Vesico-ureteric reflux and other risk factors for renal damage: identification of high- and low-risk children

This article reviews the literature with respect to various risk factors for permanent renal damage in children with urinary tract infection. Vesico-ureteric reflux is an important risk factor, but renal damage can occur in the absence of reflux. Renal damage does not always occur in the presence of gross reflux. Renal scars always develop at the same site as a previous infection in the kidney. Recurrent pyelonephritis and delay in therapy increase the likelihood of renal damage, although it is not known how long a delay is dangerous to the human kidney. Recent studies using ^99mtechnetium-dimercaptosuccinic acid (DMSA) scintigraphy have not confirmed the findings of previous studies showing that children below 1 y of age are more vulnerable to renal damage. It is more likely that all children run the risk of renal scarring in cases of acute pyelonephritis. The role of bladder pressure is still not entirely understood. Therefore more studies are needed in order to determine the relationship between high voiding pressures in some, otherwise healthy, children with urinary tract infection and renal scarring. The importance of bacterial virulence in the development of renal scarring is unclear. DMSA scintigraphy and voiding cystourethrography are the most reliable tools for identifying children at risk of renal scarring. As a single method DMSA scintigraphy appears to be better than voiding cystourethrography.     

Vesico-ureteric reflux: occurrence and long-term risks

The prevalence of vesico-ureteric reflux in the general population is unknown, but it is increased in risk groups, such as children with symptomatic urinary tract infection, schoolgirls with asymptomatic bacteriuria, first-degree relatives of patients with reflux and children with prenatal dilatation of their upper urinary tract. Children and adults with pyelonephritic renal scarring are at risk of serious long-term complications, e.g. hypertension and renal failure. Modern paediatric care, with early detection and treatment of urinary tract infections and reflux during childhood and adolescence, may improve long-term prognosis. In the adult patient with established pyelonephritic renal scarring, careful control of hypertension may retard the rate of progression, and angiotensin converting enzyme inhibitors may have renal protective properties.     

Vesico-ureteric reflux: occurrence and long-term risks

The prevalence of vesico-ureteric reflux in the general population is unknown, but it is increased in risk groups, such as children with symptomatic urinary tract infection, schoolgirls with asymptomatic bacteriuria, first-degree relatives of patients with reflux and children with prenatal dilatation of their upper urinary tract. Children and adults with pyelonephritic renal scarring are at risk of serious long-term complications, e.g. hypertension and renal failure. Modern paediatric care, with early detection and treatment of urinary tract infections and reflux during childhood and adolescence, may improve long-term prognosis. In the adult patient with established pyelonephritic renal scarring, careful control of hypertension may retard the rate of progression, and angiotensin converting enzyme inhibitors may have renal protective properties.     

环境有害因素与儿童肾损害

环境有害因素通过多途径侵入人体,其中以食入、吸入、皮肤和黏膜接触吸收为主。它的来源多样化,其中土壤、水源、空气、建筑装修材料、食品、日用品为其主要载体。按照其理化特性及形态特性分为金属类、无机物、有机物、放射性物质、生物毒素、病毒、细菌、支原体、衣原体和寄生虫。发病机制主要通过血液和尿液作用于肾组织,同时有肾易感性。本文提示儿科医师应该充分认清环境有害因素致肾损害的特性和严峻性,重视防治工作,才能最大程度减少儿童肾损害。     

Long-term renal risk factors in children with meningomyelocele

We studied renal function and structure in 42 patients with meningomyelocele, 28 treated with intermittent catheterization and 14 with ileal loop diversion. Patients were observed for a minimum of 60 months. Nine of the 28 patients who underwent intermittent catheterization had evidence of unilateral or bilateral reflux, and all patients with ileal loop diversion had free ureteral reflux. Bacteriuria was present in 38% +/- 5% of cultures obtained from patients with catheterization and in 70% +/- 7% of cultures from those with diversion (P less than 0.001). Four (14%) of 28 patients with catheterization had worsening renal function or anatomic appearance by intravenous pyelogram, and required a diversion. Three (28%) of 14 patients with diversion had changes in renal structure or function. Eight of 31 patients from both groups studied with voiding cystourethrography before the onset of therapy had small, noncompliant, trabeculated bladders; all seven patients who had worsening in function or anatomic appearance were from this subset (P less than 0.01). None of the patients with flaccid or distensible bladders demonstrated these changes. Renal disease was unrelated to the level of neurologic function. A small, noncompliant, trabeculated bladder is a risk factor associated with loss of renal function in patients with meningomyelocele.     

