Low protein Z levels in children with nephrotic syndrome

Acquired deficiency of anticoagulant proteins, due to loss in the urine, has been proposed as one of the major thrombogenic alterations in nephrotic syndrome (NS). Protein Z (PZ) is a single-chain vitamin K-dependent glycoprotein. Low PZ levels are reported to be a risk factor for thrombosis. The aim of this study was to investigate protein Z and other natural anticoagulant levels in children with NS. Thirty children aged between 1.5 and 12 years with NS (Groups I and II) and 19 age-and-sex-matched healthy controls (Group III) were enrolled into the study. Patients were divided into two groups: Group I (proteinuria >40 mg/m²/hr) and Group II (patients in remission). Plasma PZ levels in Group I were significantly lower than Group II (p=0.009) and group III (p=0.018). Plasma levels of AT III for Group I were significantly lower than for Groups II and III (p=0.009, p=0.005, respectively). Protein C levels in Group I were higher than in Group II and Group III (p=0.002, p=0.000, respectively). Protein Z levels positively correlated with serum total protein and albumin levels (p=0.003, p=0.003, respectively) and negatively with the degree of proteinuria (p=0.000). Protein Z levels were positively correlated with AT III (r=0.037, p=0.04). Along with the other coagulation abnormalities, decreased protein Z may contribute to increased risk of thromboembolic complications in children with NS. The negative correlation between proteinuria and PZ level suggests the possibility of renal PZ loss. Further studies are needed to investigate the mechanism and role of decreased PZ in NS.     

Increased cystatin C concentration in urine of nephrotic children

The aim of this study was to evaluate changes in urine and plasma concentrations of cystatin C in children with a relapse of the idiopathic nephrotic syndrome (INS). The study group comprised 12 children with INS with proteinuria and 12 children in an 8-week remission, both treated with steroids. Twelve healthy children served as controls. Cystatin C was detectable in the urine of children with proteinuria. The study suggests that massive proteinuria may influence renal cystatin C handling.     

High-sensitivity C-reactive protein (hs-CRP) level in children with nephrotic syndrome

The aim of this study was to assess the serum concentration of high-sensitivity C-reactive protein (hs-CRP) in children with nephrotic syndrome (NS) treated with prednisone and cyclosporine A (CyA). Patients were divided into three groups: (I) 20 NS children (aged 4–14 years) in relapse and examined twice, (A) before treatment and (B) after proteinuria regression (a 3–4 week course of prednisone therapy); (II) 20 children with steroid-dependent or steroid-resistant NS, treated with CyA, also examined twice, (D) before treatment with CyA, (E) 6 months after therapy. A control group (C) consisted of 20 healthy children. Serum hs-CRP level was determined by a nephelometric method with a Behring Nephelometer 100 Analyzer, Dade Behring. The results showed that median hs-CRP concentration was the highest in children with relapsing steroid-sensitive NS before treatment (IA). After proteinuria regression (IB), the hs-CRP level had decreased and did not differ from that of healthy controls (C) (P > 0.05). In group II, before CyA administration (IID), the level of hs-CRP was normal, but it had increased after 6 months of treatment (IIE) up to a level six-times higher than that of the control group (P < 0.01). We concluded that, in children with steroid-sensitive nephrotic syndrome in relapse, the serum hs-CRP level is increased but returns to normal after 3–4 weeks of glucocorticoid treatment. In children chronically treated with CyA due to NS, serum hs-CRP level increases significantly during the therapy.     

