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Objective@#To evaluate the clinical and laboratory characteristics, therapeutic drugs, and prognosis of juvenile systemic sclerosis (JSSc) at a single center in Korea. @*Methods@#This study was a retrospective analysis of patients with JSSc aged <16 years at disease onset and who were treated at our hospital between January 1992 and April 2023. All patients met the Pediatric Rheumatology European Society/American College of Rheumatology/European League against Rheumatism provisional classification criteria for JSSc, and those with localized scleroderma (morphea) were excluded. @*Results@#Among the 13 patients, proximal skin sclerosis (100%), Raynaud’s phenomenon (RP) (84.6%), and sclerodactyly (69.2%) were present at the time of diagnosis. The most common symptom before diagnosis was RP, which was present in 10 patients (76.9%), whereas proximal skin sclerosis was observed in only five patients (38.5%). Thirteen patients had positive anti-nuclear antibody (ANA). At the time of diagnosis, five individuals had findings suggestive of interstitial lung disease (ILD) on a pulmonary function test (PFT) or chest computed tomography (CT), two of whom were asymptomatic. During follow-up, three patients developed ILD, one developed renal dysfunction, one developed heart disease, and none died. @*Conclusion@#This study was the first descriptive analysis of clinical features of JSSc in South Korea. Clinical suspicion is essential for diagnosing JSSc in patients with RP, especially if ANA is positive; however, proximal skin sclerosis, which is crucial for diagnosing JSSc, was unrecognized in the early phase of the disease. PFT should be considered even if a patient is asymptomatic or has normal chest CT.
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Stimulator of interferon gene (STING)-associated vasculopathy with onset in infancy (SAVI) is an extremely rare autoinflammatory disease. We present the case of a female Korean patient with early-onset interstitial lung disease who was initially suspected to have systemic lupus erythematosus (SLE) but was ultimately diagnosed with SAVI. The patient exhibited signs of interstitial lung disease and cutaneous manifestations before the age of 1 year and continued to have recurrent fever accompanied by pulmonary infiltrates. Based on positive findings for antibodies associated with SLE, such as antinuclear antibodies and anti-double-stranded DNA, the pulmonary involvement was considered a manifestation of SLE. Another significant symptom was recurrent skin ulceration, which led to partial spontaneous amputation of most of the toes due to inflammation. Given the early onset of interstitial lung disease, severe skin ulcers, and symptoms resembling SLE, autoinflammatory syndrome, especially SAVI was suspected.Following confirmation by genetic testing at age 29 years, the patient was started on tofacitinib, a Janus kinase inhibitor. Despite the prolonged use of multiple immunosuppressive therapies, the patient’s lung condition continued to worsen, ultimately requiring lung transplantation. This observational report highlights the importance of considering SAVI as a potential diagnosis when manifestations of interstitial lung disease are observed during infancy. Early proactive treatment is crucial for lung involvement, as this can have long-term effects on patient’s prognosis.
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Purpose@#This article was to collect data on the safety of coronavirus disease 2019 (COVID-19) vaccines in children with underlying medical conditions. @*Methods@#We constructed a prospective cohort of children and adolescents aged 5 to 19 years who had received at least one dose of COVID-19 vaccine. Patients diagnosed with and treated for chronic kidney disease, autoimmune disease, or other chronic conditions at the Seoul National University Children’s Hospital were recruited from June to December 2022. A mobile survey questionnaire was sent to their guardians. The presence of adverse events on the day (day 0), 3 weeks (day 21), and 6 months (day 180) after the 1st dose of COVID-19 vaccine was recorded by the guardians. @*Results@#A total of 73 children participated. The median age was 14 years, and 64.4% of the patients were male. On the day of immunization, 65.8% of the patients reported at least one adverse event. Pain at the injection site, fatigue, headache, arthralgia, and myalgia were the most common symptoms. The prevalence of adverse events decreased over time (65.8% on day 0, 27.4% between days 0 and 21, and 24.6% between days 21 and 180). Severe acute respiratory syndrome coronavirus 2 infection after the 1st dose occurred in 17 patients (23.3%) and one of the patients (5.88%) was hospitalized due to infection. @*Conclusions@#Adverse events after COVID-19 vaccination were generally mild in children and adolescents with underlying medical conditions. Our findings provide evidence for the safety of COVID-19 vaccination in the vulnerable pediatric population.
