Congenital solitary kidney. A review of 74 cases

Herlyn-Werner-Wunderlich syndrome: A report of three cases in adolescents and adult woman

We report three cases with Herlyn-Werner-Wunderlich syndrome in adolescents and young female. The objective of this report was to describe the clinical presentation, ultrasound (US) and magnetic resonance imaging (MRI) findings of Herlyn-Werner-Wunderlich syndrome. The three patients were 12, 13 and 34 years old, respectively. The reason for admission and clinical symptoms varied between the 3 patients, including menstrual cramps, vaginal bleeding, and dull pain in the hypogastric region. Nevertheless, the sonographic and MRI findings of all three cases were typical for HWWS, including didelphys uterus, obstructed hemivagina, and ipsilateral renal agenesis.

Absent Ureteral Efflux after Hysterectomy Leads to Diagnosis of Ureteral Atresia with Renal Atrophy

Iatrogenic injury to the urinary system is a known complication of gynecologic surgery; therefore, intraoperative cystoscopy is frequently performed to assess for such injuries. However, if an abnormality is seen, the differential diagnosis extends beyond iatrogenic causes. A 42-year-old patient underwent a total abdominal hysterectomy and had absent efflux from the right ureteral orifice on cystoscopy. While iatrogenic injury was initially suspected, the intraoperative workup (including intravenous pyelography (IVP)) that ensued led to an empiric diagnosis of right ureteral atresia with ipsilateral renal atrophy that was then confirmed on postoperative imaging. When an abnormality is seen on cystoscopy following gynecologic surgery, it is important to maintain a broad differential diagnosis and to pursue an intraoperative workup with early involvement and close collaboration with urology.

Unilateral Hydronephrosis with Congenital Absence of Contralateral Kidney in Children

The case histories of six children with absence of functioning renal parenchyma on one side and dilatation of the contralateral pelvis are reviewed. The hydronephrosis was obstructive in two cases. In the others no cause could be found. The development of this combination of renal malformations is discussed against an embryologic background.

Unilateral anomalies of kidney development: why is left not right?

Abnormal renal development results in congenital anomalies of the kidney and urinary tract. As many studies suggest that renal malformations are more often found on the left side, a meta-analysis was performed on the distribution of five different unilateral anomalies: multicystic dysplastic kidney, renal agenesis/aplasia, renal ectopia, pelviureteral junction obstruction, and non-obstructive non-refluxing megaureter. Of these anomalies, the left side was affected in 53%, 57%, 56.9%, 63.2%, and 62.5% of patients, respectively, significantly different when compared with an anticipated 50% of left-sided anomalies. An exception to this left-side predominance was found in females with combined genital anomalies and unilateral renal agenesis that commonly present on the right side. The exact mechanisms leading to these lateralizations remain to be determined but may involve vascular development, differential gene expression, or susceptibility to environmental factors such as hypoxia. This remains largely speculative, however, illustrating our limited knowledge of embryogenesis in general and nephrogenesis in particular.

Associated urologic anomalies in children with solitary kidney

PURPOSE

The aim of this study was to investigate the incidence, nature, surgical treatment, and outcome of associated urologic anomalies (AUA) in children with anatomic or functional solitary kidney (SK).

METHODS

In this study, SK was defined as the kidney that is present in cases of unilateral renal agenesis (RA), or the kidney that is contralateral to a kidney that is nonfunctional secondary to either noncystic dysplastic kidney disease (NCDK), or multicystic dysplastic kidney disease (MCDK). Fifty-seven consecutive patients with SK (17 owing to RA, 10 owing to NCDK, 30 owing to MCDK) were reviewed.