他克莫司在儿童原发性肾病综合征中的应用

目的 研究他克莫司（TAC,FK506）在儿童原发性肾病综合征中的临床应用。 方法 65例患儿入院后根据不同的临床类型联合激素或逐渐减用激素,同时给予口服他克莫司,剂量0.1～0.15 mg/kg,每12小时１次,疗程6～24个月,并监测血药浓度。 结果 65例患儿经他克莫司治疗1～2个月后,尿蛋白逐渐减少;血清白蛋白迅速增加并恢复正常;胆固醇、三酰甘油均有不同程度的改善;总缓解率83.1％;显效时间为7～54 d。随访中12例出现复发。细胞亚群CD4增高时缓解率高。他克莫司药物代谢基因型为3/3型或3/1型缓解率高。微小病变型肾病（MCN）缓解率为96.4％;系膜增生性肾炎（MsPGN）为90.0％;膜性肾病（MN）为2/3;膜增生性肾炎（MPGN）为3/5;局灶节段性肾小球硬化症（FSGS）为4/9。他克莫司起始剂量为0.1～0.15 mg/kg,每12小时１次,治疗浓度控制在5～10 g/L时,本组患儿可获得缓解。12例出现厌食、恶心、呕吐;1例腹痛;2例头痛;1例震颤;3例失眠;4例出现一过性Scr上升;8例N-乙酰氨基葡萄糖苷酶（NAG）轻微增加;6例C3与α-2巨球蛋白增加。部分患儿在1周内恢复正常,其他患儿在他克莫司减药后症状消失。 结论 他克莫司对原发性肾病综合征患儿有良好的疗效,即使患儿肝功能异常、并发结核感染或有严重激素不良反应。他克莫司可替代环孢素A作为新的治疗用药。     

Cyclosporin A absorption profiles in children with nephrotic syndrome

A single blood concentration measurement of Neoral 2 h after administration (C2) is a new concept in therapeutic drug monitoring (TDM). In most adult patients, the concentration of cyclosporin A (CyA) peaks within 2 h after Neoral administration. Therefore, monitoring the area under the concentration-time curve over the first 4 h post-dose (AUC0–4) is considered to be the most reliable strategy for Neoral TDM. In addition, C2 is considered to be the most accurate predictor of AUC0–4, with which C2 correlates best. Thus, in adult patients, C2 monitoring is recommended as the best single-point TDM method for Neoral. However, in paediatric patients, the effectiveness of C2 monitoring is still unclear. We examined the trough concentration (C0), C1, C2, C3, and C4 of CyA in 60 patients (1 to 20 years old, mean age 7.42±0.67 years) who had nephrotic syndrome treated with Neoral. The peak concentration of C0-C4 was C1 or C2 in 38 patients (early peak group) and C3 or C4 in 22 patients (late peak group). C2 in the late peak group was significantly lower than that in the early peak group (422±50.1 vs. 665 ±53.8 ng/ml, P =0.0008), although the administered doses of Neoral and C0 were similar between these groups. Therefore, TDM by C2 using the same standard as in the early peak group might result in an overdose of CyA in the late peak group. As the concentration peaked at 3 h or more after Neoral administration in the late peak group, AUC0–4 does not necessarily reflect the Neoral absorption profile. As more than 33% of the paediatric patients were in the late peak group, TDM by AUC0–4 or C2 should be used carefully in paediatric patients treated with Neoral.     

儿童激素敏感性肾病综合征复发的原因和相关因素分析

目的分析儿童激素敏感性肾病综合征复发的原因,为合理治疗肾病综合征复发提供依据。方法对激素敏感性肾病综合征患儿进行定期随访检查,复发时进行详细病史询问、体检和血尿常规、血生化、血皮质醇测定,分析肾病复发的原因。结果纳入儿童激素敏感性肾病综合征93例,未复发28例（未复发组）;复发65例,共计116例次复发,其中频复发31例（频复发组）,非频复发34例（非频复发组）。复发原因最多为激素依赖和（或）免疫抑制剂依赖（占49．1％）,之后依次为感染（占36．2％）,激素停用（占1．7％）,过敏和接种（占1．7％）,外伤（占1．7％）,10．3％原因不明。血清皮质醇水平减低在频复发组中的比例显著高于非频复发组和未复发组（P〈0．05和P〈0．01）,而严重低血清白蛋白血症和低IgG血症在各组中无显著差别。结论糖皮质激素依赖和感染是儿童激素敏感性肾病综合征复发的主要原因,而血皮质醇水平低下可能是儿童激素敏感性肾病综合征出现频繁复发和激素依赖的重要机制。     