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Purpose@#Angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers (ARBs) are frequently employed to counteract the detrimental effects of proteinuria on glomerular diseases. However, the effects of ARBs remain poorly examined in pediatric patients with immunoglobulin A (IgA) nephropathy. Herein, we evaluated the efficacy and safety of losartan, an ARB, in pediatric IgA nephropathy with proteinuria. @*Methods@#This prospective, single-arm, multicenter study included children with IgA nephropathy exhibiting proteinuria. Changes in proteinuria, blood pressure, and kidney function were prospectively evaluated before and 4 and 24 weeks after losartan administration. The primary endpoint was the difference in proteinuria between baseline and 24 weeks. @*Results@#In total, 29 patients were enrolled and received losartan treatment. The full analysis set included 28 patients who received losartan at least once and had pre- and post-urinary protein to creatinine ratio measurements (n=28). The per-protocol analysis group included 22 patients who completed all scheduled visits without any serious violations during the study period. In both groups, the mean log (urine protein to creatinine ratio) value decreased significantly at 6 months. After 24 weeks, the urinary protein to creatinine ratio decreased by more than 50% in approximately 40% of the patients. The glomerular filtration rate was not significantly altered during the observation period. @*Conclusions@#Losartan decreased proteinuria without decreasing kidney function in patients with IgA nephropathy over 24 weeks. Losartan could be safely employed to reduce proteinuria in this patient population. ClinicalTrials.gov trial registration (NCT0223277)
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Pediatric rheumatologic diseases are rare systemic diseases that can involve various organs, including the kidneys. Each rheumatologic disease can exhibit characteristic renal involvement, which requires proper treatment and diagnosis. In this review, we discuss renal involvement in classic rheumatologic diseases, including juvenile idiopathic arthritis, Sjogren's syndrome, systemic sclerosis, and juvenile dermatomyositis. Reviews addressing lupus nephritis and antineutrophil cytoplasmic antibody-associated renal disease are complex and tend to cover a wide array of topics, and thus were excluded from this review.
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Background@#The clinical features of pediatric rhabdomyolysis differ from those of the adults with rhabdomyolysis; however, multicenter studies are lacking. This study aimed to investigate the characteristics of pediatric rhabdomyolysis and reveal the risk factors for acute kidney injury (AKI) in such cases. @*Methods@#This retrospective study analyzed the medical records of children and adolescents diagnosed with rhabdomyolysis at 23 hospitals in South Korea between January 2007 and December 2016. @*Results@#Among 880 patients, those aged 3 to 5 years old composed the largest subgroup (19.4%), and all age subgroups were predominantly male. The incidence of AKI was 11.3%. Neurological disorders (53%) and infection (44%) were the most common underlying disorder and cause of rhabdomyolysis, respectively. The median age at diagnosis in the AKI subgroup was older than that in the non-AKI subgroup (12.2 years vs. 8.0 years). There were no significant differences in body mass index, myalgia, dark-colored urine, or the number of causal factors between the two AKI-status subgroups. The multivariate logistic regression model indicated that the following factors were independently associated with AKI: multiorgan failure, presence of an underlying disorder, strong positive urine occult blood, increased aspartate aminotransferase and uric acid levels, and reduced calcium levels. @*Conclusions@#Our study revealed characteristic clinical and laboratory features of rhabdomyolysis in a Korean pediatric population and highlighted the risk factors for AKI in these cases. Our findings will contribute to a greater understanding of pediatric rhabdomyolysis and may enable early intervention against rhabdomyolysis-induced AKI.
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Purpose@#Congenital pulmonary airway malformation (CPAM) is a rare developmental abnormality of the lungs. We investigated clinical characteristics of CPAM based on patient age at diagnosis. @*Methods@#In this retrospective study, we analyzed the medical records of 51 patients diagnosed with CPAM at Pusan National University Hospital between January 2000 and December 2019. @*Results@#We investigated 39 children and 12 adults. The mean age at the diagnosis of the patients was 15.9± 14.3 years. The mean ages of children and adults at the time of diagnosis of CPAM were 6.8± 5.8 years and 31.2± 10.2 years, respectively. Among the 51 patients investigated, 20 (39%) were asymptomatic and 31 (61%) showed clinical symptoms, such as dry cough, recurrent respiratory infections, and dyspnea at the time of diagnosis. Notably, clinical symptoms at diagnosis were observed in 28 children (72%) and in only 3 adults (25%) (P= 0.006), and children were more symptomatic than adults. Children with large cysts tended to be more symptomatic than those with small cysts (P< 0.001). Combined anomalies were detected in 12 patients (23%). Patients with cystic lesions in the right lower lobe of the lung showed a higher prevalence of combined anomalies (P= 0.015). Surgical resection was performed in 40 patients (78%), and all patients showed good prognosis. @*Conclusion@#This study revealed that the presence of clinical symptoms of CPAM differed between children and adults, depending on the age at diagnosis and that patients with cysts in the right lower lobe of the lungs tended to show a higher prevalence of combined anomalies.