RESULTS

A total of 23 of 57 (40%) had AUA in the SK (11 of 17 [65%] of RA cases; 7 of 10 [70%] of NCDK cases; and 5 of 30 [17%] of MCDK cases). The incidence of AUA in MCDK was significantly lower than that in RA or NCDK (p <.01: Mann-Whitney U test). Surgery was performed on 20 of 23 (87%) for vesicoureteric reflux (VUR) in 13, pelviureteric junction stenosis in 3, and ureterovesical junction stenosis in 4. Surgery was not performed in 3 of 16 with VUR because the VUR that was present was of low grade. AUA-related symptoms such as urinary tract infection and abdominal mass were seen in 15 of 23; the remaining 8 were asymptomatic. Mean age at surgery was 4.8 years. There were no operative or postoperative complications, and all cases are well without impaired renal function or hypertension after a mean follow-up period of 5.3 years.

CONCLUSIONS

In patients with SK, 40% had AUA in the renal collecting system of the SK. All children with SK should undergo a screening voiding cystourethrography (VCUG) even in the absence of hydronephrosis or UTI, and early recognition and treatment are imperative to decrease the long-term risk for renal damage.

Diagnosis of vesico-ureteric reflux

The demonstration and grading of reflux is crucial in examination and follow-up of any child with upper urinary tract infection. A variety of factors can influence the occurrence of reflux, e.g. race, genetics, state of maturation of the ureterovesical valve, diuresis, infection and bladder dysfunction, including obstruction and neurogenic disorders. Even when reflux is investigated under strictly standardized conditions, two consecutive bladder fillings frequently show different grades of reflux. Voiding cystourethrography is, to date, the only method with a generally accepted, well-defined grading of reflux. It also allows detection of intrarenal reflux and anatomical and functional information about the bladder and urethra that is unobtainable by other methods. It is therefore usually considered the method of choice. Radionuclide cystography and, possibly, contrast enhanced ultrasonography can be complementary to voiding cystourethrography, but mainly for postoperative follow-up and screening of siblings.

Associated urological anomalies in children with unilateral renal agenesis

PURPOSE

Unilateral renal agenesis has been noted in 1:1,000 autopsies. Recently an increased incidence of vesicoureteral reflux was reported in patients with a solitary kidney. We determined the incidence of associated renal abnormalities in children with unilateral renal agenesis.

MATERIALS AND METHODS

We retrospectively reviewed 46 consecutive cases of unilateral renal agenesis diagnosed at our hospital between January 1985 and February 1998. Patient age at diagnosis ranged from newborn to 12.5 years (mean 2.8 years). There were 24 boys and 22 girls. The left kidney was absent in 27 patients and the right kidney was absent in the remaining 19. A total of 24 patients were evaluated for urinary tract infection and in the other 22 a solitary kidney was found during examination for congenital malformations, enuresis or abdominal pain. The diagnosis was made in all patients by abdominal ultrasound and confirmed by excretory urography, or diethylenetriaminepentaacetic acid or dimercapto-succinic acid scan. A voiding cystourethrogram was performed in 40 patients (87%).

RESULTS

Associated urological anomalies were present in 22 of the 46 patients (48%) with unilateral renal agenesis, including primary vesicoureteral reflux in 13 (28%), ureterovesical junction obstruction in 5 (11%), ureteropelvic junction obstruction in 3 (7%), and ureterovesical and ureteropelvic junction obstruction in 1 (2%). Of the 22 patients 14 (64%) underwent surgical intervention.

CONCLUSIONS

Nearly half of the patients with unilateral renal agenesis had associated urological anomalies. Vesicoureteral reflux was the most common associated anomaly and it was usually of high grade. Early recognition and treatment of urological anomalies in a patient with a solitary kidney are imperative to decrease the long-term risk of renal damage.

Associated urological anomalies in children with unilateral renal agenesis

PURPOSE

Unilateral renal agenesis has been noted in 1:1,000 autopsies. Recently an increased incidence of vesicoureteral reflux was reported in patients with a solitary kidney. We determined the incidence of associated renal abnormalities in children with unilateral renal agenesis.

MATERIALS AND METHODS

We retrospectively reviewed 46 consecutive cases of unilateral renal agenesis diagnosed at our hospital between January 1985 and February 1998. Patient age at diagnosis ranged from newborn to 12.5 years (mean 2.8 years). There were 24 boys and 22 girls. The left kidney was absent in 27 patients and the right kidney was absent in the remaining 19. A total of 24 patients were evaluated for urinary tract infection and in the other 22 a solitary kidney was found during examination for congenital malformations, enuresis or abdominal pain. The diagnosis was made in all patients by abdominal ultrasound and confirmed by excretory urography, or diethylenetriaminepentaacetic acid or dimercapto-succinic acid scan. A voiding cystourethrogram was performed in 40 patients (87%).