Spectrum of infections in Indian children with nephrotic syndrome

We conducted a retrospective analysis of infections in 154 children (114 boys, 40 girls) with nephrotic syndrome who satisfied the International Study of Kidney Disease in Children criteria. Their mean age at onset of symptoms was 6.2 years (range 6 months to 16 years) and the mean duration of follow-up was 32 months (range 6–55 months). One or more infectious complications were observed in 59 of the 154 children (38%), with urinary tract infection being the commonest (13.7%), followed by pulmonary tuberculosis (10.4%), peritonitis (9.1%), skin infections (5.2%), upper respiratory infections (5.2%), lower respiratory tract infections (3.9%) and pyomeningitis (0.6%). There were 3 deaths, the mortality in 2 patients being attributable to infections. There was no significant difference between children who developed infection and those who didn't in terms of age of onset, sex, duration of disease, serum creatinine, blood urea nitrogen and 24-h proteinuria. However, the children who developed infectious complications had significantly higher serum cholesterol levels (P<0.01) and lower serum albumin levels (P<0.02). The frequency of infections was higher inchildren who were frequent relapsers, steroid dependent and subsequent non-responders (28/60) compared with infrequent relapsers and initial non-responders (29/94).     

Expression of P-glycoprotein in lymphocytes from children with nephrotic syndrome,depending on their steroid response

The aim of this study was to examine the expression of P-glycoprotein (P-gp) in CD3 lymphocytes of children with nephrotic syndrome (NS) in relation to their clinical response to glucocorticoid (GC) treatment. The examinations were performed on two groups. The study group (I) consisted of 88 children aged 2.0–20.0 years with NS, divided according to their clinical response to GC: NFR—non-frequent relapse NS; FR—frequent relapse NS; SD—steroid-dependent NS. The control group (II) consisted of 18 healthy children never treated with GC. We measured P-gp expression on CD3 lymphocytes of patients with NS using a flow cytometry assay. The CD3/P-gp was significantly higher than in controls. The difference was higher in SD (P=0.0001) and FR - (P=0.0002) group. The difference in NFR was smaller. Mean CD3/P-gp (in percent) was twice as high in SD children than in NFR, and the difference, as between FR and NFR, was statistically significant (P<0.01). Worse response to GC or dependency may be due to overexpression of P-gp. Further examinations are necessary to establish whether increased P-gp activity is a result of MDR-1 polymorphism and to determine GC response, or to ascertain if such activity is only a result of GC therapy.     

泼尼松治疗对肾病综合征患儿血清骨钙蛋白和碱性磷酸酶的影响

目的 通过测定。肾病综合征患儿激素不同治疗阶段的血清骨钙蛋白及血清碱性磷酸酶,探讨二者在泼尼松治疗时的内在关系及变化规律。方法 实验分3组:激素治疗前组,激素治疗和对照组。结果 肾病综合征患儿在激素治疗前血清骨钙蛋白水平明显低于对照组(P<0.05),而碱性磷酸酶与对照组相比差异无显著性(P>0.05);应用激素治疗后二者均明显低于激素治疗前组(P<0.05),血清骨钙蛋白水平和血清碱性磷酸酶水平呈正相关(P<0.05)。结论 血清骨钙蛋白和血清碱性磷酸酶都是反映成骨细胞功能活性的指标,激素治疗后患儿的成骨细胞功能受到显著抑制,导致血清骨钙蛋白和碱性磷酸酶水平降低。     

Management of steroid-sensitive nephrotic syndrome in children with type 1 diabetes

