The impact of perinatal urinoma formation on renal function: our experience and review of the literature

Introduction: A urinoma is a fluid mass consisting of extravasated urine in the perirenal space. Its impact on renal function was analysed. Methods: All cases of prenatal and neonatal urinoma reported in the literature were analysed as well as two cases recently observed in our department. Results: A review of all prenatally diagnosed urinomas revealed 25 cases, for a total of 30 renal units. The cause of obstruction was: lower urinary tract (LUT) obstruction in 16 cases (62.5%), upper urinary tract (UUT) obstruction in seven cases (29.5%) and unknown in two cases (8%). A preserved renal function was found in only 30% of all cases. Furthermore, prognosis for renal function was better in posterior urethral valve (PUV) patients than in uretero‐pelvic junction obstruction (UPJO) patients. In addition, we analysed 35 published cases of urinoma with a neonatal onset, without prenatal diagnosis, and secondary to LUT obstruction in 27 cases (77%), UUT obstruction in seven cases (20%), while the underlying cause was unknown in one cases (3%). A preserved renal function was observed in 84% of cases with UUT obstruction and in 80% of cases presenting a LUT obstruction. Conclusions: Prognosis concerning renal function seems to be mainly related to two factors: age at presentation and underlying diagnosis. Decompression of the urinary tract by urine extravasation produces the best results in terms of preservation of the renal function in LUT obstruction (75% in prenatal and 84% in postnatal cases); UUT obstruction however is associated with a good prognosis in the neonatal period (80% of preserved renal function) but with a severe impairment (only 20% of preserved renal function) in prenatally detected cases.     

Cystic Dysplasia of the Testis: A Report of Three Cases and Review of the Literature

We describe the clinical and pathologic findings in three cases of cystic dysplasia of the testis and compare our findings to others in the English literature. The condition is characterized by dilatation of the rete testis with or without similarly affected adjacent structures. It is important to recognize this lesion for two reasons. First, it is associated with a high frequency of ipsilateral renal anomalies. Second, it is important to consider this condition in the differential diagnosis of cystic testicular mass in a neonate or a child. The management of this condition is quite different from the management of other testicular masses such as a hydrocele, testicular germ cell tumor, or infiltrative disorder (e.g., lymphoma, inflammation, torsion, or hematoma). Testicular cystic dysplasia is benign and the lesion can be removed surgically, leaving the rest of the testis intact. A discussion of the lesion's possible pathogenesis is also presented.     

Imaging of renal scarring

Children with urinary tract infection should be investigated and followed up, as those with pyelonephritis may develop renal scarring. In this review, after discussing the advantages and disadvantages of various imaging modalities for diagnosis of renal scarring, it is concluded that DMSA scintigraphy and urography can both be used to detect significant renal scarring. With DMSA scintigraphy, small renal lesions (functional uptake defects) not seen at urography will also be detected. The long-term clinical significance of these lesions is, as yet, unknown. A normal DMSA scintigraphy after infection indicates low risk for clinically significant damage. In order to allow acute, reversible lesions to first disappear, a follow-up DMSA examination should not be performed until at least 6 mo after the acute infection. Ultrasonography in isolation cannot be recommended for the diagnosis of renal scarring.     

Novel alternative splicing of human faciogenital dysplasia 1 gene

The human faciogenital dysplasia 1 (FGD1) gene product plays an important role in morphogenesis. Its dysfunction causes Aarskog-Scott syndrome (MIM musical sharp 305400). To characterize the FGD1, we investigated its expression by RT-PCR and Southern blot analysis in normal tissues. We found novel alternative forms of the FGD1. One has a novel exon located in intron 8, named exon 8B (8B FDG1) and the other has an exon in intron 7, exon 7B (7B FGD1). The 8B FDG1 is expressed strongly in the brain, testis, spinal cord, trachea and stomach, and weakly in the thymus and lymphocytes. However, expression of the 7B FGD1 is weak and restricted in the testis and salivary gland. Insertion of each novel exon results in production of a premature termination codon, respectively, and the predicted proteins generated from them have only a proline-rich domain and an incomplete DH domain which potentially compete with the wild type of FGD1.     

