Objective To explore the clinical presentation,etiology of sepsis,common positions of in-fection and anti-infectious treatment of pediatric acute leukemia with septicemia resistance to carbapenem. Meth-ods A retrospective chart review of all pediatric acute leukemia with septicemia cases of Beijing Children 's Hospital from December 2011 to September 2015 were analyzed. All cases were selected based on the clinical presentation,at least one Gram-negative bacteria positive result of blood culture and were resistant to carbapen-em. The basic clinical characteristics and the results of blood culture and antimicrobial susceptibilities were ana-lyzed. Results All 45 cases with fever,among them 8 cases under went continued fever,The other 37 cases fe-ver days were ( 6. 1 ± 5. 2 ) d. Twenty-six cases had agranulocytosis. Agranulocytosis time from 2 to 79 days, mean days(15. 2 ± 16. 2)d. Significant difference of fever time between agranulocytosis team and non-agranulo-cytosis team was significant(P=0. 011). Twenty-three cases had infection positions among 45 cases. Lung,di-gestive tract,mouth and crissum were the common positions of infection. The quantum of blood culture samples were 711 parts. There were 162 parts resistant to carbapenems. The primary pathogens were pseudomonas aerugi-nosa,klebsiella pneumoniae, enterobacter cloacae and Escherichia coli. Among those 45 cases, 36 cases were cured,9 cases were ineffective treatment. Conclusion Pseudomonas aeruginosa, klebsiella pneumoniae, enter-robacter cloacae and Escherichia coli accounted for the most of G-bacteria infections resistant to carbapenem in our center. The incidence of septicemia was related to the level of granulocyte and duration of agranulocytosis.

Objective To investigate the epidemiology of fungemia and provide evidence for clinical therapy.Methods A retrospective survey was conducted with 42 cases of fungemia in our hospital from Jan 2002 to Jan 2011.Results Forty cases candida fungemia accounted for 95.2％ in 42 fugemia.The main pathogen agent was non-Candida albicans in candida fungemia,which were candida albicans(14.3％),candida parapsilosis (38.1％),candida glabrata (35.7 ％),candida tropicalis (2.4％).Eleven uneffecfive cases accounted for 26.2％.Multiple-factor analysis showed that neutropenia time ＞ 7 days,antibiotic using time ＞ 7 days and fungal infection history correlated with bad prognosis.Our study also showed that chemotherapy regiments including hormone、combining with other organs fungal infection and non-Candida albicans were risk factors of bad prognosis.Conclusion The main pathogen agent of fungimia is candida,especially non-Candida albicans.Neutropenia time ＞ 7 days,antibiotic using time ＞ 7 days and fungal infection history correlate with poor prognosis.

Objective To investigate the epidemiology of fungemia and provide evidence for clinical therapy.Methods A retrospective survey was done with the 42 cases of fungemia in our hospital.Results 42 cases of fungemia include 35 cases acute lymphoid leukemia,6 acute myloid leukemia.95.2％ of the fungemia pathogen agent was monilia.8 cases combined with bacterial septicemia,accounting for 19.0％.Drug sensitivity test showed that 2 cases were intermediary to Fluconazole,1 patient was resisdence to Amphotericin B but sensitive to Voriconazole,Itraconazole and fluorocytosine.The main risk factors of fungimia included using wide-spectrum antibiotic,neutophil less than 0.5 × 109/L,central venous indwelling catheter,age and the time of in hospital more than 15 days.Conclusion The effective measure to reduce fungemia morbitity is controlling risk factors.Timely and effectively antifungal therapy is also needed.

Objective:To construct the molecular transmission network of human immunodeficiency virus type 1 (HIV-1) epidemic strains in northern Zhejiang Province (Jiaxing City and Huzhou City) and to explore the HIV-1 transmission characteristics in this region.Methods:A total of 371 newly diagnosed human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) patients in Jiaxing City and Huzhou City in 2017 were included as study subjects, and the blood samples were collected and the basic demographic and epidemiological information were obtained. RNA in plasma was extracted, and the pol region gene sequence was amplified by reverse transcriptase polymerase chain reaction (RT-PCR) and nested polymerase chain reaction (PCR) to construct phylogenetic tree for identifying subtypes. The pairwise genetic distances were calculated, and the optimal threshold of genetic distance was selected, and finally the molecular transmission network was constructed. Chi-square test was used for statistical analysis. Results:The pol region gene sequences of 336 samples were successfully obtained, and 11 subtypes were detected, mainly including circulating recombinant form (CRF)07_BC (40.8%, 137/336) and CRF01_AE (31.2%, 105/336). Based on the 1.0% genetic distance threshold, the molecular transmission network of HIV-1 was plotted. A total of 38 transmission clusters (cluster sizes ranging from two to 28) including 119 patients were found, with males predominantly (82.4%, 98/119) and most of the patients aged over 40 (include 40) years old (52.9%, 63/119), mainly infected with CRF07_BC subtype (57.1%, 68/119) and CRF01_AE (24.4%, 29/119). The clustering rate of CRF07_BC (49.6%, 68/137) was significantly higher than that of CRF01_AE (27.6%, 29/105), the difference was statistically significant ( χ2=5.27, P=0.022). Two large clusters C1 (28 cases) and C2 (11 cases) were identified, the majority of which were men who have sex with men (17 cases and seven cases, respectively). High-risk cases generally sought sexual partners in local or nearby cities through mobile phone dating software, of which the infected sequences mostly had high homology with other economic developed regions (Guangdong Province, Beijing City and Hangzhou City, etc.). Conclusions:The HIV-1 subtypes are diverse in Jiaxing City and Huzhou City, mainly CRF07_BC and CRF01_AE. The HIV-1 transmission networks are complex, among which high-risk cases may be the key factor leading to the HIV-1 epidemic in the region. Therefore, it is urgent to deepen the transmission network monitoring and formulate timely precise intervention and prevention strategies.