Four children with steroid-sensitive nephrotic syndrome (SSNS) coexisting with type 1 diabetes are presented. This number is higher than expected according to the estimated prevalence rates for each disease separately. In three, diabetes preceded nephrotic syndrome (NS), and in one it developed almost simultaneously. None of the patients had hypertension or retinopathy. Two had a renal biopsy: in one it was compatible with minimal change histology (MCH), and the other had MCH and early diabetic nephropathy changes. In addition to the two presented here, in 11 of 12 previously reported cases with biopsy proven SSNS coexisting with type 1 diabetes, the biopsy showed MCH. In none was treatment influenced by biopsy results. However, our experience suggests that daily steroid taper allows easier glycaemic control than alternate day steroids. We conclude that the indications for a renal biopsy in nephrotic children with and without insulin-dependent diabetes mellitus (IDDM) should be similar. Received: 27 July 2001 / Revised: 15 January 2002 / Accepted: 15 January 2002     

环孢素A治疗儿童难治性肾病综合征26例疗效分析

目的探讨环孢素A治疗儿童难治性肾病综合征的临床疗效。方法 26例难治性肾病综合征患儿入院后口服环孢素A,剂量为2～4mg（/kg·d）,同时联合激素治疗,疗程3个月。治疗前及治疗后检测24h尿蛋白定量、血浆白蛋白、血浆胆固醇、尿素氮、血肌酐等指标。结果 26例患儿经治疗后,完全缓解14例,占53.85%;部分缓解10例,占38.46%;未缓解2例,占7.69%。结论环孢素A联合激素能有效治疗难治性肾病综合征。     

Paraoxonase, total antioxidant response, and peroxide levels in children with steroid-sensitive nephrotic syndrome

Reactive oxygen species (ROS) are reported to play a role in inducing the proteinuria of nephrotic syndrome (NS). This study investigated paraoxonase (PON), total antioxidant response (TAR), and oxidant total peroxide together with serum proteins and lipoproteins in children with steroid-sensitive NS. The study included 40 children with steroid-sensitive NS (21 with acute-period NS in group I, 19 nonproteinuric while receiving steroids in group II) and 22 sex- and age-matched formerly nephrotic children in remission weaned from steroids (group III). The following parameters were determined: total peroxide, oxidative stress index (OSI), PON and TAR. Serum proteins and lipoproteins were also determined. Patients in the active phase of NS had significantly lower PON and TAR levels and higher OSI and total peroxide values than those in full remission; no differences were found in PON, TAR, or OSI values of groups I and II. Significant correlations were found between PON, TAR, and total peroxide. Serum total protein had a significantly positive correlation with PON and negative correlation with total peroxide in acute-period NS patients. Our results demonstrate greater oxidative stress and decreased antioxidants in the active phase of steroid-sensitive NS and while patients receive steroids than during full remission. Low-dose alternate-day steroids do not seem to decrease oxidative stress even while proteinuria ceases. Despite some conflicting data increased oxidation and/or decreased antioxidant response may be related to the pathogenesis of steroid-sensitive NS.     

Beneficial effect of second courses of cytotoxic therapy in children with minimal change nephrotic syndrome

Therapeutic guidelines are not available for children with minimal change nephrotic syndrome (MCNS) who experience frequent relapses or develop steroid resistance after a course of cytotoxic therapy. The records of nine children with biopsy-proven MCNS who received two courses of cytotoxic therapy with either chlorambucil or cyclophosphamide were reviewed to evaluate the length of remission, associated side-effects and long-term outcome. Initial cytotoxic therapy was given to five frequent-relapsing patients and four steroid-resistant patients 2–48 months (mean 16 months) following diagnosis of nephrotic syndrome. The second drug was given 4–85 months (mean 27 months) after the first. Steroid-resistant patients attained remissions of 0–81 months (mean 23 months) following the first agent and 13–67 months (mean 32 months) following the second. Frequent-relapsing patients experienced remissions of 0.5–24 months (mean 7.4 months) following the first cytotoxic drug and 3–72 months (mean 22 months) after the second. Remissions following the second agent were equal to or longer than those following the first in the seven patients who received both chlorambucil and cyclophosphamide. In the 19- to 128-month follow-up (mean 66 months), all four steroid-resistant patients experienced infrequent relapses which responded to prednisone. One frequent-relapsing patient remains in remission, three have chronic proteinuria and one still has a frequent-relapsing course. For the select group of patients who become frequent relapsing or steroid resistant after one course of cytotoxic therapy, a second course of cytotoxic therapy may allow time for catch-up growth, as well as improve steroid responsiveness once relapses occur.     

