Objective:To observe the efficacy of eculizumab in children with atypical hemolytic uremic syndrome.Methods:It was a single-center observational study. The clinical data of children diagnosed with atypical hemolytic uremic syndrome and treated with eculizumab in Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 2023 to May 2024 were retrospectively collected. Eculizumab was used at the conventional dose based on the children 's weight. Event-free survival (no death or end-stage renal disease) rate, complete remission rate and recurrence rate of thrombotic microangiopathy in children with atypical hemolytic uremic syndrome after eculizumab treatment were analyzed. The complete remission time of estimated glomerular filtration rate, hemoglobin, platelet, lactic dehydrogenase, urine routine and the adverse reactions during the treatment were observed. Whole exome sequencing was used to conduct genetic testing based on blood samples of the children and their parents.Results:There were 4 children enrolled in the study. Four children were all Han Chinese, including 3 males and 1 female. The median age of onset was 8 years (ranging from 7 to 10 years). Two patients had complement gene abnormalities, both of which were homozygous deletions of complement factor H-related 1 and complement factor H-related 3. All the patients were free of plasma exchange or perfusion after treatment with eculizumab, and the 6-month event-free survival rate and thrombotic microangiopathy complete remission rate were both 4/4. The complete remission time was 19 (14-28) days. The time for the complete recovery of platelets, lactate dehydrogenase, estimated glomerular filtration rate and hemoglobin in 4 children was 4 (1-5), 19 (14-28), 10 (5-14) and 29 (20-42) days, respectively. Except for 1 patient whose urine routine fluctuated between negative and weakly positive expression, the other 3 patients had normal urine routine. All the patients discontinued eculizumab. Two patients without gene mutations discontinued eculizumab after 7 doses, and there was no recurrence during the 1-year follow-up after drug withdrawal. Two patients with genetic abnormalities discontinued eculizumab after 26 weeks of treatment, and no recurrence was found during the 3-month follow-up after drug withdrawal. One patient developed rash approximately 7 days after receiving the third dose of eculizumab. The rash was relieved after anti-allergic treatment, and there was no recurrence after the continued use of eculizumab.Conclusion:Eculizumab is effective and safe in the treatment of children with atypical hemolytic uremic syndrome. Discontinuation of eculizumab can be considered in patients without gene mutations when their condition is stable, but close monitoring and follow-up are needed after drug withdrawal.

Objective:To observe the efficacy of eculizumab in children with atypical hemolytic uremic syndrome.Methods:It was a single-center observational study. The clinical data of children diagnosed with atypical hemolytic uremic syndrome and treated with eculizumab in Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 2023 to May 2024 were retrospectively collected. Eculizumab was used at the conventional dose based on the children 's weight. Event-free survival (no death or end-stage renal disease) rate, complete remission rate and recurrence rate of thrombotic microangiopathy in children with atypical hemolytic uremic syndrome after eculizumab treatment were analyzed. The complete remission time of estimated glomerular filtration rate, hemoglobin, platelet, lactic dehydrogenase, urine routine and the adverse reactions during the treatment were observed. Whole exome sequencing was used to conduct genetic testing based on blood samples of the children and their parents.Results:There were 4 children enrolled in the study. Four children were all Han Chinese, including 3 males and 1 female. The median age of onset was 8 years (ranging from 7 to 10 years). Two patients had complement gene abnormalities, both of which were homozygous deletions of complement factor H-related 1 and complement factor H-related 3. All the patients were free of plasma exchange or perfusion after treatment with eculizumab, and the 6-month event-free survival rate and thrombotic microangiopathy complete remission rate were both 4/4. The complete remission time was 19 (14-28) days. The time for the complete recovery of platelets, lactate dehydrogenase, estimated glomerular filtration rate and hemoglobin in 4 children was 4 (1-5), 19 (14-28), 10 (5-14) and 29 (20-42) days, respectively. Except for 1 patient whose urine routine fluctuated between negative and weakly positive expression, the other 3 patients had normal urine routine. All the patients discontinued eculizumab. Two patients without gene mutations discontinued eculizumab after 7 doses, and there was no recurrence during the 1-year follow-up after drug withdrawal. Two patients with genetic abnormalities discontinued eculizumab after 26 weeks of treatment, and no recurrence was found during the 3-month follow-up after drug withdrawal. One patient developed rash approximately 7 days after receiving the third dose of eculizumab. The rash was relieved after anti-allergic treatment, and there was no recurrence after the continued use of eculizumab.Conclusion:Eculizumab is effective and safe in the treatment of children with atypical hemolytic uremic syndrome. Discontinuation of eculizumab can be considered in patients without gene mutations when their condition is stable, but close monitoring and follow-up are needed after drug withdrawal.

