Objective:To evaluate the efficacy and safety of rituximab (RTX) in children with steroid resistant nephrotic syndrome (SRNS).Methods:The was a retrospective observational study. A retrospective analysis was conducted on the clinical data of 14 children with SRNS who received RTX treatment in the Department of Nephrology, Children's Hospital Affiliated to Capital Institute of Pediatrics from July 2021 to August 2023. The changes in urinary protein content, renal function, serum albumin, immunoglobulin and other indicators before and after RTX medication were compared to evaluate the clinical efficacy and safety of RTX treatment for SRNS.Results:A total of 14 children with SRNS were selected for this study, with a male to female ratio of 6:8. The age of onset of kidney disease was (4.36±3.12) years, and 8 of them underwent kidney biopsy. Among them, 6 cases showed focal segmental glomerulosclerosis in renal pathology, and 2 cases showed minimal change disease. The age of 14 children who first used RTX was (8.45±3.98) years old, with a dose of 375 mg/m 2 and a maximum dose of 500 mg. The number of children who had used 2, 3, 4, and 5 doses of RTX was 6, 6, 1, and 1, respectively. RTX was administered orally with compound sulfamethoxazole to prevent infection. Glucocorticoids and immunosuppressants were discontinued 4.0(2.5, 6.5) months after the first dose of RTX. The median follow-up time was 10.5(6.0, 18.3) months. By the end of the 3-month, 6-month, and follow-up endpoints, the complete remission rates of kidney disease in the children were 100.0%(14/14), 85.7%(12/14), and 64.3%(9/14), respectively. Five children experienced kidney disease recurrence. Compared with before the first dose of RTX treatment, the serum albumin and height significantly increased, while body mass index significantly decreased at the end of follow-up (all P<0.05). There was no statistically significant difference in urinary protein content, renal function, and IgG (all P>0.05). During the RTX treatment, all 14 children did not experience any infusion reaction, and there were no serious infections during follow-up. One case was diagnosed with hypogammaglobulinemia. Conclusions:RTX can improve the remission rate and recurrence rate of SRNS children, reduce the dosage of glucocorticoids and related drug untoward reaction, significantly improve patient height and BMI, with minimal side effects. Especially for SRNS patients who cannot be relieved by the combination of glucocorticoids and immunosuppressants, RTX may be considered.

Objective:To analyze the clinical characteristics of renal abscess in children and provide suggestions for early diagnosis and treatment.Methods:The clinical data including general information, laboratory data, imaging results, treatment and prognosis of 20 pediatric patients with renal abscess admitted to the Department of Nephrology, Capital Center for Children's Health Capital Medical University were analyzed retrospectively.Results:A total of 8 males and 12 females were enrolled. The age of onset was 3.0 (0.8, 9.0) years. All cases had fever. Six cases presented with abdominal pain, 6 cases had poor appetite, 5 cases had vomiting and 5 cases urinary tract irritation symptoms. Laboratory data showed elevated white blood cells 20.4 (17.4,26.3)×10 9/L, C-reactive protein 126 (77, 154)mg/L, erythrocyte sedimentation rate 60 (41,73) mm/1 h in 20 cases and procalcitonin 4.7 (1.2,33.5)μg/L in 10 cases. Totally 18 cases had pyuria. Urine culture was positive in 8 cases. Enterococcus faecium and Pseudomonas aeruginosa was detected in 2 cases. Klebsiella pneumoniae was found in 1 case after performing blood culture. Renal abscess was confirmed in all cases by doing contrast-enhanced CT scan, while only 9 cases with abscesses were identified by using renal ultrasound. There were 14 cases with renal abscess formation confirmed at onset by performing magnetic resonance imaging. Nine cases were accompanied with congenital anomalies of the kidney and urinary tract. All cases received conservative medical treatment. Intravenous broad-spectrum antibiotics were administered for 23 (14, 39) d initially, while the medication in 11 cases were upgraded to meropenem or imipenem. Oral antibiotics were continued for 23 (14, 28) d after discharge in all cases. Within 1 year of follow-up, except for 1 case of recurrence, the others had a favorable prognosis. Conclusions:Renal abscess should be suspected for children presenting with unexplained fever, vomiting, abdominal pain, elevated white blood cell count, C-reactive protein, erythrocyte sedimentation rate and pyuria. Ultrasonography is suitable for screening and follow-up, while CT or magnetic resonance imaging can be used to confirm the diagnosis. Conservative management with broad-spectrum antibiotics is effective and can be considered the first-line therapy for pediatric renal abscess.