RESULTS

Associated urological anomalies were present in 22 of the 46 patients (48%) with unilateral renal agenesis, including primary vesicoureteral reflux in 13 (28%), ureterovesical junction obstruction in 5 (11%), ureteropelvic junction obstruction in 3 (7%), and ureterovesical and ureteropelvic junction obstruction in 1 (2%). Of the 22 patients 14 (64%) underwent surgical intervention.

CONCLUSIONS

Nearly half of the patients with unilateral renal agenesis had associated urological anomalies. Vesicoureteral reflux was the most common associated anomaly and it was usually of high grade. Early recognition and treatment of urological anomalies in a patient with a solitary kidney are imperative to decrease the long-term risk of renal damage.

Renal agenesis, ureteral ectopia into seminal vesicle, vas deferens agenesis and hemivertebra: an incomplete form of caudal regression syndrome?

The association of seminal vesicle cyst and upper urinary tract malformation is well known in the literature [1]. More rarely, urogenital malformations are associated with vertebral [2] or anorectal anomalies [3]. A 35-year-old infertile man with unilateral renal and deferential agenesis, seminal vesicle cyst and hemivertebra is reported. This complex malformative syndrome has been reported previously by Sheih et al. [4] and, to our knowledge, this is the third case described in the literature.

The preparticipation sports examination for high school and college athletes

The PSE can be used as a tool to allow athletes to participate safely in sports. The goal of the PSE is not to disqualify athletes but to ensure that their participation in sports does not unnecessarily increase their risk of injury. The PSE is most effectively conducted by the station method with multiple examiners, one of whom should have specialty training in musculoskeletal disorders. The examination should be conducted 6 weeks prior to the beginning of the season and at the beginning of each new level of competition, unless directed differently by local laws. The correct use of the PSE should screen for signs and symptoms of pathological states that may lead to a nontraumatic death while participating in sports. An effective musculoskeletal examination should detect any postinjury deficits that may lead to subsequent reinjury later in the season. It is our hope that a PSE, based on the literature, can be used to prevent some of the nontraumatic deaths and musculoskeletal injury associated with sports participation.

Management considerations for treating vesicoureteral reflux in children with solitary kidneys

OBJECTIVES

To evaluate the management approach for vesicoureteral reflux (reflux) into a solitary kidney.

METHODS

Outcomes of all children with solitary kidneys and reflux managed between 1981 and 1996 were reviewed. Solitary kidneys were documented by nuclear renography and ultrasonography; reflux was graded after cystography. Management consisted of observation and antimicrobial prophylaxis or surgery by ureteroneocystostomy or subureteric injection of polytetrafluoroethylene (STING). Follow-up ranged from 3 months to 14 years and included serial cystography, sonography, and serum creatinine measurement.

RESULTS

Twenty-one patients with a median follow-up of 26 months were identified. Etiologies included contralateral renal agenesis (14 children), multicystic dysplastic kidney (5 children), or nonfunctioning ureteropelvic junction obstruction (2 children). Low-grade (I to II) reflux was identified in 6 children, and high grade (III to V) was identified in 15. Reflux resolved in 20 patients. Five children with low-grade reflux were managed without surgery and demonstrated reflux resolution after a mean of 20.5 months. Renal function deteriorated in only 1 child. Ureteroneocystostomy was performed in 13 children with grades III to V reflux, and STING was performed in 1 child with grade II reflux. Every surgical patient maintained stable renal function and was infection-free during a mean follow-up of 56 months. Management by observation in 2 children with grades IV to V reflux resulted in spontaneous resolution in one and stable grade IV in the other.

