Moderate and severe fetal pyelectasis: Correlation between prenatal aspects and postnatal outcome.

BACKGROUND: Renal pelvic dilatation (RPD) is a frequent finding in fetal ultrasound. The aim of the study is to correlate the prenatally detected moderate and severe pyelectasis with the postnatal outcome. METHODS: A retrospective analysis involving 90 cases of prenatally detected moderate and severe RPD referred to our prenatal diagnosis centre with 18 months of urological follow-up. Prenatal ultrasound was correlated with postnatal renal function, assessed by plasmatic creatinine and/or renal scintigraphy performed before surgery. RESULTS: Cases were divided between two groups according to postnatal management: group A including 35 newborns (38.9%) that needed surgical treatment and group B with 55 patients (61.1%) who were managed conservatively. The group A presented higher median RPD (18 mm, IQR 12-25 mm) compared to the group B (11 mm, IQR 10-14 mm). The most common anomaly detected within group A was pelvi-ureteric junction (PUI) obstruction (43%). Within group B 32 cases (58%) showed spontaneous resolution of hydronephrosis during postnatal follow up. In case of moderate pyelectasis the risk of postnatal surgery was 25% and raised to 60% for severe RPD. In our study, 29 newborns showed pathologic scintigraphies: 25 required surgery while 4 did not find indication for surgery due to ipsilateral renal function irreversible damage. 6 patients had high creatinine level (>0.6 mg/dl). 35 cases out of 90 (39%) developed monolateral irreversible renal function impairment. CONCLUSION: Moderate and severe RPD are often correlated with postnatal renal damage, therefore a close multidisciplinary follow-up is required. Prenatal scanning is highly predictive of postnatal outcome and can address properly the prenatal counseling.

Prenatal natural history of isolated fetal mild bilateral pyelectasis

OBJECTIVE: To analyze the prenatal outcomes in a cohort of fetuses with mild bilateral pyelectasis and determine whether performing serial ultrasounds is a good follow-up strategy. METHODS: A prospective longitudinal study was conducted on 62 fetuses with mild bilateral pyelectasis. Fetal mild bilateral pyelectasis was considered when the renal pelvis measured (in millimeters) ≥5.0 to 10.0, ≥7.0 to 10.0, and ≥10.0 to 15 at ≤23 weeks 6 days, 24 to 31 weeks 6 days, and ≥32 weeks, respectively, with no uretero-calyceal dilatation. Ultrasounds were performed every 3 weeks to assess whether the mild bilateral pyelectasis regressed, remained unchanged (Group 1) or progressed (Group 2). RESULTS: Group 1 consisted of 53 fetuses (85.4%), and progression was observed in 9 cases (Group 2, 14.6%). The initial renal pelvis diameter was significantly larger in fetuses with progression (p=0.028). Statistically significant differences in the renal pelvis diameter were also found at weeks 31 and 35 for both kidneys (p<0.05). The cases requiring intrauterine procedures or early delivery were not observed. CONCLUSION: Fetal mild bilateral pyelectasis with no calyceal dilatation is a benign condition that can be managed in the postnatal period. The initial renal pelvis diameter and the diameter in week 31 or 35 were valuable parameters for identifying cases that would eventually need specific postnatal procedures.

Ultrasound screening: Status of markers and efficacy of screening for structural abnormalities.

Aneuploidy is a major cause of perinatal morbidity and mortality and can have a significant impact on expecting parents and their families. With early screening and diagnosis it is important to be able to educate parents regarding the potential impact of the diagnosis. This knowledge allows parents the opportunity to consider management options early in the pregnancy, permitting more time to mentally and emotionally prepare both for the course of the pregnancy, and after the birth of the child should the pregnancy continue. Prenatal screening provides pregnant women a non-invasive risk assessment for the most common aneuploidies. Those who are considered "high-risk" then have the option for additional diagnostic (invasive) testing. Prior to the 1980s, prenatal screening consisted of risk assessment through maternal age; however, with the advent of maternal serum biochemical analysis and ultrasound, the field of prenatal screening developed significantly. As biochemical and sonographic advances continued into the 1990s, the emphasis shifted to risk assessment in the first trimester, with the combination of maternal serum analytes and sonographic evaluation of the nuchal translucency.(1) Within the last decade, the introduction of non-invasive screening (NIPT/S) has shown great impact on the expansion and evolving practice of prenatal screening. Although in many places the standard for prenatal testing continues to include maternal serum analytes and sonographic evaluation, the role of each marker alone and in combination remains important. In the era of increasingly available screening tests, especially with NIPT/(NIPS), this article attempts to review the current role of ultrasound in prenatal care and elucidate the role of ultrasound markers in prenatal screening.