HLA antigens in Arab children with steroid-responsive nephrotic syndrome

Forty-eight Arab patients with steroid-responsive childhood nephrotic syndrome were studied for the frequency of HLA-A,-B,-C and-DR antigens. HLA-DR7 was significantly increased in the patient group (63% vs. 28%,P=0.0002) confirming reports of a DR7 association in other ethnic groups and indicating a universal association with this antigen. HLA-CW6 was also significantly increased (44% vs. 21%,P corr.=0.042). HLA-DQW1 was significantly reduced in the patients (29% vs. 57%,P corr.=0.012) as was HLA-CW4 (6% vs. 24%,P corr.=0.042).     

Clinical analysis of children having primary nephrotic syndrome complicated with posterior reversible encephalopathy syndrome on treatment of immunosuppressants

Objective To explore the relationship between posterior reversible encephalopathy syndrome (PRES) and the treatment of immunosuppressants such as cyclosporine A (CsA) and tacrolimus (FK506) in children with nephrotic syndrome. Methods The clinical data of nephrotic syndrome children with PRES caused by immunosuppressants who were hospitalized in Guangzhou First People's Hospital from June 2014 to May 2017 were collected. Their clinical characteristics, imaging features, treatments and prognosis were analyzed. Results A total of 23 children were enrolled, including 13 children with CsA and 10 children with FK506. In the concurrent of PRES 20 cases were in the activity stage of nephrotic syndrome, with large amounts of urinary protein, obvious edema, hypoalbuminemia and hyperlipidemia; while 3 cases were in the remission of nephrotic syndrome. The main clinical symptoms of PRES were hypertension, headache, epileptic attack, consciousness disorder, visual disorder and so on. Sixty-nine point six percent of children were using high dose immunosuppressive agents, and 78.3% had high drug concentration. The cranial magnetic resonance imaging (MRI) results of 17 patients showed that they had T1 weighted (T1WI) hypointense, T2 weighted (T2WI) and fluid-attenuated inversion recovery (FLAIR) images hyperintense, as well as iso-and slight hypointense of diffusion-weighted image (DWI) in parietal-occipital regions or complicated with frontal lobes or basal nuclei region. Computer tomography (CT) examinations of 6 cases showed low-density focus of the occipital lobes. Children were relieved muscular spasm, debased intracranial hypertension, improved circulation, discontinued or reduced immunosuppressants at the onset of PRES. After these treatments, 21 patients' symptoms and signs disappeared within one week; two patients suffered convulsions 2 times in one week, but recovered after one month. After three months 5 children had MRI and CT re-examination and it showed that their brain lesions disappeared. Conclusions PRES may be related to the dose and blood concentration of immunosuppressive agents. The immunosuppressants for nephrotic syndrome children should be increased gradually with low initiating doses. Physicians need to be precautious to prevent the occurrence of PRES once neurological symptoms occur.     

Clinical significance of sPD-1 and sPD-L1 in serum and urine of children with primary nephrotic syndrome