Unilateral vesicoureteric reflux: Low prevalence of contralateral renal damage

OBJECTIVE: We assessed the risk for the occurrence of renal damage in children with vesicoureteric reflux (VUR). STUDY DESIGN: We reviewed the records of 187 consecutive children, aged 3.8 +/- (SD) 2.8 years, with unilateral primary VUR diagnosed after urinary tract infection (UTI). Dimercaptosuccinic acid renal scintigraphy was performed 4 to 6 months after the last UTI. Three patterns of renal damage were identified: global reduction (GR) of renal radionuclide uptake (20% to 40% of relative uptake), focal defects (FD) in uptake, and shrunken (relative uptake <20%) kidney (SK). We assumed that in these subjects FD indicated postpyelonephritic damage and that GR indicated congenital renal damage. RESULTS: Scintigraphic renal damage of any type was present in 36.9% of the refluxing and in 3.2% of the nonrefluxing kidneys (odds ratio [OR], 17.6; 95% CI, 7.4 to 41.9). FD were present in 15.5% and 2.7% (OR, 6.7; CI, 2.5-17.6), GR in 19% and 0.5% (OR, 44.3; CI, 6.1 to 327.2), and SK in 6.9% and 0%, respectively. Patients with severe VUR showed a higher probability of renal damage than those with nonsevere VUR. CONCLUSIONS: In children with UTI and VUR, the refluxing kidney is most at risk of both congenital and acquired renal damage, and this risk increases with severity of reflux.     

Sociodemographic risk factors for sudden infant death syndrome: associations with other risk factors

The aim of this study was to investigate associations between sudden infant death syndrome (SIDS) and social factors in the Nordic countries. A case-control study was conducted in Denmark, Norway and Sweden: The Nordic Epidemiological SIDS Study. Parents of 244 SIDS infants and 869 control infants matched on gender, age at death and place of birth filled in questionnaires. The dataset was analysed by conditional logistic regression. In univariate analysis, the following sociodemographic factors were associated with an increased risk of SIDS: low maternal age [odds ratio (OR) 7.8; 2.8-21.5], high birth order (OR 4.4; 2.5-7.5), single motherhood (OR 2.9; 1.7-5.0), low maternal education (OR 4.5; 2.8-7.1), low paternal education (OR 3.0; 1.9-4.7), maternal unemployment (OR 2.4; 1.8-3.4) and paternal unemployment (OR 4.0; 2.7-5.9). In a multivariate analysis where maternal smoking was also included, only paternal unemployment, young maternal age and high birth order remained significantly associated with SIDS. Housing conditions were not associated with SIDS. However, the risk of SIDS was high if the family had lived in their present home for only a few years (OR 2.3; 1.3-4.1). Sociodemographic differences remain a major concern in SIDS in a low-incidence situation and even in an affluent population with adequate health services.     

Vesicoureteric reflux and renal scars in asymptomatic siblings of children with reflux.

The purpose of the study was to determine the incidence of vesicoureteric reflux (VUR), renal scars and hypertension in asymptomatic siblings of children with VUR. The study comprised 105 siblings of patients with VUR. Their age ranged from 4 months to 6.3 years. All had a direct radionuclide voiding cystography (DRVC) performed, and VUR was detected in 47 of 105 (45%). High grade VUR in the first year of life had an incidence of 50% compared with a 9% incidence in siblings older than 2 years, while only one of the 27 siblings with a low VUR grade was younger than 1 year. In 43 of 47 siblings with VUR, a technetium-99m dimercaptosuccinic acid (99mTc-DMSA) scan was performed and renal scars were found in 10, which presents 23% of siblings with VUR who were scanned and 10% of all siblings studied. One child had hypertension. Identifying VUR among asymptomatic siblings could possibly prevent renal damage and its consequences. Thus, the predictive value of positive family history alone in identifying VUR was 45% while 23% of siblings had renal scars. This incidence justifies the routine investigation of asymptomatic siblings, by using DRVC at an early stage.     

Maternal risk factors for fetal and neonatal brain damage

Prematurity is probably the major factor associated with brain damage in newborns. Our growing knowledge of the biochemical mechanisms leading to the onset of labour at term allows the biochemical correlates of the epidemiological risk factors for prematurity to be understood. Infection is the major cause of early preterm labour and is now recognised to be a major cause of fetal cerebral damage leading to cerebral palsy. Only some 5% of cerebral palsy is due to intrapartum asphyxia at term. This may occur due to an obstetric catastrophe or through inadequate placental function leading to chronic intrapartum asphyxia.     

高渗及低渗造影剂对儿童肾脏功能影响的临床研究

目的初步探讨高渗及低渗造影剂对儿童肾脏功能的影响,以及水化对造影剂相关性肾病(CAN)的预防作用。方法将行静脉肾盂造影或增强CT检查的患儿分为高渗造影剂组(HOCM)27例和低渗造影剂组(LOCM)33例,各组患儿随机分为水化组和非水化组。水化组于造影后立即给予1/5张含钠维持液20ml/kg于3h内静脉滴入,非水化组不给予静脉补液。结果(1)HOCM组造影前,非水化组与水化组相比,SCr、Ccr差异均无统计学意义。造影后,HOCM非水化组SCr[(59·71±12·49)μmol/L]较造影前[(49·91±6·09)μmol/L]显著增高(P<0·05),而Ccr造影后[(71·33±7·51)ml/(min·1·73m2)]较造影前[(97·81±15·10)ml/(min·1·73m2)]明显降低(P<0·05);HOCM水化组SCr、Ccr在造影前、后差异无统计学意义(P>0·05)。HOCM非水化组有3例(23·1%,3/13)发生CAN,HOCM水化组无1例发生CAN(P>0·05)。(2)LOCM水化和非水化组造影前、后SCr、Ccr差异均无统计学意义。LOCM非水化组CAN发生率为6·7%(1/15),LOCM水化组11·1%(2/18)(P>0·05)。(3)HOCM非水化组与LOCM非水化组相比,造影后SCr显著升高(Z=-2·42,P<0·05),而Ccr降低(Z=-2·83,P<0·05)。(4)HOCM与LOCM组共计6例CAN在2周内SCr及Ccr恢复至造影前水平。结论(1)肾功能正常的儿童应用高渗或低渗造影剂均可发生可逆的造影剂肾病;(2)高渗造影剂对儿童血肌酐及肌酐清除率的影响大于低渗造影剂;(3)水化可减轻高渗造影剂对儿童肾脏功能的损害;(4)儿童应用低渗造影剂水化后仍可发生CAN。     