Controversial ultrasound findings in mid trimester pregnancy. Evidence based approach.

Mid trimester fetal anatomy scan is a fundamental part of routine antenatal care. Some U/S soft markers or controversial U/S signs are seen during the scan and create some confusion regarding their relation to fetal chromosomal abnormalities. Example of these signs: echogenic focus in the heart, echogenic bowel, renal pyelectasis, ventriculomegaly, polydactely, club foot, choroid plexus cyst, single umbilical artery. We are presenting an evidence based approach from the literature for management of these controversial U/S signs.

Influence of second-trimester ultrasound markers for Down syndrome in pregnant women of advanced maternal age.

The objective of the present study was to evaluate the influence of second-trimester ultrasound markers on the incidence of Down syndrome among pregnant women of advanced maternal age. This was a retrospective cohort study on 889 singleton pregnancies between the 14th and 30th weeks, with maternal age ≥ 35 years, which would undergo genetic amniocentesis. The second-trimester ultrasound assessed the following markers: increased nuchal fold thickness, cardiac hyperechogenic focus, mild ventriculomegaly, choroid plexus cysts, uni- or bilateral renal pyelectasis, intestinal hyperechogenicity, single umbilical artery, short femur and humerus length, hand/foot alterations, structural fetal malformation, and congenital heart disease. To investigate differences between the groups with and without markers, nonparametric tests consisting of the chi-square test or Fisher's exact test were used. Moreover, odds ratios with their respective 95% confidence intervals were calculated. Out of the 889 pregnant women, 131 (17.3%) presented markers and 758 (82.7%) did not present markers on the second-trimester ultrasound. Increased nuchal fold (P < 0.001) and structural malformation (P < 0.001) were the markers most associated with Down syndrome. The presence of one marker increased the relative risk 10.5-fold, while the presence of two or more markers increased the risk 13.5-fold. The presence of markers on the second-trimester ultrasound, especially thickened nuchal fold and structural malformation, increased the risk of Down syndrome among pregnant women with advanced maternal age.

Second trimester ultrasound markers of fetal aneuploidy.

Although it is widely accepted that the best time to screen for chromosomal abnormalities is the first trimester, ultrasound evaluation of the fetus in the second trimester has also been shown to be useful for this purpose. A multitude of markers of varying strength has been developed over the past 30 years. In addition, the optimal time to diagnose fetal anomalies with confidence is also the mid second trimester. Therefore, performance of obstetrical ultrasound at this point in gestation continues to be an important component of prenatal care.

Prenatal anteroposterior pelvic diameter cutoffs for postnatal referral for isolated pyelectasis and hydronephrosis: more is not always better.

PURPOSE: Congenital hydronephrosis and isolated pyelectasis are frequently diagnosed by prenatal ultrasound. About 80% of cases resolve spontaneously in early childhood. Currently there is no agreed on protocol for prenatal followup. Most clinicians use a renal pelvis anteroposterior diameter of greater than 4 mm as a threshold for identifying isolated pyelectasis and hydronephrosis at 33 weeks of gestation or anteroposterior diameter greater than 7 mm at 40 weeks of gestation. We sought to determine a fetal renal pelvis diameter cutoff at 20 and 30 weeks of gestation that would be able to predict significant nephron uropathy requiring surgery. MATERIALS AND METHODS: Our protocol included 2 prenatal ultrasounds at 20 and 30 weeks of gestation and 3 postnatal ultrasounds at ages 1, 6 and 12 months. Between January 2009 and December 2011 we evaluated 149 prenatal cases (130 males, 19 females) of isolated pyelectasis and 41 cases (28 males, 13 females) of hydronephrosis with a renal pelvis anteroposterior diameter of greater than 4 mm at 20 weeks of gestation. RESULTS: For isolated pyelectasis we identified cutoffs of 6 mm at 20 weeks of gestation (100% sensitivity, 84.3% specificity) and 10 mm at 30 weeks of gestation (100% sensitivity, 91.9% specificity). For hydronephrosis we identified cutoffs of 10 mm at 20 weeks of gestation (100% sensitivity, 86.1% specificity) and 12 mm at 30 weeks of gestation (100% sensitivity, 66.7% specificity). CONCLUSIONS: Using these thresholds, we could avoid a significant number of followup ultrasounds in the prenatal and postnatal periods, as well as invasive postnatal tests (ie voiding cystourethrography and mercaptoacetyltriglycine scintigraphy) without missing even a single case of obstructive nephropathy requiring surgery.

