External validation and reliability assessment of posterior urethral morphology on initial voiding cystourethrogram as a predictor for infants with posterior urethral valves.

INTRODUCTION: The morphology of the bladder and posterior urethra on initial voiding cystourethrogram (VCUG) in posterior urethral valve (PUV) has been proposed as a meaningful early metric for short- and long-term kidney outcomes. Here, we seek to externally validate the proposed association and assess the reliability of PUV morphology characteristics. MATERIALS AND METHODS: We reviewed our institutional database for patients managed for PUV between 2000 and 2022 and included those treated with primary ablation with at least 1 year of follow-up for kidney function. Each VCUG was evaluated by three independent raters for the height-width ratio of the bladder (HW-B), height-width ratio of the posterior urethra (HW-PU), and posterior-anterior urethral ratio (PA-UR), and trabeculation (none, fine, or coarse). We assessed the reliability in these with intra-class coefficient and Fleiss kappa for continuous and categorical data, respectively. We performed univariate analysis with nadir creatinine and five-year follow-up glomerular filtration rate (GFR). RESULTS: In total, 98 patients met inclusion criteria. The median age at diagnosis and ablation was 10 and 21 days, respectively. Patients with nadir creatinine <0.8 mg/dL had higher follow-up GFR (101 vs. 20 ml/min/1.73 m2, p = 0.04), and lower risk of CKD (odds ratio 14.7, p = 0.002). The median value for HW-B was 1.4, median HW-PU was 2.1, and median PA-U was 4.7, There was significant inter-class agreement between all three measures of 0.80, 0.51, and 0.70 (p < 0.001). The inter-rater agreement for bladder trabeculation was fair (Fleiss K = 0.40, p < 0.001). There was no statistically significant correlation between HW-B, HW-PU, PU-A with nadir creatinine (p = 0.07, 0.33, 0.91) or 5-year GFR (0.27, 0.45, 0.62), respectively. DISCUSSION: There is significant interest in determining prognostic factors and metrics in PUV. The morphological characteristics on VCUG are reliable and is available information for all boys diagnosed with PUV, resulting in an attractive metric. While we do not demonstrate correlation with kidney outcomes, VCUG features warrant further attention as prognostic factors in PUV. CONCLUSIONS: PUV morphology on initial VCUG is a reliable metric of lower urinary tract deformity but is not associated with 5-year kidney outcomes.

Congenital lower urinary tract obstruction with spontaneous fetal bladder rupture due to posterior urethral valves: a case report.

BACKGROUND: Congenital lower urinary tract obstruction (LUTO) is a rare but significant condition affecting fetal urinary tract development. LUTO has a range of etiologies, with posterior urethral valves (PUV) being the most common cause. The prenatal diagnosis of LUTO plays a crucial role in recognizing the condition and guiding management decisions. Prenatal ultrasound serves as the primary tool for identifying LUTO, with key findings including megacystis, bladder wall thickening, oligohydramnios, hydronephrosis, and the 'keyhole sign' indicating dilatation of the posterior urethra. We present a case of congenital LUTO with a rare complication of spontaneous fetal bladder rupture and urinary ascites, treated by peritoneo-amniotic shunt placement. CASE PRESENTATION: A 27-year-old pregnant Caucasian women was referred at 28 weeks of pregnancy due to the presence of megacystis and bilateral hydronephrosis on routine ultrasound and suspicion of LUTO. Repeat ultrasound at 29 weeks showed significant fetal ascites, oligohydramnios and resolution of megacystis and hydronephrosis, after which diagnosis of spontaneous bladder rupture was made. Despite ascites aspiration and amnio-infusion, there was persistent ascites and oligohydramnios. A peritoneo-amniotic shunt was placed with resolution of ascites and normalization of the amniotic fluid volume. At 35 weeks, relapse of the megacystis was observed with bilateral pyelectasis and oligohydramnios, possibly due to healing of the bladder rupture, after which elective cesarean section was planned. Cystography confirmed spontaneous healing of the bladder rupture and the presence of posterior urethral valves, which were resected in the neonatal period with cold knife incision. Total follow-up of 8 years continued to show positive ultrasonographic results and good renal function, but the child suffers from bladder dysfunction, manifesting as overactive bladder disease. CONCLUSIONS: LUTO might lead to important renal dysfunction and pulmonary hypoplasia in case of increasing disease severity. Spontaneous bladder rupture might improve renal prognosis, acting as a pop-off mechanism by decompression of the urinary tract. However, fetal bladder rupture is rare and only few cases have been reported. Prenatal intervention can be considered for moderate or severe LUTO, but the benefit for long-term outcome remains uncertain and further studies are needed.