CONCLUSIONS

Reflux into the solitary functioning kidney may be managed by the same strategies used to manage unilateral reflux in children with two normally functioning kidneys: low-grade reflux by observation/ chemoprophylaxis until spontaneous resolution occurs, and higher grades by surgery to protect renal function; however, chemoprophylaxis and serial imaging may be used until well-defined indications for surgery are satisfied. Renal function should be monitored diligently.

Prognosis of patients with unilateral renal agenesis

The clinical course was reviewed in 157 patients with unilateral renal agenesis and a normal contralateral kidney for the purpose of establishing a prognosis. There were 85 males (54%) and 72 females (46%). The mean age at diagnosis of unilateral renal agenesis was 37 years. The mean years at risk was 56. Proteinuria (> 150 mg/24 h) was found in 19% of the 37 patients tested (P < 0.001), hypertension developed in 47% of the 47 patients tested (P = 0.010), and renal function (adjusted for age and sex) was decreased in 13% of the 32 patients tested (P = 0.001). An increased filtration fraction was found in 7 (54%) of 13 patients evaluated. At the completion of this study, 114 patients (73%) were alive, and the survival rate was similar to that of age-, sex-matched United States life tables. Forty-three patients (27%) died; 6 deaths (4%) were caused by renal failure. Our review indicates that patients with unilateral renal agenesis and a normal solitary kidney are at increased risk of proteinuria, hypertension, and renal insufficiency. Therefore, it is essential to have prolonged and careful follow-up and to employ strategies that maximize renal preservation.

Hyperfiltration-induced renal injury in normal man: myth or reality

Current knowledge fails to support the notion that adaptive hyperfiltration of the remnant kidney after donor nephrectomy is deleterious. Rather than being maladaptive, hyperfiltration appropriately compensates for the loss of functional renal mass. Accordingly, most kidney donors can be expected to maintain a stable level of renal function without proteinuria or hypertension. Essential to this is proper selection of donors for nephrectomy and exclusion of high risk potential donors, bearing in mind the fact that apparently healthy, asymptomatic relatives of end stage renal disease patients are prone to the same disease processes that inflict the general population and have a higher risk of underlying renal disease.

An approach to protein restriction in children with renal insufficiency

Children with mild to moderate renal insufficiency may be at an increased risk for developing glomerulosclerosis and subsequent renal failure. Low protein diets (LPD) have been shown to delay the progression of renal insufficiency in laboratory animals and may be of benefit in adult humans. The nutritional costs of a LPD in adults are reportedly minimal. We review the protein and caloric requirements of growing children and discuss the potential harmful effects and benefits of an LPD in this population. We also discuss dietary adherence and the difficulty of designing an LPD for children. We conclude that the protein content of a typical American diet can safely be reduced to, but not below, the recommended daily allowance for protein if diets are carefully planned, patients and their parents extensively counseled, and if dietary supplements are given to help meet the caloric and vitamin-mineral nutrient needs of growing children. In addition, ongoing nutritional assessment, counseling, and frequent monitoring of growth, diet and biochemical indicators of protein status are essential for maintaining the health of these children.

Surgery on solitary kidneys in childhood

From 1969 to 1984, 31 children were operated on for a diseased solitary kidney. There was a peak of incidence during the first 2 years of life, due mostly to congenitally malformed solitary kidneys. In contrast, operations in older children became necessary for diseased residual kidneys. In some children, secondary or even multiple operations had to be performed in order to maintain satisfactory organ function. Except in three preuraemic patients, renal functions were fully compensatory during a follow-up of 1-16 years. Former reservations regarding surgical intervention in solitary kidneys should be dropped in the face of these good operative results.

Complications of vaginal atresia in association with a duplicated mullerian duct

A mullerian duct duplication with a vaginal atresia can present as a painful abdominal mass in a female caused by a hematometrocolpos and a hemosalpinx. This set of signs and symptoms, if caused by an associated unilateral vaginal atresia, may be found in a female with normal menstrual periods, and (1) can be misdiagnosed with often tragic consequences caused by unnecessary salpingectomy, or even hysterectomy; (2) can be successfully treated by creating an adequate channel for drainage through the area of vaginal atresia; and (3) has a high association with unilateral renal agenesis. Because of this last point, recognition of either a mullerian duct duplication or unilateral renal agenesis should prompt an investigation for the other abnormality.