Renal tubular acidosis（RTA）in children is mainly primary，with a low incidence rate and often an insidious onset. It exhibits strong clinical heterogeneity，and the related complications include growth retardation，abnormal bone metabolism，and renal dysfunction，which seriously affect the life quality of children. Currently，clinical attention to RTA remains insufficient，and its genetic mechanisms have not been fully clarified. The metabolic control rate and patient compliance need to be improved. This article reviews important research advances in the field of primary RTA，summarizes progress in classification，etiology，diagnostic and therapeutic strategies，prognosis and long-term disease management. It emphasizes that the precise diagnosis and treatment of children with primary RTA require the integration of molecular genetic technologies，individualized treatment regimens，and long-term monitoring and follow-up. In the future，efforts should focus on enhancing epidemiological studies and establishing evidence-based guidelines，further elucidating the pathogenesis of RTA，developing better-tolerated medications suitable for long-term use，and advancing parallel strategies for the prevention and management of primary RTA.

Objective To investigate serum β2-MG, sCHE, and PSGL-1 expression in patients with esophageal cancer and their relationship to lung infection after mediastinoscopy. Methods A total of 118 patients with esophageal cancer were selected and divided into infected and uninfected groups according to whether they developed lung infection after surgery. An automatic microbiological identification system was used to detect the pathogenic bacteria of lung infection. ELISA was used to detect the levels of β2-MG, sCHE, and PSGL-1. Multivariate logistic regression was used to analyze the influencing factors of postoperative lung infection in patients with esophageal cancer. ROC curves were plotted to analyze the assessment value of serum β2-MG, sCHE, and PSGL-1 on postoperative lung infection. Results Fifty-two strains of bacteria were isolated from the sputum of 38 patients with postoperative lung infections, and these included 35 (67.31%) Gram-negative, 14 (26.92%) Gram-positive, and 3 (5.77%) fungal strains. The difference in long-term smoking history between the infected and uninfected groups was statistically significant (P<0.05). Serum β2-MG and PSGL-1 levels were significantly higher and sCHE levels were significantly lower in the infected group than in the uninfected group (P<0.05). Serum β2-MG and PSGL-1 levels were sequentially higher (P<0.05) and sCHE levels were sequentially lower (P<0.05) in the mild, moderate, and severe lung infection groups. Long-term smoking history, β2-MG, and PSGL-1 were risk factors affecting postoperative lung infection in patients with esophageal cancer (P<0.05), and sCHE was a protective factor (P<0.05). The AUCs of serum β2-MG, sCHE, and PSGL-1 for assessing postoperative lung infections were 0.807, 0.845, and 0.800, respectively, and the AUC of the three combined factors for assessing postoperative lung infections was 0.954, which was superior to that assessed individually (Z_{combination vs. β2-MG}=2.576, Z_{combination vs. sCHE}=2.623, Z_{combination vs. PSGL-1}=2.574, all P<0.05). Conclusion The serum levels of β2-MG and PSGL-1 increase and the sCHE level decreases in patients with esophageal cancer and postoperative pulmonary infection, which are also related with lung infection. Combined testing can improve the evaluation value of postoperative pulmonary infection in patients.