A multi-institutional retrospective study of intracranial ependymoma in children: identification of risk factors.

PURPOSE: The goal of this multi-institutional retrospective study of children with intracranial ependymoma was to identify risk factors associated with unfavorable overall survival (OS) and event-free survival (EFS). PATIENTS AND METHODS: Clinical data, including demographics, tumor location, spread, histology, details of surgery, radiation treatment, and chemotherapy were collected. Clinical characteristics and univariate and multivariate analyses of risk factors for OS and EFS are presented. RESULTS: Eleven U.S. institutions contributed 83 patients treated from 1987 to 1991. The OS at 5 and 7 years was 57% and 46%, and EFS at 5 and 7 years was 42% and 33%. Patients 3 years of age or younger differed from the older group by more common infratentorial location, less common gross total resection (GTR), and postoperative use of chemotherapy rather than radiation. This younger group of patients had worse survival (P < 0.01) than the older age group. Other than young age, less than GTR and World Health Organization (WHO) II grade 3 histology were significant adverse risk factors for EFS in univariate and multivariate analyses. OS shared the same adverse risk factors except for histology in multivariate analysis, which was only of borderline significance (P = 0.05). Progression at the original tumor location, present in 89% of patients, was the major pattern of tumor recurrence. Adjuvant chemotherapy in the group older than 3 years or craniospinal radiation in M0 patients did not significantly change EFS. CONCLUSIONS: Adverse outcome in childhood intracranial ependymoma is related to age (3 years or younger), histology (grade 3), and degree of surgical resection (less than GTR). New approaches, particularly for local tumor control in younger patients, are needed to improve survival.     

Echocardiographic changes and risk factors for left ventricular hypertrophy in children and adolescents after renal transplantation

Long-term consequences of cardiac alteration in children with chronic renal failure and after renal transplantation are largely unknown. In chronic uremia, cardiomyopathy manifests itself as systolic dysfunction, concentric left ventricular hypertrophy (LVH) or left ventricular dilatation. The correction of uremic state by renal transplantation leads to normalization of left ventricular contractility, regression of LVH and improvement of cavity volume and so dialysis patients with uremic cardiomyopathy would benefit from renal transplantation. We studied 73 patients, aged 17 yr or less, who underwent renal transplantation in our center. This cross-sectional study was performed 4.6 yr (median) after transplantation. Of the total, 48 were males and 25 were females. Transthoracic echocardiographic examination was performed for all cases. The effects of clinical, demographic, biochemical and therapeutic data on echocardiographic parameters were assessed. Multivariate analysis was used to assess the relation between the risk factors and the left ventricular muscle mass index. The most common echocardiographic abnormalities were the LVH (47.9%), left atrial enlargement (31.5%) and left ventricular dilatation and systolic dysfunction (13.7% for each). The pretransplant dialysis, arteriovenous fistula, acute rejection, cumulative steroid dose per square meter surface area, post-transplant hypertension, anemia and graft dysfunction were significant risk factors for LVH by univariate analysis. The significant factors by multivariate analysis were pretransplant dialysis, post-transplant hypertension and anemia. From this study we may conclude that LVH is a common problem among renal transplant children and adolescents. Early transplantation, control of hypertension and correction of anemia may be beneficial regarding left ventricular function and structure.     

儿童肾瘢痕形成的危险因素

肾瘢痕可导致高血压、蛋白尿、慢性肾脏病、甚至终末期肾病的可能。研究儿童肾瘢痕形成的危险因素,有利于早发现、早诊断、早预防、早治疗。高级别的膀胱输尿管反流,反复的泌尿道感染,以及延误治疗都是肾瘢痕形成的危险因素。但是仍有一些因素,如性别和年龄,先天性因素与肾瘢痕的关系目前仍存在争议。近年研究发现,尿液无创指标,如尿中性粒细胞明胶酶相关脂质运载蛋白、尿内皮素-1及风险预测模型均可预测肾瘢痕的形成,而预防应用抗生素虽可减少泌尿道感染的发生,但并不能降低肾瘢痕形成的风险。文章综述了儿童肾瘢痕形成的可能危险因素和预测指标,为临床对肾瘢痕的早期发现、及时干预和有效预防提供依据,以期减少肾瘢痕的形成和进展。