Objective To understand the characteristics of distribution on HIV-1 subtypes and the transmission clusters in Yiwu in Zhejiang province.Methods A cross-sectional study of molecular epidemiology was carried out on newly reported H1V/AIDS cases in Yiwu.RNA was extracted from 168 plasma samples,followed by RT-PCR and nest-PCR for pol gene amplification,sequencing,phylogenetic tree construction used for analyzing the subtypes and transmission clusters.Mutations on drug resistance was analyzed by CPR 6.0 online tool.Results Subjects were mainly males (86.3％,145/168),with average age as (39.1 ± 13.4) years old and most of them were migrants (66.7％,112/168).The major routes of transmission included homosexual (51.2％,86/168) and heterosexual (48.8％,82/168) contacts.The rate of success for sequence acquisition was 89.9％ (151/168).The dominant subtypes showed as CRF01_AE (74,49.0％) and CRF07_BC (64,42.4％),followed by CRF08_BC (5,3.3％),CRF55_01B (3,2.0％),each case of subtype B,CRF45_cpx,CRF59_01B,CRF85_BC and URF (B/C).CRF45_cpx and CRF85_BC were discovered the first time in Zhejiang province.Twenty-six transmission clusters involving 65 cases were found,with the total clustered rate as 43.0％ (65/151),in which the CRF01_AE clustered rate appeared as 54.1％ (40/74),higher than that of CRF07_BC (21/64,32.8％).The average size of cluster was 2.5 cases/cluster,with average size of cluster in CRF01_AE patients infected through heterosexual transmission as the largest (3.5 cases/cluster).The prevalence of transmitted drug resistance was 4.6％ (7/151).Seven cases with surveillance drug resistant mutations (SDRM) were found,including 5 cases of M46L (3.3％),and one case of F77L or Y181C.Conclusion HIV genetic diversity and a variety of transmission clusters had been noticed in this study area (Yiwu).Programs on monitoring the subtypes and transmission clusters should be continued and strengthened.

Objective: To know the detection rate of hereditary thrombocytopenia (HT) in children with chronic thrombocytopenia and its clinical and laboratory characteristics for an early clinical identification and diagnosis of HT in future. Methods: Data of the children with thrombocytopenia, who had been treated in Beijing Children′s Hospital from April 2016 to May 2018 and whose present history lasted for more than 1 year and had poor response to immunotherapy were retrospectively collected.HT was screened in these patients by adopting next generation sequencing (NGS). Finally, clinical and laboratory characteristics of these children with HT were summarized and analyzed. Results: A total of 161 children with chronic thrombocytopenia were included.Forty-three cases (26.7%) were found to have gene mutations.The genetic rules of the mutant gene, the family verification and the clinical manifestations of the proband and some related laboratory tests were analyzed and 24 cases (14.9%) can be diagnosed as HT.Among the HT patients, the proportion of males and females was 159, and the median onset of age was 0.58 years, which was significantly lower than that of non-HT cases (the median onset of age was 4.36 years), and the difference was statistically significant (P<0.001); the proportion of mucosal hemorrhage and visceral hemorrhage (31.8% and 13.7%) of HT was significantly higher than non-HT cases (15.3% and 0.6%), and the difference was statistically significant (P<0.001). Fifty percent of (12/24 cases) cases of HT had positive family history; according to the ave-rage platelet volume and platelet morphology in peripheral blood smear, HT could be divided into small platelet HT, po-sitive platelet HT and large platelet HT.Some cases had well response to immunotherapy but seemed easy to relapse du-ring the withdrawal period, while the others responded poorly to therapy.Different clinical manifestations of HT suggest different pathogenesis, which can be divided into the related types of megakaryocyte differentiation defect, megakaryocyte maturation defect, platelet release defect and platelet survival time shortening. Conclusions The pathogenesis and cli-nical phenotype of HT was different.Some of them were effective for immunotherapy, which were easily confused with immune thrombocy-topenla(ITP). It is clinically necessary to perform NGS in children with thrombocytopenia at early onset, abnormal platelet morphology, prolonged disease course or severe mucosal/visceral hemorrhage, in order to recognize HT timely to avoid delay in diagnosis and poor prognosis.