Urethral obstruction from Cobb's collar in association with VACTERL.

SUMMARY: Cobb's collar is a rare intraluminal congenital cause of bulbar urethral obstruction that is commonly mislabelled congenital obstructive posterior urethral membrane (COPUM) but may be distinguished from this endoscopically as it has no connecting folds to the verumontanum. In this report, Cobb's collar is described for the first time in association with the VACTERL syndrome. The abnormality was diagnosed and treated by diathermy and dilatation at the time of endoscopic evaluation, with improvement of vesicoureteric reflux on micturating cystourethrogram and renal ultrasound.

Case report laparoscopy-assisted pre-pubic urethrostomy as a palliative procedure for resection of distal urethral tumor in a female dog.

BACKGROUND: This paper presents the first described case of laparoscopy-assisted prepubic urethrostomy and laparoscopic resection of a tumor of the distal part of the urethra in a female dog as a palliative treatment. CASE PRESENTATION: An intact, 11 -year-old, mixed breed female dog, weighing 15 kg, was admitted with signs of urinary obstruction and difficulty with catheterization. Vaginal, rectal, and endoscopic examinations revealed a firm mass in the pelvic cavity at the level of the pelvic urethra. Ultrasound and computed tomography examination showed enlargement of the urethral wall (5.5 cm width and 3 cm thick), which was significantly restricting the patency of the urethra. The lesion affected only the distal part of the urethra without the presence of local or distant metastatic changes. The affected portion of the urethra was laparoscopically removed while performing pre-pubic urethrostomy with laparoscopy. The patient regained full consciousness immediately after the end of anesthesia, without signs of urinary incontinence. Histopathological examination of the removed urethra revealed an oncological margin only from the side of the bladder. In the period of 2.5 months after the procedure, the owner did not notice any symptoms that could indicate a postoperative recurrence, which was diagnosed three months after the procedure. CONCLUSIONS: Pre-pubic urethrostomy can be successfully performed with the assistance of laparoscopy. The use of minimally invasive surgery will allow, in selected cases, removal of the urethral tumor, and in inoperable cases, to perform a minimally invasive palliative pre-pubic urethrostomy.

Z-scores of fetal bladder size for antenatal differential diagnosis between posterior urethral valves and urethral atresia.

OBJECTIVE: To construct reference values for fetal urinary bladder distension in pregnancy and use Z-scores as a diagnostic tool to differentiate posterior urethral valves (PUV) from urethral atresia (UA). METHODS: This was a prospective cross-sectional study in healthy singleton pregnancies aimed at constructing nomograms of fetal urinary bladder diameter and volume between 15 and 35 weeks' gestation. Z-scores of longitudinal bladder diameter (LBD) were calculated and validated in a cohort of fetuses with megacystis with ascertained postnatal or postmortem diagnosis, collected from a retrospective, multicenter study. Correlations between anatomopathological findings, based on medical examination of the infant or postmortem examination, and fetal megacystis were established. The accuracy of the Z-scores was evaluated by receiver-operating-characteristics (ROC)-curve analysis. RESULTS: Nomograms of fetal urinary bladder diameter and volume were produced from three-dimensional ultrasound volumes in 225 pregnant women between 15 and 35 weeks of gestation. A total of 1238 urinary bladder measurements were obtained. Z-scores, derived from the fetal nomograms, were calculated in 106 cases with suspected lower urinary tract obstruction (LUTO), including 76 (72%) cases with PUV, 22 (21%) cases with UA, four (4%) cases with urethral stenosis and four (4%) cases with megacystis-microcolon-intestinal hypoperistalsis syndrome. Fetuses with PUV showed a significantly lower LBD Z-score compared to those with UA (3.95 vs 8.83, P < 0.01). On ROC-curve analysis, we identified 5.2 as the optimal Z-score cut-off to differentiate fetuses with PUV from the rest of the study population (area under the curve, 0.84 (95% CI, 0.748-0.936); P < 0.01; sensitivity, 74%; specificity, 86%). CONCLUSIONS: Z-scores of LBD can distinguish reliably fetuses with LUTO caused by PUV from those with other subtypes of LUTO, with an optimal cut-off of 5.2. This information should be useful for prenatal counseling and management of LUTO. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Check cystoscopy in the management of anterior urethral valves in a cohort of pediatric patients.