Skeletal anomalies associated with unilateral renal agenesis

Unilateral renal agenesis is sometimes associated with skeletal anomalies. The skeletal malformations are easily detectable and, if found, should suggest further urological investigations. The embryological aspect of the association is explored. Two cases are presented and the relevant literature is reviewed.

Persistent right umbilical vein--case report and review of literature

Persistence of the proximal portion of the right umbilical vein is described in a premature infant. Infracardiac total anomalous pulmonary venous connexion and unilateral renal agenesis with ipsilateral phocomelia and unicornuate uterus were associated anomalies. The mother had received carbamazepine therapy for epilepsy. Previously reported cases of persistent proximal right umbilical vein have shown a variety of other malformations but a single umbilical artery has been the most consistent.

Familial nature of congenital absence and severe dysgenesis of both kidneys

Seventy-one parents and 40 siblings of 41 index patients with bilateral renal agenesis, bilateral severe dysgenesis, or agenesis of one kidney and dysgenesis of the other were evaluated by gray-scale ultrasonography for genitourinary malformations. Nine per cent (10 of 111) had asymptomatic renal malformations, most often unilateral renal agenesis (4.5 per cent--a frequency that was significantly higher than the frequency of 0.3 per cent among 682 adults [P less than 0.004]). We recommend ultrasonographic screening for parents and siblings of infants born with agenesis or dysgenesis of both kidneys or with agenesis of one kidney and dysgenesis of the other, since renal malformations may have medical implications even for asymptomatic patients.

Congenital aplastic-hypoplastic lumbar pedicle in infants and young children

Nine cases of congenital aplastic-hypoplastic lumbar pedicle (mean age 27 months) are described. Their data are compared to those of 18 other reported cases (mean age 24.7 years)and the following conclusions are made: (1) Almost exclusively, the pedicular defect in infants and young children is due to developmental anomaly rather than destruction by malignancy or infectious processes. (2) This anomaly, we think, is more common than it is believed to be. (3) Unlike adults, infants and young children rarely develop hypertrophy and/or sclerosis of the contralateral pedicle. (4) Detection of pedicular anomaly is more than satisfying a radiographic curiosity and may lead to discovery of other coexisting anomalies. (5) Ultrasonic screening of the patients with congenital pedicular defects may detect the associated genitourinary anomalies, if present, and justify further studies in a selected group of patients.

Multiple genitourinary abnormalities in females with unilateral renal agenesis: three cases

We have the means to identify over 75% of infants and children with unilateral renal agenesis. It has been established that all patients with unilateral renal agenesis must be followed closely because of problems with the remaining kidney and other anomalies. It is apparent from embryologic studies and numerous reports that up to 89% of females with unilateral renal agenesis are likely to have significant accompanying genitourinary abnormalities. Most of these patients' genital problems occur at the time of puberty or pregnancy. Because of our experience with three teenage females who had unilateral renal agenesis and subsequent serious problems, we wish to advocate a prepubertal aggressive investigation.

Unilateral renal agenesis presenting as anuria

The most common cause of sudden and total cessation of urine output is obstructive uropathy, usually at the bladder outlet. Bilateral ureteral obstruction is a much less common cause of anuria. In additioh, unilateral obstruction in the presence of a solitary kidney must be considered in the differential diagnosis. Primary renal parenchymal disorders and pre-renal azotemia occasionally may be anuric but more commonly are oliguric. A case of unilateral renal agenesis presenting as anuria and obstruction of the solitary kidney is described.

Significance of absent vas deferens at hernia repair in infants and children

An absent vas deferens may be associated with unilateral renal agenesis or undiagnosed cystic fibrosis. Such patients should be further evaluated with a sweat chloride and intravenous pyelogram. The finding of absent vas deferens during exploration for an undescended testis does not provide absolute evidence for absence of the testis, since these structures have independent embryologic origins.