Objective:To explore the diagnostic value and clinical application of metagenomic next-generation sequencing (mNGS) technology in pediatric urinary tract infections (UTI).Methods:In this retrospective study, the clinical data of children with UTI admitted to the Department of Nephrology, Children′s Hospital, Capital Institute of Pediatrics, from March 2023 to March 2024 were collected.The positive detection rates, timeliness, and consistency of mNGS technology were compared with those of urine culture.Measurement data were subject to test of normality.The independent sample t test, Chi-square test or Fisher′s exact probability test were used for comparison between groups. Results:A total of 193 patients were included.The positive detection rate of urine culture was 36.3% (70/193).Among 42 patients who underwent mNGS testing, 37 cases (88.1%) tested positive.The positive detection rate of mNGS was significantly higher than that of urine culture ( χ2=37.357, P<0.001).It took significantly less time to report mNGS results than to report urine culture results ( Z=3.524, P<0.001).In the 42 cases that underwent mNGS testing, 5 cases (11.9%) were negative for urine pathogens by both methods, and 21 cases (50.0%) were positive by mNGS but negative by urine culture.Among the remaining 16 cases (38.1%) positive by both mNGS and urine culture, 14 cases (33.3%) achieved fully matching results, 1 case (2.4%) was fully mismatched, and 1 case (2.4%) was partially matched.Comparison of the positive detection rate and the duration of anti-infective treatment prior to specimen collection between urine culture and mNGS showed that the median durations for urine culture and mNGS positivity were 5 and 20 days, and the difference was statistically significant ( χ2=0.537, P<0.001). Conclusions:mNGS technology has high sensitivity for diagnosing pathogens in pediatric UTI.Compared with urine culture, mNGS provides good consistency and significantly shortens the detection time.The positive detection rate is less affected by antimicrobial treatment.For children with UTI, especially those who have failed empirical anti-infective treatment and whose pathogen cannot be identified by urine culture, mNGS testing is recommended as early as possible.

Objective:To explore the diagnostic value and clinical application of metagenomic next-generation sequencing (mNGS) technology in pediatric urinary tract infections (UTI).Methods:In this retrospective study, the clinical data of children with UTI admitted to the Department of Nephrology, Children′s Hospital, Capital Institute of Pediatrics, from March 2023 to March 2024 were collected.The positive detection rates, timeliness, and consistency of mNGS technology were compared with those of urine culture.Measurement data were subject to test of normality.The independent sample t test, Chi-square test or Fisher′s exact probability test were used for comparison between groups. Results:A total of 193 patients were included.The positive detection rate of urine culture was 36.3% (70/193).Among 42 patients who underwent mNGS testing, 37 cases (88.1%) tested positive.The positive detection rate of mNGS was significantly higher than that of urine culture ( χ2=37.357, P<0.001).It took significantly less time to report mNGS results than to report urine culture results ( Z=3.524, P<0.001).In the 42 cases that underwent mNGS testing, 5 cases (11.9%) were negative for urine pathogens by both methods, and 21 cases (50.0%) were positive by mNGS but negative by urine culture.Among the remaining 16 cases (38.1%) positive by both mNGS and urine culture, 14 cases (33.3%) achieved fully matching results, 1 case (2.4%) was fully mismatched, and 1 case (2.4%) was partially matched.Comparison of the positive detection rate and the duration of anti-infective treatment prior to specimen collection between urine culture and mNGS showed that the median durations for urine culture and mNGS positivity were 5 and 20 days, and the difference was statistically significant ( χ2=0.537, P<0.001). Conclusions:mNGS technology has high sensitivity for diagnosing pathogens in pediatric UTI.Compared with urine culture, mNGS provides good consistency and significantly shortens the detection time.The positive detection rate is less affected by antimicrobial treatment.For children with UTI, especially those who have failed empirical anti-infective treatment and whose pathogen cannot be identified by urine culture, mNGS testing is recommended as early as possible.