INTRODUCTION: Anterior urethral valves (AUV) are a rare cause of lower urinary tract obstruction which could progress to renal damage, Clinical presentation varies according with patient's age and severity of obstruction, but, in most cases, diagnosis is based on voiding cysto-urethrogram (VCUG). To date, the treatment of choice is endoscopic ablation even if approved guidelines about the overall management of AUVs, including the recognition and treatment of residual valves, are not available. OBJECTIVE: We describe our protocol for AUV treatment based on primary endoscopic valve ablation followed by check cystoscopy 15 days later. STUDY DESIGN: Medical records of 5 patients with AUVs admitted from 2008 to 2018 to our Pediatric Urology Unit were retrospectively reviewed. Blood tests, urinalysis, renal US and VCUG were performed in all children, while urodynamic evaluation was performed in the 3/5 patients who could void spontaneously. All patients underwent endoscopic valves ablation and after 15 days after a second look cystoscopy was performed. Follow up was based on clinical and radiological evaluation with US, urinalysis and blood tests. Postoperative non-invasive urodynamic studies were performed in the 3/5 patient toilet-trained patients and VCUG was performed in 1/5 patient. RESULTS: and Discussion: At primary endoscopic ablation cystoscopy revealed AUVs in the penile urethra in three patients, in the penoscrotal urethra in one case, in the bulbar urethra in another case. In 3/5 patients check cystoscopy found residual valves and a second endoscopic ablation was performed. All patients achieved symptoms release and improved urodynamic parameters. No intra or post-operative complication were reported. The assessment of residual valves is variable in literature and it is usually described for posterior urethral valves (PUVs). Few series report the use of VCUG within the first week after valve ablation, our experience instead suggests that performing a second look cystoscopy, is very effective to evaluate the presence of residual AUVs and eventually proceed with further ablation. CONCLUSION: Endoscopic ablation is the gold standard treatment for AUV, but residual valves management is not clearly defined. According to our experience, a check cystoscopy 15 days after primary ablation allows to identify and treat possible residual valves showing good results in terms of safety and efficacy.

Primary infertility secondary to a hidden posterior urethral valve representing a diagnostic challenge in the fifth decade.

Posterior urethral valves (PUVs) are frequently recognized during the perinatal period. Delayed diagnosis is reported usually within the first decade of life with diverse clinical presentations. In the current case report, we describe a 45 years old man patient who presented with aspermia and primary infertility for 8 years in whom his diagnostic workup revealed radiological imaging suggestive of PUVs. This phenomenon was confirmed by cystourethroscopy that showed obstructive valve. Endoscopic ablation resulted in significant improvement of his seminal parameter with successful conception.

Neurodevelopmental Outcome in Infants with Lower Urinary Tract Obstruction Based on Different Degrees of Severity.