Paediatric renal stone disease: investigation and management for the paediatrician

Paediatric renal stone disease is uncommon but its incidence is increasing. There has been a shift from predominantly infective stones to a higher rate of metabolic stones. It may present with non-specific symptoms of abdominal pain, haematuria, recurrent urinary tract infections, or may even be found incidentally. Ultrasound scanning should be the first line of imaging in children with suspected renal calculi. If detected, this should be followed by a thorough investigation of underlying causes with blood and urinary analyses to investigate metabolic causes, and further imaging to detect anatomical anomalies and for surgical planning, if required. Acute management consists primarily of good analgesia, hydration and management of sepsis, if present. Surgery may rarely be indicated in an obstructed system. There is a range of surgical options for the definitive management of renal calculi. The selection of a particular treatment modality is dependent on multiple factors. Renal calculi can recur and cause co-morbidities including renal impairment leading to the need for renal replacement therapy. Therefore, patients should be managed proactively. This short article outlines what paediatricians and healthcare professionals caring for children need to know about the diagnosis, management and appropriate referral onwards of children with renal stone disease.     

Renal-hepatic-pancreatic dysplasia: An autosomal recessive disorder with renal and hepatic failure

Abstract We report two brothers with renal dysplasia and congenital hepatic fibrosis. One patient died shortly after birth of lung hypoplasia. The second developed end-stage renal failure at 14 months. The hepatic fibrosis progressed to cirrhosis and hepatic failure. Pancreatic function was normal, but increased echogenicity was seen on ultrasound. At age 3 years and 9 months a successful combined liver-kidney transplantation was performed. The features of our patients are compatible with the renal-hepatic-pancreatic dysplasia syndrome.Conclusion Renal-hepatic-pancreatic dysplasia is an autosomal recessive disorder with variable expression. Combined liver-kidney transplantation offers a new therapeutic option.     

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.     

Trends in the health burden due to urinary tract infection in children in Australia

Objective: To estimate the health burden of urinary tract infection in children less than 15 years of age in Australia and to ascertain whether any significant change has occurred during the past decade. Methodology: The number of children less than 15 years of age who were admitted in New South Wales for urinary tract infection between 1981 and 1994 was ascertained from the Department of Health, and age and sex specific incidence rates were calculated using Australian Bureau of Statistics population data. Costs for inpatient care were calculated using the cost weights from Australia National Disease Related Groups Version 3 for urinary tract infection (DRG 577). The frequency of the four most commonly requested renal tract imaging procedures in children following urinary tract infection and which qualified for Medicare reimbursement were obtained from the Health Insurance Commission for 1984–1994: micturating cystourethrography, intravenous urography, renal ultrasonography, and nuclear medicine renal studies. Results: There were 1203 children who were admitted with urinary tract infection in New South Wales in 1994, at an estimated cost of $A1.6 million. Since 1981, the age standardized annual incidence of urinary tract infection requiring hospitalization has increased from 0.5 to 0.9 per 1000 children, largely because of an increase in the number of young children admitted (from 0.6 to 2.0 per 1000 children less than 5 years of age). In 1994, 46 230 non-inpatient renal imaging procedures were undertaken in children under 15 years of age at a cost of $A5.3 million. Conclusions: Urinary tract infection is an important and increasing health problem for Australian children, particularly for preschool children. Whether this represents a true increase in the incidence of urinary tract infection or improved diagnosis and more intensive management is not possible to establish with this study design. Prospective population based studies are required to assess more completely the frequency with which urinary tract infection occurs in children and any changes that may be occurring.     

Molecular Mechanisms of Human Embryogenesis: Developmental Pathogenesis of Renal Tract Malformations

The focus of this review is the normal and abnormal development of the kidney and lower urinary tract; for convenience, we will refer to the whole system as the renal tract. The content represents a convergence among the clinical disciplines of histopathology, nephrology, and urology as well the basic sciences of developmental biology and molecular genetics. The story has considerable clinical relevance since diverse renal tract malformations are increasingly detected on fetal ultrasound screening and constitute major causes of chronic renal failure necessitating dialysis and kidney transplantation in children. Evidence is emerging that at least some of these disorders have a defined genetic basis; in others, an abnormal embryonic, or even maternal, environment may contribute to the pathogenesis. This field of study is frequently updated, with new discoveries being made almost every week. Hence this review can not be exhaustive or definitive, but instead highlights some specific areas of interest. Received July 1, 2001; accepted September 1, 2001.     