Objective:To investigate the role of the NOD-like receptor thermal protein domain associated protein 3(NLRP3)inflammasome and its downstream interleukin(IL)-1β, IL-6, and IL-18 in the pathogenesis of antineutrophil cytoplasmic antibody-associated vasculitis(AAV) in children.Methods:A retrospective study was conducted.Specifically, the localization and expression of the NLRP3 inflammasome in renal tissues of 22 children who were diagnosed with primary AAV and underwent renal biopsy in the Department of Pediatric Nephrology and Rheumatology, the First Affiliated Hospital of Sun Yat-Sen University from September 2003 to September 2020 were detected by the immunohistochemical method.The IL-1β, IL-6 and IL-18 levels in serum and urine were measured by enzyme-linked immunosorbent assay.The measurement data conforming to normal distribution were compared by the t test between two groups and by the single factor ANOVA test among multiple groups.The measurement data that did not conform to normal distribution were compared by the Wilcoxon signed rank sum test.Classification variables were examined by the χ2 test. Pearson correlation coefficient or Spearman rank correlation coefficient were used to analyze the correlation among variables. Results:NLRP3 was widely expressed in the tubulointerstitium, and the expression level in the active group was higher than that in the control group, the semi-quantitative scores of NLRP3 in the renal tubule and glomeruli in the active group were higher than those in the control group ( F=0.859, 8.320, all P<0.05). In the active group, the semi-quantitative score of NLRP3 in the renal tubule was higher than that in the glomeruli( F=3.517, P<0.05). The semi-quantitative score of NLRP3 in the renal tubule was positively correlated with the pediatric vasculitis activity score at renal biopsy ( r=0.471, P=0.027)and negatively correlated with the estimated glomerular filtration rate at renal biopsy ( r=-0.548, P=0.008)in the active group.The serum IL-1β, serum IL-18 and urinary IL-6 levels in the active group were higher than those in the remission group and the control group ( F=16.449, 16.449, 0.637, 29.891, 27.612, 7.464, all P<0.05). The serum IL-18 level in the remission group was higher than that in the control group( F=18.671, P<0.05). In the active group, a positive correlation was found between the serum IL-1β level and the semi-quantitative score of NLRP3 in the renal tubule( r=0.805, P=0.002), between the serum IL-6 level and the C-reactive protein level at renal biopsy ( r=0.728, P=0.017), and between the urinary IL-6 level and the crescent proportion at renal biopsy ( r=0.677, P=0.032). The serum IL-18 level in the active group was positively correlated with the semi-quantitative score of NLRP3 in the renal tubule, pediatric vasculitis activity score and glomerular sclerosis proportion at renal biopsy, and negatively correlated with the estimated glomerular filtration rate at renal biopsy ( r=0.644, 0.612, 0.695, -0.577, all P<0.05). The urinary IL-18 level was positively correlated with the complement C 4 level at renal biopsy ( r=0.855, P<0.05). Conclusions:The NLRP3 inflammasome and its downstream IL-1β, IL-6, and IL-18 may be involved in the pathogenesis and progression of AAV, and can be used as one of the reference indicators for disease activity assessment.

Objective To compare the CT changes in lungs among mechanically-ventilated dogs before and after a single hyperbaric oxygen exposure,and investigate the effects of HBO on lungs.Methods Forty healthy adult dogs were randomly divided into 4 groups:the hyperbaric oxygen (HBO) group,the normabaric oxygen (NBO) group,the hyperbaric air group and the normabaric air group.All the dogs were mechanically ventilated and CT scan on lungs were taken before and after the session to compare the CT value by Picture Archiving and Communication System on different lung parts.Results There was no significant difference between all the groups of apical and median fields of lung CT values (P ＞ 0.05).In HBO and NBO groups,deficiency of pulmonary aeration developed preferentially in caudal lung fields.Compared with the NBO group,the changes of HBO group were more dramatic.There were significant differences in CT values between HBO and NBO groups(P ＜0.05).Conclusions Compared with NBO,ventilating at 0.2 MPa caused much more significant deficient aerations of the lungs.

Objective To compare the CT changes in lungs among mechanically-ventilated dogs before and after a single hyperbaric oxygen exposure,and investigate the effects of HBO on lungs.Methods Forty healthy adult dogs were randomly divided into 4 groups:the hyperbaric oxygen (HBO) group,the normabaric oxygen (NBO) group,the hyperbaric air group and the normabaric air group.All the dogs were mechanically ventilated and CT scan on lungs were taken before and after the session to compare the CT value by Picture Archiving and Communication System on different lung parts.Results There was no significant difference between all the groups of apical and median fields of lung CT values (P ＞ 0.05).In HBO and NBO groups,deficiency of pulmonary aeration developed preferentially in caudal lung fields.Compared with the NBO group,the changes of HBO group were more dramatic.There were significant differences in CT values between HBO and NBO groups(P ＜0.05).Conclusions Compared with NBO,ventilating at 0.2 MPa caused much more significant deficient aerations of the lungs.