Objective:To evaluate the efficacy and safety of rituximab (RTX) in children with steroid resistant nephrotic syndrome (SRNS).Methods:The was a retrospective observational study. A retrospective analysis was conducted on the clinical data of 14 children with SRNS who received RTX treatment in the Department of Nephrology, Children's Hospital Affiliated to Capital Institute of Pediatrics from July 2021 to August 2023. The changes in urinary protein content, renal function, serum albumin, immunoglobulin and other indicators before and after RTX medication were compared to evaluate the clinical efficacy and safety of RTX treatment for SRNS.Results:A total of 14 children with SRNS were selected for this study, with a male to female ratio of 6:8. The age of onset of kidney disease was (4.36±3.12) years, and 8 of them underwent kidney biopsy. Among them, 6 cases showed focal segmental glomerulosclerosis in renal pathology, and 2 cases showed minimal change disease. The age of 14 children who first used RTX was (8.45±3.98) years old, with a dose of 375 mg/m 2 and a maximum dose of 500 mg. The number of children who had used 2, 3, 4, and 5 doses of RTX was 6, 6, 1, and 1, respectively. RTX was administered orally with compound sulfamethoxazole to prevent infection. Glucocorticoids and immunosuppressants were discontinued 4.0(2.5, 6.5) months after the first dose of RTX. The median follow-up time was 10.5(6.0, 18.3) months. By the end of the 3-month, 6-month, and follow-up endpoints, the complete remission rates of kidney disease in the children were 100.0%(14/14), 85.7%(12/14), and 64.3%(9/14), respectively. Five children experienced kidney disease recurrence. Compared with before the first dose of RTX treatment, the serum albumin and height significantly increased, while body mass index significantly decreased at the end of follow-up (all P<0.05). There was no statistically significant difference in urinary protein content, renal function, and IgG (all P>0.05). During the RTX treatment, all 14 children did not experience any infusion reaction, and there were no serious infections during follow-up. One case was diagnosed with hypogammaglobulinemia. Conclusions:RTX can improve the remission rate and recurrence rate of SRNS children, reduce the dosage of glucocorticoids and related drug untoward reaction, significantly improve patient height and BMI, with minimal side effects. Especially for SRNS patients who cannot be relieved by the combination of glucocorticoids and immunosuppressants, RTX may be considered.

Objective:To analyze the clinical characteristics of renal abscess in children and provide suggestions for early diagnosis and treatment.Methods:The clinical data including general information, laboratory data, imaging results, treatment and prognosis of 20 pediatric patients with renal abscess admitted to the Department of Nephrology, Capital Center for Children's Health Capital Medical University were analyzed retrospectively.Results:A total of 8 males and 12 females were enrolled. The age of onset was 3.0 (0.8, 9.0) years. All cases had fever. Six cases presented with abdominal pain, 6 cases had poor appetite, 5 cases had vomiting and 5 cases urinary tract irritation symptoms. Laboratory data showed elevated white blood cells 20.4 (17.4,26.3)×10 9/L, C-reactive protein 126 (77, 154)mg/L, erythrocyte sedimentation rate 60 (41,73) mm/1 h in 20 cases and procalcitonin 4.7 (1.2,33.5)μg/L in 10 cases. Totally 18 cases had pyuria. Urine culture was positive in 8 cases. Enterococcus faecium and Pseudomonas aeruginosa was detected in 2 cases. Klebsiella pneumoniae was found in 1 case after performing blood culture. Renal abscess was confirmed in all cases by doing contrast-enhanced CT scan, while only 9 cases with abscesses were identified by using renal ultrasound. There were 14 cases with renal abscess formation confirmed at onset by performing magnetic resonance imaging. Nine cases were accompanied with congenital anomalies of the kidney and urinary tract. All cases received conservative medical treatment. Intravenous broad-spectrum antibiotics were administered for 23 (14, 39) d initially, while the medication in 11 cases were upgraded to meropenem or imipenem. Oral antibiotics were continued for 23 (14, 28) d after discharge in all cases. Within 1 year of follow-up, except for 1 case of recurrence, the others had a favorable prognosis. Conclusions:Renal abscess should be suspected for children presenting with unexplained fever, vomiting, abdominal pain, elevated white blood cell count, C-reactive protein, erythrocyte sedimentation rate and pyuria. Ultrasonography is suitable for screening and follow-up, while CT or magnetic resonance imaging can be used to confirm the diagnosis. Conservative management with broad-spectrum antibiotics is effective and can be considered the first-line therapy for pediatric renal abscess.