Objectives To detect the level of soluble programmed death 1 (sPD-1) and soluble programmed death ligand 1 (sPD-L1) in serum and urine of children with primary nephrotic syndrome (PNS), and explore its clinical significance. Methods From July 2017 to November 2017, children with PNS admitted to the Children's Hospital Affiliated to Soochow University were divided into onset group (36 cases) and remission group (33 cases). Thirty healthy children who underwent medical examination for enrollment, undersize or overweight in the outpatient department of pediatric health care and inpatient department of Endocrinology were selected as healthy control group. Serum and urine samples were collected, in which the levels of sPD-1 and sPD-L1 were detected by enzyme-linked immunosorbent assay (ELISA). The correlation between serum and urine sPD-1, sPD-L1 levels and lymphocyte subsets, urinary protein were analyzed by Pearson and Spearman correlation analysis. Results The level of sPD-1 in serum was lower in remission group than those in healthy control group [1.60(0.48, 8.15) ng/ml vs 7.38(2.15, 19.02) ng/ml, P﹤0.01]. The level of urinary sPD-1 in onset group was higher than that in remission group [1.21(0.61, 2.56) pg/μg vs 0.51(0.31, 0.97) pg/μg, P﹤0.001] and healthy control group [1.21(0.61, 2.56) pg/μg vs 0.82(0.34, 1.15) pg/μg, P﹤0.01]. The levels of sPD-L1 in serum and urine were higher in onset and remission group than those in healthy control group (P﹤0.001). The level of sPD-1 in the serum was positive correlated with the numbers of CD3+, CD3+CD4+, CD3+ CD8+ T lymphocytes and CD3-CD19+, CD19+CD23+ B lymphocytes (r=0.537, 0.478, 0.454, 0.429 and 0.374; P=0.002, 0.008, 0.012, 0.018 and 0.042). The level of sPD-1 in the urine had positive relation with the ratio of 24 hours urinary albumin and weight (24 h UmAlb/Wt), N-acetylglucosaminidase and urinary creatinine (UNAG/Cr) and β2 microglobulin and urinary creatinine (Uβ2MG/Cr) (r=0.409, 0.588 and 0.276; P=0.016, 0.000 and 0.032). Conclusions The dynamic changes of sPD-1 and sPD-L1 in serum and urine suggested that PD-1/PD-L1 signaling pathway is involved in the development process of childhood primary nephrotic syndrome.     

Clinicopathological correlations in nephrotic children with IgA nephropathy

Background. The prognostic significance of nephrotic syndrome (NS) in children with IgA nephropathy (IgAN) is unclear. Methods. NS was found in eight children with IgAN (mean onset age, 9.3 years). The clinicopathological findings of these eight children were investigated. Results. Five patients presented with macroscopic hematuria, while the remaining three were discovered in a school urinary screening program or by chance urinalysis. Six patients developed NS at the onset, and two developed NS later in the course of IgAN. All patients were treated with corticosteroids. At the end of follow-up, heavy proteinuria persisted in four children, one of whom had renal dysfunction at the onset of NS and developed end-stage renal failure, and two of whom developed NS after the onset of IgAN. Proteinuria decreased to less than 1 g/day 3 months after NS in four patients, two of whom showed disappearance of proteinuria afterward. Renal biopsy specimens revealed mesangial proliferation and crescent formation in all patients. The degree of persisting proteinuria was correlated with the presence of glomerular sclerosis, fibrous crescents, tubulo-interstitial changes on light microscopy, and depositions of C3 on immunofluorescence microscopy. Conclusions. Children who developed NS after the onset of IgAN developed renal dysfunction; the prognosis of those who showed chronic histopathological changes on renal biopsy specimens was poor, even in these young children. Received: April 17, 2000 / Accepted: July 4, 2000     

NPHS2 (podicin) mutations in Turkish children with idiopathic nephrotic syndrome

The podocin (NPHS2) gene encodes podocin protein, which has an important role in glomerular ultrafiltration and controlling slit membrane permeability. The detection of an NPHS2 mutation affects the treatment plan for children with nephritic syndrome (NS). The frequency and spectrum of podocin mutations in the Turkish population have remained largely unknown. The aim of this study was to screen for podocin mutations in Turkish patients with steroid-resistant NS (SRNS) and to compare it with other published series. There were 295 children with SRNS, originating from Turkey, included in this study. Forty-one patients (13.8%) had familial NS and 254 patients (86.2%) had sporadic NS. Mutation analysis was performed in all eight exons of the NPHS2 gene with the direct DNA sequencing method. There were 53 different pathogenetic NPHS2 mutations detected, including 37 novel mutations. The mutation detection rate was 24.7% for all patients, 29.2% for familial, and 24% for sporadic SRNS. The most common mutated exon was exon 5 (52 allele). The presence of mutations in exon 4 was found to increase the risk of end-stage renal disease (ESRD). Among patients with mutations, the rates of renal failure and/or ESRD (26%) were significantly higher than in those without mutations (12.6%). The mean time of progression to renal failure and ESRD in patients with mutations (1.8 ± 2.5 years) was significantly shorter than in patients without mutations (3.7 ± 4.0 years). Additionally, in patients with heterozygote mutations, fewer cases (13.6%) progressed to renal failure and/or ESRD than in with patients who had homozygote/compound heterozygote mutations (31.3%). In conclusion, podocin mutations are responsible for some of both familial and sporadic SRNS cases in Turkey. The mutations in this gene should be searched for in every child after presentation with the first episode of NS.     

