[Nosocomial septicemia in the early stage after stem cell transplantation in children with major ß-thalassemia].

OBJECTIVE: To explore the clinical characteristics of nosocomial septicemia in the early stage after hematopoietic stem cell transplantation (HSCT) in children with major ß-thalassemia. METHODS: The clinical data were retrospectively analyzed of 55 consecutive children with major ß-thalassemia who developed septicemia early after HSCT between January, 2011 and June, 2016. RESULTS: Among the total of 416 consecutive children with major ß-thalassemia undergoing allogeneic HSCT, the incidence of nosocomial infection early after transplantation was 77.16% (321/416), and 55 (17.13%) children showed positive findings in blood culture test. The infections occurred most commonly in the oral cavity (65.5%), followed by the respiratory tract, intestinal tract and skin. Gram-negative bacteria, including Escherichia coli (27.3%), Klebsiella pneumoniae (21.8%) and Pseudomonas aeruginosa (9.1%), were the most common causes of infections. Fungal (Candida tropicalis) infection caused septicemia in 1 case. Of all the pathogens, extended-spectrum ß-lactamase (ESBL)-producing bacteria were found in 6 cases, methicillin-resistant Staphylococcus aureus (MRSA) in 2 cases, and multidrug-resistant (MDR) bacteria in 2 cases. CONCLUSION: Gram-negative bacteria are the major pathogens causing septicemia in children early after HSCT for major ß-thalassemia, and the bacteria show a high level of drug resistance. Adequate preventive use of antibiotics and care of the oral cavity, the respiratory tract, and the perianal region following the transplantation are important measures to control nosoconial infection in these children.

[Outcome of childhood high-risk acute lymphoblastic leukemia treated with the ALL-BFM 95 protocol].

OBJECTIVE: To evaluate the effectiveness and the practicability of the Acute Lymphoblastic Leukemia Berlin-Frankfurt-Münster 95 (ALL-BFM 95) protocol in treating childhood high-risk acute lymphoblastic leukemia (HR-ALL). METHODS: A retrospective analysis of 47 children with newly diagnosed HR-ALL between July 2003 and August 2013 was performed. These children were treated by the ALL-BFM 95 protocol. Survival was evaluated by Kaplan Meier analysis and Log-Rank test. RESULTS: Relapse-related death occurred in 12 of 47 patients (26%), and 5 of 47 patients (11%) were treatment-related mortality. Five-year probability of event-free-survival (pEFS) was 62%. Children with hematopoietic stem cell transplantation (HSCT) after chemotherapy achieved significantly better pEFS than those with chemotherapy alone (77% vs 52%; P=0.035). The patients who were only poor responders to prednisone had a better outcome (5-year pEFS 80%) than the Days 15 and 33 bone marrow M3 subgroups (5-year pEFS 60% and 0 respectively). CONCLUSIONS: ALL-BFM 95 protocol can improve the outcome of children with high-risk ALL. The major cause of death is attributed to relapse. Chemotherapy plus HSCT can produce a better outcome than chemotherapy alone. The Days 15 and 33 bone marrow M3 subgroups have a poor prognosis.

[Analysis of the risk factors for hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation for beta-thalassemia in children].

OBJECTIVE: To analyze the risk factors of hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation for beta-thalassemia in children. METHODS: The clinical records of 30 children with beta-thalassemia undergoing allogeneic hematopoietic stem cell transplantation between December, 2008 and November, 2009 were analyzed. RESULTS: Hemorrhagic cystitis occurred in 8 of the 33 patients with an incidence of 24.24%, including 1 with grade I, 6 with grade II and 1 with grade III hemorrhagic cystitis. The median time of hemorrhagic cystitis onset was 22.9 days (range 6-35 days) and the median duration was 11.9 days(range 3-27 days). Univariate analysis indicated that the different types of transplantation and acute graft-versus-host disease affect the occurrence of hemorrhagic cystitis. The children with Allo-PBSCT had higher incidence than those receiving Allo-PBSCT+Allo-UBT and Allo-BMT (P<0.05). The children at an age >or=6 years had obviously higher incidence of hemorrhagic cystitis than those at younger ages. CONCLUSION: Age is the major factor that affects the occurrence of hemorrhagic cystitis in children undergoing allogeneic hematopoietic stem cell transplantation for beta-thalassemia.

Mixed hematopoietic chimerism for preventing graft-versus-host disease in mice receiving rat bone marrow transplantation.

OBJECTIVE: To find a method for preventing graft-versus-host disease (GVHD) in BALB/c mice receiving rat bone marrow transplantation. METHODS: Firstly 12 SD rats were conditioned with 5.0 Gy sublethal total body irradiation(TBI), followed by infusion of 8 x 10(7) bone marrow cells from 28 BALB/c mice within 4 h and intraperitoneal administration of 100 mg/kg cyclophosphamide (Cy) 2 d later, for the purpose of inducing chimeric SD rats with specific immunological tolerance. Secondly, 24 BALB/c mice were exposed to 9.0 Gy lethal TBI and divided randomly into 3 equal groups designated respectively as groups A, B and C. Mice in group A were injected with 4 x 10(7) bone marrow cells from 4 normal rats, and mice in group B were injected with 4 x 10(7) bone marrow cells and 2 x 10(7) spleen cells from 4 normal rats, while those in group C were given 4 x 10(7) bone marrow cells and 2 x 10(7) spleen cells from 6 chimeric rats. The mice were then observed for 150 d for GVHD. RESULTS: In the second procedure, 2 mice in group A failed to survive due to infection and radiation injury respectively, and none of the rest mice presented signs of GVHD. The mice in group B all developed GVHD of varied degrees with symptoms as wasting, diarrhea, fur loss, arched body posture, and even bloody stool, and all died within 5 to 15 d with an average survival of 10.0 d (95% confidence interval 8,12). Pathological examination of the liver and intestinal tissues revealed inflammatory lymphocyte infiltration and necrosis. The majority of the mice in group C, in contrast, survived for more than 150 d with only two died on the postoperative days 18 and 31 respectively. The survival time of group B was significantly shorter than that of the other two groups. CONCLUSION: Donor/recipient chimerism may help prevent GVHD in xenogeneic bone marrow transplantation.