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Background@#Chronic kidney disease (CKD) has a negative impact on growth and development in children and is a risk factor for neurocognitive impairment; however, there is limited research on the cognitive function of children and adolescents with CKD. This study therefore aimed to investigate the mean intelligence and risk factors for low intelligence in children and adolescents with CKD. @*Methods@#Eighty-one patients with CKD under 18 years old were included in the KoreaN cohort study for Outcomes in patients With Pediatric Chronic Kidney Disease (KNOW-Ped CKD). Participants completed either the Wechsler Intelligence Scale for Children (6–16 years), or Wechsler Adult Intelligence Scale (> 16 years). @*Results@#The mean full-scale intelligence quotient (IQ) was 91 ± 19; 24.7% of participants scored a full-scale IQ below 80. Participants with a short stature (height Z scores < −1.88), failure to thrive (weight Z scores < −1.65), more severe CKD stage (≥ IIIb), longer duration of CKD (≥ 5 years), and those who were Medicare or Medicaid beneficiaries, had significantly lower mean full-scale IQs. @*Conclusion@#On linear regression analysis, the association between the full-scale IQ, and longer duration of CKD and growth failure, remained significant after controlling for demographic and clinical variables. It is therefore necessary to investigate cognitive impairment in pediatric patients with CKD who exhibit growth failure or for a longer postmorbid period. It is believed that early interventions, such as kidney transplantation, will have a positive effect on IQ in children with CKD, as the disease negatively affects IQ due to poor glomerular filtration rate over time.
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Background@#Chronic kidney disease (CKD) has a negative impact on growth and development in children and is a risk factor for neurocognitive impairment; however, there is limited research on the cognitive function of children and adolescents with CKD. This study therefore aimed to investigate the mean intelligence and risk factors for low intelligence in children and adolescents with CKD. @*Methods@#Eighty-one patients with CKD under 18 years old were included in the KoreaN cohort study for Outcomes in patients With Pediatric Chronic Kidney Disease (KNOW-Ped CKD). Participants completed either the Wechsler Intelligence Scale for Children (6–16 years), or Wechsler Adult Intelligence Scale (> 16 years). @*Results@#The mean full-scale intelligence quotient (IQ) was 91 ± 19; 24.7% of participants scored a full-scale IQ below 80. Participants with a short stature (height Z scores < −1.88), failure to thrive (weight Z scores < −1.65), more severe CKD stage (≥ IIIb), longer duration of CKD (≥ 5 years), and those who were Medicare or Medicaid beneficiaries, had significantly lower mean full-scale IQs. @*Conclusion@#On linear regression analysis, the association between the full-scale IQ, and longer duration of CKD and growth failure, remained significant after controlling for demographic and clinical variables. It is therefore necessary to investigate cognitive impairment in pediatric patients with CKD who exhibit growth failure or for a longer postmorbid period. It is believed that early interventions, such as kidney transplantation, will have a positive effect on IQ in children with CKD, as the disease negatively affects IQ due to poor glomerular filtration rate over time.