OBJECTIVE To optimize the pr eparation technology of the baicalin lipid nano foam aerosol （BC-LN-FA）. METHODS Baicalin lipid nanoparticle （BC-LN）and BC-LN-FA were prepared by the thin film dispersion method and homogeneous emulsification method ，respectively，using baicalin （BC） as the model drug. The preparation technology was optimized by Box-Behnken design-response surface methodology using particle size and encapsulation efficiency （EE）as indexes ，with dosage ， emulsifier dosage ，co-emulsifier dosage and homogenization time as factors. The morphology ，particle size ，polymerdispersity index（PDI），EE，the viscosity ，the foam dissolution rate and in vitro transdermal release of BC-LN-FA were characterized. RESULTS The optimal technology included 25 mg BC ，40 mg emulsifier （mass ratio of stearic acid-soybean lecithin-glycerol was 1∶1∶1），30 mg co-emulsifier （mass ratio of octadecanol-lactic acid was 1∶1），homogenization time of 20 min. Results of 3 times of validation tests showed that particle size of prepared BC-LN-FA was （151.70±2.40）nm，EE was （68.62±1.16）％；the deviation of them from the predicted value （particle size of 150.80 nm，EE of 67.02％）were 0.60％ and 2.39％ respectively. The BC-LN-FA prepared by the optimal process was light yellow opalescence ，uniform in particle size and round-like in shape. The viscosity，the foam dissolution rate ，the content of BC and PDI were （122.92±5.09）mPa·s，（65.32±3.22）％，（7.01±0.12）％ and（0.199±0.006），respectively. At 48 h，the cumulative release rates of BC-LN-FA in phosphate buffer saline （PBS）at pH 7.4， 6.8，5.0 were（54.12±2.69）％，（57.85±4.25）％ and（59.47±1.83）％，respectively；those of free BC in PBS at pH 7.4 was only （15.04±1.43）％. CONCLUSIONS The optimized technology is stable and feasible. Prepared BC-LN-FA has a uniform particle size，high digestion rate and certain viscosity.

Objective:To investigate the related factors of the serum sickness morbidity in the treatment of children with acquired aplastic anemia (AA) by rabbit antithymosinglobulin (ATG), summarize the clinical characte-ristics of serum sickness and evaluate the influence of serum sickness on the prognosis of AA.Methods:The data of patients diagnosed as AA after treated with immunosuppressive therapy (IST) in Beijing Children′s Hospital, Capital Medical University, from March 2016 to December 2018 were collected, and the onset time, clinical manifestations, treatment, and prognosis of serum sickness were analyzed.Results:A total of 48 cases were enrolled, with the median age of 5 years and 5 months (ranging from 2 years and 1 month to 15 years and 6 months), and the proportion of male to female was 1.4∶1.0, 75.0% of the patients(36/48 cases) developed serum sickness.The median onset time was the 11 th day and 72.2% of the patients (26/48 cases) occurred from the 7 th to the 14 th day during IST.The 3 main clinical manifestations included arthralgia (63.9%, 23 cases), fever (52.7%, 19 cases) and rash (52.7%, 19 cases). There was no significant difference in peripheral blood leukocytes, neutrophils and lymphocytes between the patients with serum sickness and patients without serum sickness before IST and during serum sickness (all P>0.05). The incidence of serum sickness in children who received continuous glucocorticoid prophylaxis after IST (2/12 cases, 16.6%) was lower than that of those who did not (34/36 cases, 94.4%), and the difference was significant ( χ2=29.037, P<0.001). The symptoms of serum sickness improved after glucocorticoid therapy [Methylprednisolone 2-4 mg/(kg·d)]. Among 37 children who were followed up for 6 months or more after IST treatment, 25 patients had serum sickness and 12 patients did not have serum sickness.Nineteen patients with serum sickness and 10 patients without serum sickness were cured or markedly improved; 6 patients with serum sickness and 2 patients without serum sickness were not cured.No significant difference in the prognosis between 2 groups was observed ( P>0.05). Conclusion:Children with AA are prone to develop serum sickness after IST treatment.The peak period of incidence of serum sickness is the second week during IST, and the main clinical manifestations of serum sickness include arthralgia, fever, and rash.There is no correlation between the incidence of serum sickness and the blood routine test before IST and during serum sickness.The incidence of serum sickness can be reduced by giving glucocorticoid prophylaxis, and glucocorticoid is still effective after the onset of the serum sickness.There is no correlation between the morbidity of serum sickness and the prognosis of AA treated with IST.

A 6-year-old girl presented with recurrent skin rash at the initial stage, recent joint pain, and neutrophilia was found during a routine blood test. After a multidisciplinary case discussion, she was diagnosed with chronic neutrophil leukemia, and the symptoms were relieved after hydroxyurea and luxolitinib treatment. She received the allogeneic hematopoietic stem cell transplantation subsequently. At present, she is in stable condition and under follow-up. Chronic neutrophil leukemia is a rare disease, which rarely occurs in children. It is more difficult to diagnose in patients with skin rash as the first manifestation. The diagnosis and treatment of this case reflects the important role of multidisciplinary cooperation in the diagnosis and treatment of difficult and rare diseases.