Glycosaminoglycan excretion in children with nephrotic syndrome

Although most childhood nephrotic syndromes respond to steroid treatment, steroid resistant nephrotic syndrome (SRNS) is also common and is particularly difficult to treat. This study investigated the role of glycosaminoglycans (GAG) in the pathogenesis and clinical course of nephrotic syndrome in children. Thirty-four children (21 males and 13 females, mean age 3.7±1.6 years) with steroid-sensitive nephrotic syndrome and 20 children with steroid-resistant nephrotic syndrome (12 males and 8 females, mean age 10.9±3.8 years; of the twenty, four had primary SRNS (FSGS) and the others had secondary SRNS) were included the study. Mean urine levels of GAG relative to creatinine (U_GAG/U_Cr) in patients with SRNS (n=20, 113.01±78.46 mg g^–1 Cr) and in patients experiencing the nephrotic period of steroid-sensitive nephrotic syndrome (n=34, 132.15±101.55 mg g^–1 Cr) were both significantly higher than mean U_GAG/U_Cr for control subjects (n=30, 51.83±47.66 mg g^–1 Cr) (P<0.01 for both). Patients excreted significantly more GAG during the nephrotic period of steroid-sensitive nephrotic syndrome than during remission (132.15±101.55 vs 39.11±42.73 mg g^–1 Cr, respectively; P<0.01). There was, however, no significant difference between U_GAG/U_Cr for patients with steroid-resistant nephrotic syndrome and U_GAG/U_Cr in the nephrotic period of steroid-sensitive nephrotic syndrome. Urine GAG excretion correlated significantly with the severity of proteinuria. The results suggest that GAG play a significant role in the pathogenesis of nephrotic syndrome but that GAG excretion is not a marker for response to steroid treatment in pediatric patients with this condition.     

中国南方汉族散发性激素耐药型肾病综合征儿童NPHS1基因突变分析

目的 研究我国南方汉族散发性激素耐药型肾病综合征(SRNS)儿童NPHS1基 因突变情况.方法 对象为40例南方汉族散发性SRNS儿童,50例尿检正常的汉族健康成年人作为对照.取受检者外周静脉血3ml,10％枸橼酸钠抗凝,提取基因组DNA.应用PCR方法扩增NPHS1基因全部29个外显子及其周围的部分内含子,对PCR产物直接进行DNA序列测定及突变分析.结果 6例存在NPHS1基因突变-928G ＞A (D310N)、2677A ＞G( T893A)、2869G＞C( V957L)、IVS8+30C＞T、IVS21+ 14G＞A、IVS25-23C ＞T和*142T＞C,突变检出率为15％.在50例健康对照人群中未检测出这7个变异,其中2677A ＞G、IVS8 +30C ＞T、IVS21+ 14G＞A、IVS25-23C＞T和*142T＞C为新发现NPHS1基因突变.此外,还确定了13个已报道的NPHS1基因多态性-294C ＞T、349G ＞A、IVS3+ 15C ＞T、IVS3 +61A ＞G、803G ＞A、IVS8+68A ＞G、1339G ＞A、1802G ＞C、2223C ＞T、2289C ＞T、IVS24 +36C ＞T、3315G＞A和IVS27 +45C ＞T.结论 在40例南方汉族散发性SRNS患儿中,NPHS1基因突变检出率为15％,提示南方汉族散发性SRNS患儿存在NPHS1基因突变,对这类患儿需进行NPHS1基因突变分析.