Fetal hydronephrosis: does adding an extra parameter improve detection of neonatal uropathies?

OBJECTIVE: The aim of this study is to assess the correlation of the average antero-posterior, transverse and longitudinal diameters of the fetal renal pelvis to neonatal outcome. METHODS: This retrospective study evaluates the neonatal outcome of all fetuses with suspected pyelectasis on ultrasonographic examination between May 1997 and March 2006. During this time, 764 fetuses with pyelectasis and 1285 renal units were scanned. We defined fetal pyelectasis as mild if the ARP was ≥ 5-<10 mm, moderate if ARP ≥ 10-<15 mm and severe if ARP ≥ 15 mm. A total of 612 fetuses met the inclusion criteria. The Corteville criteria in the third trimester (antero-posterior diameter ≥ 7 mm) and an antero-posterior diameter (AP) of ≥ 10 mm were compared with the ARP and likelihood ratio's calculated. Ultrasonographic evaluation took place in the third trimester if fetal pyelectasis was diagnosed as an isolated finding in the second trimester. This last ultrasonographic examination was used for final analysis and as a guideline for postnatal follow-up. Neonatal outcome was assessed by reviewing medical records, ultrasonographic, renographic and voiding cysto-urethrographic results. RESULTS: Of all the fetuses diagnosed with renal pelvis dilatation in the third trimester of pregnancy, 73 (11.9%) infants needed postnatal surgery. The majority of the postnatal surgery was performed in the group of fetuses with severe hydronephrosis (8.2%). This resulted in a LR of 5.81 and a post-test probability of 61.3%. In total, 78.8% of the fetuses with hydronephrosis had spontaneous resolution across all grades of severity on the first postnatal ultrasonogaphic investigation or during their follow-up. In 9.3% of the cases, uropathies were diagnosed, but no surgical intervention had taken place during the follow-up period. Using the Corteville criteria as gold standard for the third trimester (AP ≥ 7 mm), 11 (1.8%) patients would not have been diagnosed with uropathies. And in the case of AP ≥ 10 mm, 5.1% of the cases would have been missed. CONCLUSION: An ARP of ≥ 5 mm in the second and/or third trimester of pregnancy enables a better detection of patients with uropathies and indication for surgery as compared with AP ≥ 10 mm, but renders almost similar results compared with the Cortville criteria (AP ≥ 7 mm) in the third trimester.

[Should a cystography be performed on all breastfeeding infants with mild to moderate dilatation of the urinary tract? Renal function tests can help to answer this question]. / ¿Debe realizarse una cistografía a todos los lactantes con dilatación leve y moderada de las vías urinarias? Las pruebas de función renal pueden ayudar a responder a esta pregunta.

INTRODUCTION: Pyelectasis can be defined as mild to moderate dilatation of the urinary tract and is diagnosed by means of an ultrasound scan (0.5-2cm transverse diameter in the initial ultrasound performed after birth). There is some disagreement about whether cystography should be indicated as standard practice. The aim of this study was to establish if renal function tests are useful in determining which cases of mild to moderate dilatation of the urinary tract do not require an initial cystography. PATIENTS AND METHODS: The study was conducted on 79 infants (57 males, 22 females) with pyelectasis. Seventy-three were diagnosed in utero and 6 after birth. All infants underwent at least one cystography and one desmopressin urine concentration test before one year of age. RESULTS: Compared to infants without vesicoureteral reflux (VUR) (n=68), infants with VUR (n=11; two with Grade I, three with Grade II, five with Grade III, two with Grade IV) showed a significantly lower (P=.006) maximum urine osmolality and a significantly higher microalbumin/creatinine ratio (P<.001) and NAG/creatinine ratio (P=.003). The negative predictive value of the first two tests was 93%. Sensitivity of the maximum urine osmolality to detect VUR was 72.7% (specificity 63.2%). Sensitivity of the microalbumin/creatinine ratio to detect VUR was 62.5% (specificity 75%). The positive probability ratio (PR) was 1.29 for the NAG/creatinine ratio, 2.03 for the maximum urine osmolality and 2.5 for the microalbumin/creatinine ratio. The negative PR was 0.95 for the NAG/creatinine ratio, 0.43 for the maximum urine osmolality and 0.5 for the microalbumin/creatinine ratio. CONCLUSIONS: Pyelectasis is a benign condition. Only 2 patients required pharmacological intervention (prophylactic treatment for VUR Grade IV patients). Initially at least, cystography should not be indicated in cases of microalbuminuria and/or normal urine concentrations.