy. Combination chemotherapy was administered to all patients in addition to radiotherapy (median dose 45 Gy, range 17.5-54 Gy). Four patients showed disease progression or relapse, resulting in a 20% overall survival rate. At the time of analysis, one patient is alive. She had localized disease at the time of diagnosis and were treated with upfront surgery, chemotherapy, and high-dose chemotherapy with autologous stem cell transplantation and radiotherapy.CONCLUSION: Patients with DSRCT have a poor prognosis, even after multimodal treatment. Further studies are needed to determine the prognostic factors of DSRCT.

A Case of Long-term Survival with Autologous Recovery after Double Cord Blood Transplantation for Juvenile Myelomonocytic Leukemia / 임상소아혈액종양

A 1.1 year old boy was admitted to the Seoul National University Children's Hospital because of incidental findings of hepatosplenomegaly, skin lesion and multiple intra- abdominal lymphadenopathies. Anemia and thrombocytopenia were found based on the initial complete blood count (CBC) measurements. Because of bicytopenia and hepatosplenomegaly, bone marrow examination was performed which revealed hypercellular marrow with increased monocytes and granulopoiesis. The hemoglobin F level was high for his age, and monocyte production was increased. The patient was diagnosed with juvenile myelomonocytic leukemia at the age of 1.2 years. Chemotherapy with cytarabine, etoposide, vincristine, and isotretinoin was initiated. After 6 cycles of chemotherapy, the CBC normalized. He underwent double cord blood transplantation (dCBT), but chimerism studies showed autologous recovery. However, he did not show relapse during the 5 years post-transplant during which he received isotretinoin. He is surviving disease-free 9 years after dCBT.

Characteristics of Bronchopulmonary Dysplasia in Very Low Birth Weight Infants according to the Timing of Dexamethasone Administration / 대한주산의학회잡지

PURPOSE: Corticosteroids has been used for treatment and prophylaxis of bronchopulmonary dysplasia (BPD) in preterm infants. However, administration of corticosteroids could be delayed due to its potential harmful effects on neurodevelopment. The aim of this study was to evaluate the adequate dexamethasone administration timing in very low birth weight infants. METHODS: Medical records of 56 VLBW infants who were admitted to neonatal intensive care unit of Seoul National University Children's Hospital and Seoul National University Bundang Hospital between January 2008 and September 2014 were collected retrospectively. Study population were divided into early administration group (dexamethasone administration before 4 weeks of postnatal days) and late administration group (after 4 weeks) and respiratory morbidities were compared between groups. RESULTS: There were no significant differences in clinical characteristics between early administration group (n=30) and late administration group (n=26). Respiratory severity score and oxygen needs at 7 days after birth and before administering dexamethasone were comparable. Extubation was done earlier postnatal days in early administration group. Incidence of severe BPD was higher in the late administration group. There was no significant difference in diagnosed with cerebral palsy (CP) at 12 months of corrected age. When adjusting for multiple risk factors, administration of dexamethasone 4 weeks after birth and severe of BPD showed a significant association (adjusted OR 17.14 [1.29-227.52], P=0.031). CONCLUSION: Administration of dexamethasone in order to minimize ventilator care and to reduce severe BPD might be done between 1 week and 4 weeks after birth in very low birth weight infants.

Clinical Characteristics and Treatment Outcome of the Desmoplastic Small Round Cell Tumor / 임상소아혈액종양

BACKGROUND: Desmoplastic small round cell tumor (DSRCT) is an aggressive malignancy with a poor prognosis. DSRCT is a rare disease, and therefore a standard treatment regimen has not been established. In this study, we reviewed the clinical characteristics and treatment outcomes of pediatric DSRCT patients. METHODS: We retrospectively reviewed the medical records of 5 DSRCT patients (2 boys, 3 girls) that were diagnosed and treated with DSRCT at Seoul National University Children's Hospital from January 1999 to January 2015. RESULTS: The median age at diagnosis was 11 years 5months (range 4 years 10 months-17 years 2 months). The most frequent symptoms were abdominal pain (60%). The primary sites were gastrointestinal tract, bladder, and omentum, and the involved sites were the liver, gastrointestinal tract, bladder and bone. Three patients had multiple metastases at diagnosis. Two patients underwent upfront surgical excision of primary tumor, and the remaining 3 patients received neo-adjuvant chemotherapy after the diagnosis was confirmed by using needle biopsy. Combination chemotherapy was administered to all patients in addition to radiotherapy (median dose 45 Gy, range 17.5-54 Gy). Four patients showed disease progression or relapse, resulting in a 20% overall survival rate. At the time of analysis, one patient is alive. She had localized disease at the time of diagnosis and were treated with upfront surgery, chemotherapy, and high-dose chemotherapy with autologous stem cell transplantation and radiotherapy. CONCLUSION: Patients with DSRCT have a poor prognosis, even after multimodal treatment. Further studies are needed to determine the prognostic factors of DSRCT.

A Case of Long-term Survival with Autologous Recovery after Double Cord Blood Transplantation for Juvenile Myelomonocytic Leukemia / 임상소아혈액종양

A 1.1 year old boy was admitted to the Seoul National University Children's Hospital because of incidental findings of hepatosplenomegaly, skin lesion and multiple intra- abdominal lymphadenopathies. Anemia and thrombocytopenia were found based on the initial complete blood count (CBC) measurements. Because of bicytopenia and hepatosplenomegaly, bone marrow examination was performed which revealed hypercellular marrow with increased monocytes and granulopoiesis. The hemoglobin F level was high for his age, and monocyte production was increased. The patient was diagnosed with juvenile myelomonocytic leukemia at the age of 1.2 years. Chemotherapy with cytarabine, etoposide, vincristine, and isotretinoin was initiated. After 6 cycles of chemotherapy, the CBC normalized. He underwent double cord blood transplantation (dCBT), but chimerism studies showed autologous recovery. However, he did not show relapse during the 5 years post-transplant during which he received isotretinoin. He is surviving disease-free 9 years after dCBT.

Severe Anemia Due to Parvovirus Infection Following Treatment with Rituximab in a Pediatric Kidney Transplant Recipient: Anemia after Treatment of Rituximab in Kidney Recipient Patient

Rituximab (RTX), a monoclonal antibody against the B-cell marker CD20, is commonly used as a treatment for antibody-mediated diseases or B-lymphocyte-mediated diseases. Destruction of B cells may reverse the disease course in many conditions; however, patients who are treated with RTX cannot respond appropriately to de novo infection due to lack of B lymphocytes. Here, we report one such case. A 7-year-old renal allograft recipient presented with severe anemia due to parvovirus infection after RTX treatment. The patient had focal segmental glomerulosclerosis and had received cadaveric kidney transplantation 6 months previously. She was treated with high-dose steroid for acute rejection and RTX for Epstein Barr Virus infection 3 months previously. At presentation, her hemoglobin level was 5.4 g/dL and leukocyte and platelet counts were normal. She had microcytic normochromic anemia and high viral load of parvovirus B19(70,578 copies/mL). Intravenous immunoglobulin (200 mg/kg.d) treatment controlled the progression of anemia and parvovirus infection. De novo parvovirus infection during the B lymphocyte-depletion period may have precipitated the severe anemia in this case. Close monitoring of infection is required after RTX therapy.