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Haploinsufficiency of A20 (HA20) is a newly described autoinflammatory disease caused by loss-of-function mutations in the TNFAIP3 gene. Clinical phenotypes are heterogenous and resemble Behçet's disease, juvenile idiopathic arthritis, inflammatory bowel disease, or periodic fever syndrome, with symptoms developing at an early age. Here, we report the first case of infantile familial HA20 in Korea, which mimics neonatal lupus erythematosus (NLE). A 2-month-old infant exhibited symptoms including recurrent fever, erythematous rashes, and oral ulcers, with elevated liver enzymes, and tested positive for several autoantibodies, similar to systemic lupus erythematosus (SLE); therefore, she was suspected to have NLE. However, six months after birth, symptoms and autoantibodies persisted. Then, we considered the possibility of other diseases that could cause early onset rashes and abnormal autoantibodies, including autoinflammatory syndrome, monogenic SLE, or complement deficiency, all of which are rare. The detailed family history revealed that her father had recurrent symptoms, including oral and genital ulcers, knee arthralgia, abdominal pain, and diarrhea. These Behcet-like symptoms last for many years since he was a teenager, and he takes medications irregularly only when those are severe, but doesn't want the full-scale treatment. Whole-exome sequencing was conducted to identify a possible genetic disorder, which manifested as pathogenic variant nonsense mutation in the TNFAIP3 gene, leading to HA20. In conclusion, HA20 should be considered in the differential diagnosis of an infant with an early-onset dominantly inherited inflammatory disease that presents with recurrent oral and genital ulcerations and fluctuating autoantibodies. Additionally, it also should be considered in an infant with suspected NLE, whose symptoms and abnormal autoantibodies persist.
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Purpose@#To investigate the effect of lifestyle changes on patterns of carbon monoxide (CO) exposure and the association between neurologic symptoms and outcomes in Korean children with CO intoxication. @*Methods@#We reviewed the medical records of patients (< 18 years) with CO intoxication who visited the emergency department of Pusan National University Hospital between February 2012 and January 2020. We collected clinical findings, including age and sex, transfer from other hospitals, source, time and duration of exposure, manifestations with neurologic symptoms (syncope, seizure, and altered mental status), intensive care unit hospitalization, hospital length of stay, implementation of hyperbaric oxygen therapy, and findings of neuroimaging. These variables were compared between children with and without neurologic symptoms. In addition, levels of carboxyhemoglobin and lactate were compared between patients with and without specific manifestations. @*Results@#The enrolled 47 patients’ median age was 10 years (interquartile range, 4.5-14.0). The most common source of exposure was fire (46.8%), followed by camping (23.4%). The most common times of exposure were night (44.7%) and winter (44.7%). The patients with neurologic symptoms (14 [29.8%]) showed longer duration of exposure and hospital length of stay (P < 0.001 and P = 0.007, respectively). Of the 14 patients, 2 were hospitalized to the intensive care unit without an in-hospital mortality. A significant association was found between dyspnea and lactate level (P = 0.049), also between syncope or presyncope and carboxy hemoglobin level (P = 0.017). @*Conclusion@#CO intoxication in Korean children is most often caused by fire and camping, and at night and in winter. There is a correlation between neurologic symptoms and duration of exposure to CO.
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BACKGROUND AND OBJECTIVES@#Hypertension is becoming one of the most common health conditions in children and adolescents due to increasing childhood obesity. We aimed to provide the auscultatory blood pressure (BP) normative reference values for Korean non-overweight children and adolescents.@*METHODS@#BP measurements in children and adolescents aged 10 to 18 years were performed in the Korean National Health and Nutrition Examination Survey (KNHANES) from 1998 to 2016. BP was measured using a mercury sphygmomanometer. Sex-, age- and height-specific systolic BP (SBP) and diastolic BP (DBP) percentiles were calculated in the non-overweight children (n=10,442). We used the General Additive Model for Location Scale and Shape method to calculate BP percentiles.@*RESULTS@#The 50th, 90th, 95th, and 99th percentiles of SBP and DBP tables and graphs of non-overweight children and adolescents aged 10 to 18 years were presented by age and height percentiles. We found that the SBP and DBP at the 95th percentile were well correlated with height. The BP tables presented by height contained BP values from 124 cm to 190 cm for boys and from 120 cm to 178 cm for girls. Boys had higher SBP and DBP.@*CONCLUSIONS@#We provided the sex-, age- and height-specific auscultatory BP values using the KNHANES big data. These may be useful in diagnosis and treatment of hypertension in Korean children and adolescents.
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Succinyl-CoA:3-ketoacid CoA transferase (SCOT) deficiency is a rare inborn error of ketone body utilization, characterized by episodic or permanent ketosis. SCOT deficiency is caused by mutations in the OXCT1 gene, which is mapped to 5p13 and consists of 17 exons. A 12-month-old girl presented with severe ketoacidosis and was treated with continuous renal replacement therapy. She had two previously unrecognized mild-form episodes of ketoacidosis followed by febrile illness. While high levels of ketone bodies were found in her blood and urine, other laboratory investigations, including serum glucose, were unremarkable. We identified novel compound heterozygous mutations in OXCT1:c.1118T>G (p.Ile373Ser) and a large deletion ranging from exon 8 to 16 through targeted exome sequencing and microarray analysis. This is the first Korean case of SCOT deficiency caused by novel mutations in OXCT1, resulting in life-threatening ketoacidosis. In patients with unexplained episodic ketosis, or high anion gap metabolic acidosis in infancy, an inherited disorder in ketone body metabolism should be suspected.