Evaluation and treatment of chronic renal failure

Chronic renal failure (CRF) is the irreversible deterioration of renal function that gradually progresses to end stage renal disease (ESRD). The chief causes of CRF include obstructive uropathy, primary glomerular diseases, reflux nephropathy and hypoplastic or dysplastic kidneys. Progressive hyperperfusion and hyperfiltration causes increasing glomerular injury and further renal damage. Symptoms of CRF are usually seen when GFR is between 10–25% of normal. Children with severe CRF often suffer from failure to thrive, growth retardation, acidosis, anemia and renal osteodystrophy. Management of CRF aims at retarding progression of renal damage and treatment of complications related to renal dysfunction. Measures suggested to retard progression include protein restriction, strict control of hypertension, use of angiotensin converting enzyme inhibitors and control of hyperlipidemia. Appropriate amounts of protein and calories are recommended to prevent growth failure. Nutritional supplements are often required. The availability of recombinant erythropoietin, calcitriol and human growth hormone has significantly improved the management of these patients. Once ESRD supervenes, renal replacement therapy in the form of chronic peritoneal or hemodialysis and transplantation is necessary.     

Renal dysplasia: An autopsy study of associated congential malformations

A retrospective analysis of infant autopsies in the last 14 years was done with the aim of determining the frequency of associated malformations. Renal dysplasia comprised 36 of 594 autopsies done and was the commonest congenital urologic malformation (6.06% of all infant autopsies). Histologically all cases were characterised by hallmarks of disordered metanephric differentiation and organisation. Extrarenal malformations were seen in all (100%) of the cases of which other urologic anomalies were the commonest (28) followed by those of musculoskeletal (18), gastrointestinal (13), cardiovascular (10) and central nervous system (6). Syndromic association was seen in 5 (14%) cases. There were twenty two percent still births and 47% infants died perinatally. A thorough search for systemic malformations is mandatory in all cases of renal dysplasia as these may influence the survival significantly. Cystic renal dysplasia should be differentiated from other causes of cystic renal diseases.     

Neurofibromatosis involving the lower urinary tract in children A report of three cases and a review of the literature

Three children with neurofibromatosis involving the lower urinary tract are reported and their clinical, radiological and pathological findings are described. Lower urinary tract involvement in neurofibromatosis has previously been reported in 17 children, 12 of whom had other stigmata of von Recklinghausens disease. Lower urinary tract involvement may be asymptomatic and can be found incidentally. Every case with neurofibromatosis presenting with what may appear to be even only insignificant urinary symptoms should be thoroughly investigated urologically. Symptoms are usually related to urinary tract obstruction or neurogenic bladder dysfunction due to the involvement of the nerves supplying the bladder. Urinary diversion is the treatment of choice as surgical removal of the extensive tumour is seldom feasible. Following treatment the prognosis for survival appears to be good.     

The Urinary System in Down Syndrome: A Study of 124 Autopsy Cases

We examined 124 autopsy cases of Down syndrome for the presence of renal and urinary tract abnormalities. The cases were divided into three groups: (I) fetuses of 16-22 weeks gestation (n = 18), (II) stillborns or newborns who died on the first day of life (n = 9), and (III) Down patients 1 day to 25 years of age (n = 97). Kidney weight was reduced by a mean of 14.4% compared with expected values. Renal hypoplasia, defined as kidney weight less than two-thirds expected, was found in 18 cases. Glomerular microcysts were found in 23 of 97 cases in group III. Focal dilatation of tubules was found in 10, simple cysts in 7, and immature glomeruli deep in the renal cortex in 18 cases. Obstructive uropathy occurred in 2 of 18 (11.1%) in group I, 2 of 9 (22.2%) in group II, and 4 of 97 (4.1%) in group III. Obstructive uropathy with bilateral cystic dysplastic kidneys resulted in Potter's sequence. We suggest that obstructive uropathy is associated with Down syndrome. When severe, it results in Potter's sequence and an early perinatal death. A chromosomal analysis is recommended in any case of obstructive uropathy in the fetal or neonatal period.     