OBJECTIVE: To determine postnatal neurodevelopmental (ND) outcomes for children with congenital lower urinary tract obstruction (LUTO) based on disease severity. METHODS: Twenty male infants with LUTO were classified prenatally as Stage 1 (normal amniotic fluid and renal function; n = 5), Stage 2 (signs of obstruction with preserved renal function; n = 13), and Stage 3 (signs of severe renal damage; n = 2). ND status was assessed using the Developmental Profile-3 test in 5 developmental domains (physical, adaptive behavior, social-emotional, cognitive, and communication). Each domain was considered to be delayed if standard scores were 2 or more SD below the mean. ND outcomes were compared between cases with an expected normal renal function (LUTO Stage 1) and those with impaired renal function (LUTO Stages 2 and 3). Results from cases with Stage 2 were also compared to those from Stage 3. ORs were calculated to predict risk for adverse ND outcome for each domain considering prenatal and postnatal factors. RESULTS: Gestational age (GA) at the diagnosis of LUTO was similar between both groups (Stage 1: 24.85 ± 7.87 vs. Stages 2 and 3: 21.4 ± 4.31 weeks; p = 0.24). Twelve of 15 cases with Stage 2 or 3 underwent vesicoamniotic shunt placement compared to none of Stage 1 fetuses (p < 0.01). No differences in GA at delivery were detected between the groups (37.9 ± 1.6 vs. 35.1 ± 3.6 weeks; p = 0.1). One of the infants in the Stage 2 and 3 groups received a kidney transplant during follow-up. One case (20%) from Stage 1 group required dialysis during the first 6 months of life, and 1 case from Stage 2 to 3 group required it during the first 6 months (p = 1.0), whereas 3 additional cases needed dialysis from 6 to 24 months (p = 0.6). Mean age at Developmental Profile 3 (DP-3) testing was 20.3 ± 12.3 months (Stage 1: 11.2 ± 8.6 vs. Stages 2 and 3: 23.4 ± 13.4 months; p = 0.07). Fifteen of the 20 patients (75%) had no ND delays. Of the 5 patients with ND delays, 4 received dialysis. No differences in ND outcomes between infants with LUTO Stage 1 and those with Stages 2 and 3 were detected except for a trend toward better physical development in Stage 1 (102.6 ± 11.6 vs. 80.7 ± 34.9; p = 0.05). Infants diagnosed with LUTO Stage 3 showed significantly lower adaptive scores than those diagnosed with Stage 2 (Stage 2: 101.9 ± 22.3 vs. Stage 3: 41.5 ± 30.4; p = 0.04) and a nonsignificant trend for lower results in physical (85.8 ± 33.0 vs. 47.5 ± 38.9; p = 0.1) and socio-emotional (94.7 ±17.9 vs. 73.5 ± 13.4; p = 0.1) domains. Infants who received dialysis showed 15-fold increased risk (95% CI 0.89-251) for delayed socio-emotional development (p = 0.06). Diagnosis of fetal renal failure increased the risk for delays in the adaptive domain 30-fold (95% CI 1.29-93.1; p = 0.03). Infants with abnormal renal function had 19 times (95% CI 1.95-292) increased risk for delays in the physical domain (p = 0.03). CONCLUSIONS: While most patients with LUTO do not exhibiting ND delays, our results support the importance of ND monitoring, especially in severe forms of LUTO, as increased severity of this condition may be associated with poorer ND outcomes.

Fetal lower urinary tract obstruction: What should we tell the prospective parents?

Fetal lower urinary tract obstruction (LUTO), which often results in marked perinatal morbidity and mortality, is caused by a heterogeneous group of anatomical defects that lead to blockage of the urethra. The classic prenatal presentation of LUTO includes megacystis with hydronephrosis. While mild forms of the disease can be associated with favorable outcomes, more severe disease commonly leads to dysplastic changes in the fetal kidneys, and ultimately oligohydramnios, which can result in secondary pulmonary hypoplasia and renal failure at birth. The aim of this review is to provide practitioners with a general overview of the diagnosis and treatment of LUTO based on disease severity, along with some points to consider when counseling prospective parents of fetuses with this condition.

Etiology and management of early pregnancy renal anhydramnios: Is there a place for serial amnioinfusions?