Subject(s)
Female , Humans , Infant , Acid-Base Equilibrium , Acidosis , Blood Glucose , Exome , Exons , Ketone Bodies , Ketosis , Metabolism , Microarray Analysis , Renal Replacement Therapy , TransferasesABSTRACT
BACKGROUND: Primary hyperoxaluria (PH), a rare inborn error of glyoxylate meta bolism causing overproduction of oxalate, is classified into three genetic subgroups: type 1–3 (PH1–PH3) caused by AGXT, GRHPR , and HOGA1 gene mutations, respectively. We performed a retrospective case series study of Korean pediatric patients with PH.METHODS: In total, 11 unrelated pediatric patients were recruited and their phenotypes and genotypes were analyzed by a retrospective review of their medical records.RESULTS: Mutational analyses revealed biallelic AGXT mutations (PH1) in nine patients and a single heterozygous GRHPR and HOGA1 mutation in one patient each. The c.33dupC was the most common AGXT mutation with an allelic frequency of 44%. The median age of onset was 3 months (range, 2 months-3 years), and eight patients with PH1 presented with end stage renal disease (ESRD). Patients with two truncating mutations showed an earlier age of onset and more frequent retinal involvement than patients with one truncating mutation. Among eight PH1 patients presenting with ESRD, five patients were treated with intensive dialysis followed by liver transplantation (n=5) with/without subsequent kidney transplantation (n=3).CONCLUSION: Most patients presented with severe infantile forms of PH. Patients with two truncating mutations displayed more severe phenotypes than those of patients with one truncating mutation. Sequential liver and kidney transplantation was adopted for PH1 patients presenting with ESRD. A larger nation-wide multicenter study is needed to confirm the genotype-phenotype correlations and outcomes of organ transplantation.
Subject(s)
Humans , Age of Onset , Dialysis , Genetic Association Studies , Genotype , Hydrogen-Ion Concentration , Hyperoxaluria, Primary , Kidney Failure, Chronic , Kidney Transplantation , Liver , Liver Transplantation , Medical Records , Organ Transplantation , Phenotype , Retinaldehyde , Retrospective Studies , TransplantsABSTRACT
The authors regret that there was an important error in the results in Table 1; the ATP7A mutations detected in Patients 2 and 14 were incorrectly noted.
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BACKGROUND: Menkes disease (MD) is a rare X-linked hereditary multisystemic disorder that is caused by dysfunction of copper metabolism. Patients with MD typically present with progressive neurodegeneration, some connective tissue abnormalities, and characteristic “kinky” hair. In addition, various types of urological complications are frequent in MD because of underlying connective tissue abnormalities. In this study, we studied the clinical features and outcomes of MD, focusing on urological complications. METHODS: A total of 14 unrelated Korean pediatric patients (13 boys and 1 girl) with MD were recruited, and their phenotypes and genotypes were analyzed by retrospective review of their medical records. RESULTS: All the patients had early-onset neurological deficit, including developmental delay, seizures, and hypotonia. The girl patient showed normal serum copper and ceruloplasmin levels as well as milder symptoms. Mutational analysis of the ATP7A gene revealed 11 different mutations in 12 patients. Bladder diverticula was the most frequent urological complication: 8 (57.1%) in the 14 patients or 8 (72.7%) in the 11 patients who underwent urological evaluation. Urological imaging studies were performed essentially for the evaluation of accompanying urinary tract infections. Four patients had stage II chronic kidney disease at the last follow-up. CONCLUSION: Urologic problems occurred frequently in MD, with bladder diverticula being the most common. Therefore, urological imaging studies and appropriate management of urological complications, which may prevent or reduce the development of urinary tract infections and renal parenchymal damage, are required in all patients with MD.