Objective:To summarize and analyze the clinical phenotype and genotype characteristics of atypical hemolytic uremic syndrome (aHUS) in Chinese children.Methods:It was a retrospective study. The clinical data and genetic results of 6 children with aHUS admitted to Children's Hospital Affiliated to Capital Institute of Pediatrics from May 2016 to October 2022 were analyzed, and literature on Chinese aHUS children with genetic screening data by searching databases such as Wanfang, CNKI, and PubMed were reviewed and summarized. Through literature search, the children with aHUS were divided into genetic variation group and non-genetic variation group according to the results of genetic testing, and the differences of clinical phenotype, laboratory examination, follow-up and outcomes were compared between the two groups. Logistic regression method was used to analyze the risk difference of disease recurrence, end-stage kidney disease and death between genetic variation group and non-genetic variation group.Results:Among the 6 aHUS children in this center, there were 1 male and 5 females, with onset age of 7 months to 10 years old. Four patients had gene variations, including 1 patient of complement factor H ( CFH) gene variation, 1 patient of C3 gene variation, and 2 patients of CFHR1 combined with CFHR3 gene variation. Six children had gross hematuria, proteinuria, hypertension and decreased complement C3. The mean values of serum creatinine in 4 genetic variation and 2 non-genetic variation children were 153.9 μmol/L and 214.3 μmol/L, respectively; the mean values of estimated glomerular filtration rate were 26.4 ml·min -1·(1.73 m 2) -1 and 28.9 ml·min -1·(1.73 m 2) -1, respectively; the mean values of hemoglobin were 81 g/L and 57 g/L; the mean values of platelet were 46×10 9/L and 71×10 9/L; the mean values of lactic dehydrogenase were 2 408 U/L and 2 106 U/L, respectively; there were 1 and 2 cases of positive CFH antibody, and 1 and 1 case of nervous system complication, respectively. Ninety-seven aHUS children were retrieved including the reported 6 cases in this center, with 60 males and 37 females, and median onset age of 5 years old. The positive detection rate of genetic variation was 58.8% (57/97). The main type of genetic variation was CFHR gene variation (43.9%, 25/57), followed by CFH gene variation (33.3%, 19/57).There was no significant difference in onset age, sex distribution, proportions of gross hematuria, massive proteinuria, hypertension, complement C3 decline, positive CFH antibody and treatment method, platelet, and lactic dehydrogenase between genetic variation group and non-genetic variation group (all P>0.05). Compared with the genetic variation group, non-genetic variation group had higher serum creatinine ( Z=2.311, P=0.021) and lower hemoglobin ( Z=-2.636, P=0.008). The median follow-up time in genetic variation group and non-genetic variation group was 1 year and 2 years, respectively. The proportions of non-remission and recurrence in the genetic variation group were significantly higher than those in non-genetic variation group ( χ2=12.016, P=0.002; χ2=4.689, P=0.030). Logistic regression analysis showed that the recurrence risk of aHUS in children with genetic mutations was higher than that in children with non-genetic mutations ( OR=2.807, 95% CI 1.014-7.772). Conclusions:The main type of aHUS gene variation in Chinese children is CFHR gene variation, and the children with gene variation have poor prognosis and a higher risk of recurrence.

It was a retrospective study. The case data of thirteen patients diagnosed with methylmalonic acidemia (MMA) combined with hemolytic uremic syndrome (HUS) hospitalized at the Children's Hospital Affiliated to Capital Institute of Pediatrics from January 2010 to December 2022 were analyzed, to explore clinical and genetic characteristics of MMA combined with HUS (MMA-HUS). The onset age of MMA was 18 days to 5 years old, with 11 patients of early onset and 2 patients of late onset, 4 patients of simple MMA and 9 patients of combined MMA, and 7 patients of secondary hypertension and 3 patients of secondary pulmonary arterial hypertension. Among 13 patients, 7 patients underwent genetic testing, with 1 patient of MMUT gene mutation and 6 patients of MMACHC gene mutation. The mutation sites were all from their parents and all were known pathogenic variants. Among them, 5 patients had MMACHC gene c.80A>G heterozygous variation, accompanied by cardiovascular involvement. After etiological and symptomatic treatment, 6 patients improved, 7 patients died of multiple organ failure, and all the deaths were early-onset MMA. This study shows that MMA-HUS is more common in early-onset MMA, with a severe condition and a high mortality rate. Its prognosis is related to multiple factors such as genotype, diagnosis and treatment timing. c.80A>G variation of MMACHC gene may be related to HUS and cardiovascular involvement.