Early pregnancy renal anhydramios (EPRA) comprises congenital renal disease that results in fetal anhydramnios by 22 weeks of gestation. It occurs in over 1 in 2000 pregnancies and affects 1500 families in the US annually. EPRA was historically considered universally fatal due to associated pulmonary hypoplasia and neonatal respiratory failure. There are several etiologies of fetal renal failure that result in EPRA including bilateral renal agenesis, cystic kidney disease, and lower urinary tract obstruction. Appropriate sonographic evaluation is required to arrive at the appropriate urogenital diagnosis and to identify additional anomalies that allude to a specific genetic diagnosis. Genetic evaluation variably includes karyotype, microarray, targeted gene testing, panels, or whole exome sequencing depending on presentation. Patients receiving a fetal diagnosis of EPRA should be offered management options of pregnancy termination or perinatal palliative care, with the option of serial amnioinfusion therapy offered on a research basis. Preliminary data from case reports demonstrate an association between serial amnioinfusion therapy and short-term postnatal survival of EPRA, with excellent respiratory function in the neonatal period. A multicenter trial, the renal anhydramnios fetal therapy (RAFT) trial, is underway. We sought to review the initial diagnosis ultrasound findings, genetic etiologies, and current management options for EPRA.

Antenatal intervention for congenital fetal lower urinary tract obstruction (LUTO): a systematic review and meta-analysis.

Objective: To evaluate the effectiveness of antenatal intervention for the treatment of congenital lower urinary tract obstruction (LUTO) in improving perinatal survival and postnatal renal function.Methods: Electronic databases were searched from their inception until May 2018. Selection criteria included randomized controlled trials and nonrandomized studies including fetuses with ultrasound evidence of LUTO evaluating antenatal intervention for improving perinatal outcomes. Any type of antenatal bladder drainage technique was analyzed. The primary outcome was perinatal survival. The secondary outcome was postnatal survival with normal renal function. The summary measures were reported as summary odds ratio (OR) with 95% of confidence interval (CI).Results: Ten articles with a total of 355 fetuses were included in the meta-analysis. Inclusion criteria of the selected studies were singleton pregnancy with severe LUTO confirmed on detailed fetal ultrasound examination. Nine studies analyzed the efficacy of vesico-amniotic shunt performed in the second trimester. The overall estimate survival was higher in the vesico-amniotic shunt group compared to the conservative group (OR: 2.54, 95% CI: 1.14-5.67). 64/112 fetuses (57.1%) survived in the vesico-amniotic shunt group compared to 52/134 (38.8%) in the control group. Five studies reported on postnatal renal function between 6 months and 2 years. Rate of good postnatal renal function was higher in the vesico-amniotic shunt group compared to the conservative group (OR: 2.09, 95% CI: 0.74-5.9). Fetal cystoscopy was performed in only two included studies. Overall, 45 fetuses underwent fetal cystoscopy. The perinatal survival was higher in the cystoscopy group compared to the conservative management group (OR: 2.63, 95% CI: 1.07-6.47). Normal renal function was noted in 13/34 fetuses in the cystoscopy group versus 12/61 in the conservative management group at 6 months follow-up (OR: 1.75, 95% CI: 1.05-2.92)Conclusions: Antenatal bladder drainage appears to improve perinatal survival in cases of LUTO.

Association of abdominal effusion with a single decompressive cystocentesis prior to catheterization in male cats with urethral obstruction.

OBJECTIVE: To evaluate the occurrence of abdominal effusion and its association with decompressive cystocentesis in male cats with urethral obstruction. DESIGN: Prospective observational clinical study. ANIMALS: Forty-five male neutered, client-owned cats with naturally occurring urethral obstruction. PROCEDURES: Laboratory testing and point-of-care ultrasonography were performed. Presence of abdominal effusion was evaluated using the Focused Assessment with Sonography for Trauma (FAST) technique at presentation. Decompressive cystocentesis was then performed prior to catheterization by a standardized technique. Repeat FAST examination was performed 15 minutes after cystocentesis and the following day to further assess for the presence of abdominal effusion. RESULTS: A mean volume of 92.3 ± 35.2 mL of urine was removed from each cat via cystocentesis prior to catheterization. At presentation, 15 of 45 (33%) had abdominal effusion (13/15 with scant effusion, 2/15 with mild), with an additional 7 cats developing scant effusion 15 minutes post-cystocentesis. By the following day, 4 cats still had scant effusion present. No significant complications secondary to cystocentesis were reported. No association was found between severity of azotemia, or volume removed by cystocentesis, and the presence of effusion at presentation or after decompressive cystocentesis was performed. CONCLUSIONS AND CLINICAL RELEVANCE: A single decompressive cystocentesis prior to catheterization did not lead to development of clinically significant abdominal effusion or other discernable complications and appears to be a safe procedure in this population of patients. Abdominal effusion may be found at presentation in cats with urethral obstruction. The significance of this effusion remains to be determined.