Subject(s)
Female , Humans , Ceruloplasmin , Connective Tissue , Copper , Diverticulum , Follow-Up Studies , Genotype , Hair , Medical Records , Menkes Kinky Hair Syndrome , Metabolism , Muscle Hypotonia , Phenotype , Renal Insufficiency, Chronic , Retrospective Studies , Seizures , Urinary Bladder , Urinary Tract InfectionsABSTRACT
BACKGROUND AND OBJECTIVES: Hypertension is becoming one of the most common health conditions in children and adolescents due to increasing childhood obesity. We aimed to provide the auscultatory blood pressure (BP) normative reference values for Korean non-overweight children and adolescents. METHODS: BP measurements in children and adolescents aged 10 to 18 years were performed in the Korean National Health and Nutrition Examination Survey (KNHANES) from 1998 to 2016. BP was measured using a mercury sphygmomanometer. Sex-, age- and height-specific systolic BP (SBP) and diastolic BP (DBP) percentiles were calculated in the non-overweight children (n=10,442). We used the General Additive Model for Location Scale and Shape method to calculate BP percentiles. RESULTS: The 50th, 90th, 95th, and 99th percentiles of SBP and DBP tables and graphs of non-overweight children and adolescents aged 10 to 18 years were presented by age and height percentiles. We found that the SBP and DBP at the 95th percentile were well correlated with height. The BP tables presented by height contained BP values from 124 cm to 190 cm for boys and from 120 cm to 178 cm for girls. Boys had higher SBP and DBP. CONCLUSIONS: We provided the sex-, age- and height-specific auscultatory BP values using the KNHANES big data. These may be useful in diagnosis and treatment of hypertension in Korean children and adolescents.
Subject(s)
Adolescent , Child , Female , Humans , Auscultation , Blood Pressure , Diagnosis , Hypertension , Korea , Methods , Nutrition Surveys , Pediatric Obesity , Reference Values , SphygmomanometersABSTRACT
Hemolytic uremic syndrome (HUS) is often encountered in children with acute kidney injury. Besides the well-known shiga toxin-producing Escherichia coli-associated HUS, atypical HUS (aHUS) caused by genetic complement dysregulation has been studied recently. aHUS is a rare, chronic, and devastating disorder that progressively damages systemic organs, resulting in stroke, end-stage renal disease, and death. The traditional treatment for aHUS is mainly plasmapheresis or plasma infusion; however, many children with aHUS will progress to chronic kidney disease despite plasma therapy. Eculizumab is a newly developed biologic that blocks the terminal complement pathway and has been successfully used in the treatment of aHUS. Currently, several guidelines for aHUS, including the Korean guideline, recommend eculizumab as the first-line therapy in children with aHUS. Moreover, life-long eculizumab therapy is generally recommended. Further studies on discontinuation of eculizumab are needed.
Subject(s)
Child , Humans , Acute Kidney Injury , Atypical Hemolytic Uremic Syndrome , Complement System Proteins , Escherichia , Hemolytic-Uremic Syndrome , Kidney Failure, Chronic , Plasma , Plasmapheresis , Renal Insufficiency, Chronic , StrokeABSTRACT
Rituximab (RTX) is a chimeric monoclonal antibody that inhibits CD20-mediated B-cell proliferation and differentiation. Several studies have examined its use in intractable nephrotic syndrome (NS) with some positive results. However, those studies examined such effects for a short-term period of 1 year, and some patients continued to relapse after a lapse in RTX treatment. Our use of RTX as a maintenance therapy (RTX injection when the CD19 cell count exceeded 100–200/µL before relapse) showed some noticeable efficacy. We used RTX in 19 patients with steroid-dependent NS (SDNS). In 12 patients treated with RTX maintenance therapy, only one relapse occurred. The mean treatment period was 23.4±12.7 months, and the mean number of RTX administrations was 3.9±1.6. The relapse rates were decreased (from 2.68/year to 0.04/year), and the drug-free period also increased (from 22.5 days/year to 357.1 days/year) during maintenance therapy. The other seven patients were treated with one cycle of RTX or additional cycles in case of relapse (non-maintenance therapy). Relapse rates were significantly decreased after RTX treatment (from 1.76/year to 0.96/year, P=0.017). The relapse-free period was 15.55±7.38 (range, 5.3–30.7) months. No severe side effects of RTX were found except for a hypersensitivity reaction such as fever and chills during its infusion. In conclusion, RTX is considered an effective and safe option to reduce the relapse rate by a single- or maintenance-interval therapy in SDNS.