Multicystic kidney dysplasia: a prospective study on the natural history of the affected and the contralateral kidney

In a 6-year period, 41 young infants with multicystic kidney dysplasia were seen in our department. In 30 cases, the diagnosis had already been suspected by prenatal ultrasonography. A prospective protocol was proposed to the parents which comprised ultrasound evaluation every 3 months until the age of 24 months and renal function assessment at the age of 18 months. In 33 patients, the study was completed as scheduled. At the start of the study, the maximal diameter of the multicystic kidney was above the mean length of normal kidneys in all cases where precise measurement was possible. Within 24 months, 7 of the dysplastic kidneys disappeared, 20 regressed in size, 1 remained unchanged and only 5 increased in size. Between the age of 0 to 3 months, renal length of the contralateral kidney was within the normal range in 19 infants and above +2SD in 14 cases. At the age of 18 to 24 months, renal length was, with few exceptions, between 0 and +4SD. Inulin clearance was normal in all 33 individuals with a median value of 112 ml/min per 1.73 m². Conclusion As a rule, multicystic kidneys shrink in the first 2 years of life. In most cases the contralateral kidney maintains a normal renal function as a consequence of progressive compensatory hypertrophy. Received: 19 November 1997 / Accepted in revised form: 31 January 1998     

Diagnostic imaging in children with urinary tract infection: the role of intravenous urography

Ninety children referred to hospital with urinary tract infection (UTI) were investigated by iv urography (IVU), ultrasonography (US) and ^99mTc dimercaptosuccinic acid scan (DMSA). Fifty-eight children also underwent micturating cystourethrography (MCUG). In 36 (40%) of the children, at least one result was abnormal. Abnormal findings were found in 29 children with IVU, in 10 with US and in 16 with DMSA. Six of the 58 children had vesicoureteric reflux (VUR) in 8 kidneys. In 16 children, IVU was the only examination with an abnormal result, and in 10 of these the findings were considered important for treatment or prognosis. IVU is an important supplement to US and DMSA in investigation programs for children with UTI. IVU should be performed in cases of renal scars, dilatations or in children with recurrent infections.     

A case of skeletal dysplasia with advanced carpal ossification and “monkey wrench” appearance of the femora: mild Desbuquois dysplasia?

Abstract We report on a 14-year-old Japanese boy with radiographic features resembling those of Desbuquois dysplasia, including advanced carpal ossification, a “monkey wrench” appearance of the proximal femora, mild spondylar dysplasia, and generalized osteopenia. In contrast to the hitherto known patients with this disorder, however, his birth length was normal, and his short stature, which became apparent postnatally, was much milder than that of the previously reported cases (approximately −5 SD of average) and the joint laxity was more subtle. In addition, facial dysmorphism was absent, as were radial deviation of the second fingers and thoracolumbar kyphoscoliosis. Conclusion The present patient may represent the mildest end of the variable phenotypic manifestation of the recently described Desbuquois dysplasia     

Evaluation of lower urinary tract dysfunction in Turkish primary schoolchildren: An epidemiological study

ObjectiveThe aim was to determine the prevalence of voiding dysfunction and its related risk factors in Turkish schoolchildren.Materials and methodsA randomly selected, cross-sectional study was conducted using a self-administered and previously validated questionnaire. The questionnaire consisted of two parts. The first part included personal demographic and familial information, and the second part included the Dysfunctional Voiding and Incontinence Scoring System (DVISS). The questionnaires were given to 4668 children between 6 and 15 years of age, which were completed by the parents and children together. The children with a score of ≥9 were accepted as having lower urinary tract dysfunction (LUTD).ResultsThe data were collected from 4016 children (the response rate was 86.0%), including 48.6% boys and 51.4% girls. The mean age was 10.5 ± 2.2 years. The overall frequency of LUTD was 9.3%. While the 6-year-old children had the highest frequency (23.1%) of LUTD, this rate was 7.9% at the age of 10, and the children aged 14 years had the lowest frequency (4.9%), (p < 0.001). Lower urinary tract symptoms were significantly more common in girls (7.6%) than in boys (3.2%) only for the older age group (between 12 and 15 years of age). Compared with normal children, those with LUTD (with a score of ≥9) had the following risk factors: less educated parents, a parent that had lower urinary tract symptoms when he or she was a child, more persons per room (≥2 persons), more siblings (≥4 siblings) at home, past medical history of urinary tract infections, and squatting position (in girls).ConclusionsLower urinary tract problems are one of the most important and ongoing health problems in childhood. Determining the prevalence of lower urinary tract problems in children and their related risk factors is the first step to managing and reducing the number of children suffering from voiding problems.