Posterior urethral valve and anterior rectal duplication: a new combination.

We present a rare case of association of anterior rectal duplication and posterior urethral valve (PUV). A term neonate with no antenatal concerns was admitted with urosepsis and acute renal injury at 18 days of age. History revealed a poor urinary stream and dribbling. After resuscitation and stabilisation, renal tract ultrasound and micturating cysto-urethrogram were performed. Cystourethroscopy showed PUV and a mass indenting the bladder posteriorly. MRI confirmed the presence of a cystic lesion anterior to the rectum suspicious of rectal duplication. Laparoscopic-assisted excision of the anterior rectal duplication cyst was then performed. The infant recovered uneventfully. Creatinine normalised postoperatively and has been stable at follow-up.

Urine biochemistry to predict long-term outcomes in fetuses with posterior urethral valves.

OBJECTIVE: Because the literature on the predictive value of fetal urinalysis is controversial in fetuses with lower urinary tract obstruction, we determined the best model of fetal urine biochemical markers correlated with long-term postnatal renal function based on glomerular filtration rate (GFR). METHOD: This retrospective study concerned 89 fetuses with lower urinary tract obstruction and their renal function after 10 years of age. We correlated fetal urine biochemical markers (total protein, ß2-microglobulin, sodium, chloride, glucose, calcium, and phosphorus) with GFR at 10 to 30 years of age in 89 patients with posterior urethral valves. We defined five stages of chronic kidney disease (CKD). RESULTS: Of the 89 patients, 18 (20%) are 20 years old or over. Postnatal renal function was good in 67.4% (GFR > 60 mL/min/1.73 m2 ) and poor in 17% (GFR < 30 mL/min/1.73 m2 ). All fetal urine markers differed between CKD stage 1 + 2 and CKD stage 4 + 5 (P < 0.001). ß2-microblobulin showed an 87% sensitivity for a 72% specificity. A combination of ß2-microglobulin and chloride gave the best results (93% sensitivity and 71% specificity) versus amniotic fluid volume (80% sensitivity and 73% specificity). CONCLUSION: Fetal urine biochemistry predicts long-term (10-30 years) postnatal renal function.

Current State of Fetal Intervention for Lower Urinary Tract Obstruction.

PURPOSE OF THE REVIEW: In this article, we explore the origins of intervention of fetal lower urinary tract obstruction, and we specifically discuss the background and recent outcomes of vesicoamniotic shunt placement and fetal cystoscopy. The article seeks to provide a comprehensive overview of the field while bringing the reader quickly up to speed on the pertinent literature and the critical data that are available to guide decision-making regarding intervention. RECENT FINDINGS: Appropriate patient selection for fetal intervention remains challenging despite advances in prenatal imaging. Both a randomized controlled trial and multiple systematic reviews show evidence of a perinatal survival benefit following fetal intervention but rates of renal morbidity remain very high. Despite 30 years of research, fetal lower urinary tract obstruction remains a difficulty entity to treat. Intervention may lead to survival, but physicians and caregivers must remain alert for the distinct possibility of long-term renal morbidity in survivors.

Fetal surgery for lower urinary tract obstruction: the importance of staging prior to intervention.

Fetal lower urinary tract obstruction (LUTO) is a heterogeneous pathology associated with a high morbidity and mortality due to pulmonary hypoplasia. Previously, when a fetus was diagnosed on ultrasound with LUTO, expectant care or termination was the only option; this has changed because of fetal surgical intervention. Vesicoamniotic shunts and cystoscopy are the current methods utilized to treat LUTO; however, it remains difficult to determine whether fetal prognosis favors intervention and long-term outcome follow-up has been limited. This review covers the history and current challenges of fetal intervention for obstructive uropathies. We also present the Ruano's LUTO staging system which integrates information from fetal urine analysis with ultrasound findings to assess whether a specific fetal intervention is recommended. Utilizing a standard staging system that is readily adopted by providers carrying out fetal surgery is crucial for determining the true impact on outcomes intervention has on fetuses diagnosed with LUTO.

Natural History of Fetal Lower Urinary Tract Obstruction with Normal Amniotic Fluid Volume at Initial Diagnosis.

OBJECTIVE: The aim of this study was to define the natural history of lower urinary tract obstruction (LUTO) with normal midgestational amniotic fluid volumes. MATERIALS AND METHODS: We performed a retrospective review of 32 consecutive patients with LUTO with normal midgestational amniotic fluid volume followed at 11 North American Fetal Therapy Network (NAFTNet) centers from August 2007 to May 2012. Normal amniotic fluid volume was defined as an amniotic fluid index (AFI) of ≥9 cm. RESULTS: The mean gestational age (GA) and AFI at enrollment were 23.1 ± 2.1 weeks and 15.8 ± 3.9 cm, respectively. The mean GA at delivery was 37.3 ± 2.8 weeks. The mean creatinine level at discharge was 1.2 ± 0.8 mg/dL. Perinatal survival was 97%. Twenty-five patients returned for serial postnatal assessment. Renal replacement therapy (RRT) was required in 32%. Development of oligohydramnios and/or anhydramnios, development of cortical renal cysts, posterior urethral valves, prematurity, and prolonged neonatal intensive care unit stay were associated with need for RRT (p < 0.05) by univariate analysis. By multivariate analysis, preterm delivery remained predictive of need for RRT (p = 0.004). CONCLUSION: Prenatal diagnosis of LUTO with normal midgestational amniotic fluid volumes is associated with acceptable renal function in the majority of patients. Approximately one-third of these children require RRT. Surrogate markers of disease severity appear to be predictive of need for RRT.

Obstrução do Trato Urinário Baixo Fetal / Fetal lower urinary tract obstruction

A obstrução do trato urinário baixo fetal (fetal lower urinary tract obstruction - LUTO) é uma patologia caracterizada por dilatação da bexiga e hidronefrose bilateral causada por obstrução do trato urinário inferior. Sua incidência é de 2,2 em cada 10.000 nascimentos. A etiologia da LUTO inclui a válvula da uretra posterior (VUP), atresia ou estenose uretral. O diagnóstico é feito por ultrassom, que mostra bexiga dilatada, com paredes espessas (megabexiga), e uretra posterior aumentada. O tratamento cirúrgico clássico (derivação vésico-amniótica guiada por ultrassom) estaria indicado quando o líquido amniótico normal começa a diminuir, com aumento da distensão vesical e da hidronefrose. O tratamento inclui a colocação de derivação vésico-amniótica guiado pelo ultrassom e fetoscópica com coagulação a laser. De acordo com a gravidade, a LUTO é classificada nos estágios 1,2 e 3.(AU)

The Fetal Lower Urinary Tract Obstruction (LUTO) is a spectrum of diseases characterized by bladder distension and bilateral hydronephrosis in consequence of the LUTO. The incidence is approximately 2.2 in 10,000 births and it is commonly diagnosed during the late first or early second trimester of pregnancy. The etiologies of LUTO include posterior urethral valves, urethral atresia and urethral stenosis. Complete bladder outlet obstruction (severe LUTO) is associated with high perinatal mortality due to pulmonary hypoplasia and severe renal impairment/damage. The prenatal intervention includes vesicoamniotic shunt placement guided by ultrasound and fetoscopic laser coagulation. It is suggested that LUTO patients could be categorized in three stages according to disease gravity: Stages 1, 2 and 3.(AU)