Antenatal Diagnosis of Renal Tract Anomalies: Has it Increased the Sum of Human Happiness?

Comparative effectiveness of a pilot patient-centered ultrasound report in the management of hydronephrosis

PURPOSE

Hydronephrosis is a common pediatric abnormality and can be associated with substantial parental anxiety, especially in the prenatal period. Radiology reports contain complex content that can be difficult for lay audiences to comprehend, potentially contributing to parental distress.

MATERIALS AND METHODS

We developed and piloted a patient-centered radiology report (PCRR) for renal ultrasounds (US) in children with hydronephrosis (Figure). We obtained consensus from a multidisciplinary panel of experts regarding critical US report components. A parent focus group provided input regarding syntax and formatting of a PCRR, incorporating elements deemed valuable by the expert panel. We prospectively recruited parents of children who underwent US for hydronephrosis and randomized parents to receive either the PCRR + standard report (SR) or SR alone. Web-based surveys assessed self-efficacy and knowledge of US elements.

RESULTS

Our pilot study included 20 SR patients and 24 PCRR patients, with no difference in demographic or disease characteristics between groups. Self-efficacy scores were uniformly high in both groups (p = 0.79). PCRR parents trended towards increased accuracy in identifying presence of severity (88% vs. 70%; p = 0.15) and bilaterality (67% vs. 45%; p = 0.15), with minimal difference in identifying parenchymal pathology (75% vs. 70%; p = 0.71) and bladder abnormalities (88% vs. 85%; p = 0.81). Parents were more confident in their ability to understand the PCRR (92% vs. 60%; p = 0.01).

CONCLUSIONS

A PCRR was associated with significantly higher confidence in US report interpretation, but was underpowered to demonstrate increased accuracy in identifying US findings. These findings justify future studies of PCRRs for hydronephrosis care.

Antenatal and postnatal ultrasound in the evaluation of the risk of vesicoureteral reflux

Antenatal hydronephrosis (ANH) is a frequent anomaly detected on fetal ultrasound scans. There is no consensus recommendation for the postnatal follow-up and/or the necessity to perform a voiding cystourethrography (VCUG) to diagnose vesicoureteral reflux (VUR). We conducted a cohort/non-randomized trial of 121 patients with ANH, defined as an anterior posterior diameter (APD) >or=5 mm after the 20th week of gestation, to evaluate the ability of the antenatal and postnatal ultrasonography results to predict VUR. All infants had two successive ultrasounds at 5 days and 1 month, respectively, after birth. A VCUG was performed at 6 weeks in children with a persistent APD >or=5 mm and/or an ureteral dilatation observed on at least one of two postnatal ultrasounds. In total, 88 patients had VCUG and nine had VUR, with five having high-grade reflux (>grade II). The risk of VUR increased significantly with the degree of APD detected on the postnatal ultrasound scan (p = 0.03). The odds ratios were 5.0 [95% confidence interval (CI) 0.5-51.2] for APD = 7-9 mm and 9.1 (95% CI 1.0-80.9) for APD >or=10 mm. The results of this study show that among our patient cohort antenatal ultrasound was not predictive of reflux. There was, however, a relation between the importance of the postnatal renal pelvis diameter and the risk of VUR. A cut-off of 7 mm showed a fair ability of ultrasonography to predict VUR and a cut-off of 10 mm enabled all severe refluxes in the 88 patients who had a VCUG to be diagnosed.

Micturating cystourethrograms are not necessary for all cases of antenatally diagnosed hydronephrosis

OBJECTIVE

Since 1995 we have, at our centre, adopted a selective approach to performing micturating cystourethrograms (MCUGs) on patients with antenatally diagnosed hydronephrosis. This study reviews the outcome of this policy.

METHODS

We carry out MCUGs only if any of the following features are present on ultrasound: bilateral hydronephrosis, ureteric dilatation, renal scarring, bladder wall thickness greater than 5mm, or presence of a duplex system or ureterocele. Patients with simple unilateral hydronephrosis are excluded, and are managed with 6 months' trimethoprim prophylaxis and ultrasound surveillance with a minimum of 3 years' follow up.

RESULTS

Fifty-five patients were referred with an antenatal diagnosis of hydronephrosis between 1999 and 2002; 26 (47%) did not have an MCUG. Of these, five had increasing hydronephrosis and required surgery for pelvi-ureteric junction obstruction, and three had a multicystic dysplastic kidney on postnatal scanning. In the remaining 18 patients, the hydronephrosis resolved spontaneously, with no renal scars or asymmetry. During follow up, none of these patients had a urinary tract infection.

CONCLUSION

We believe that vesico-ureteric reflux in most antenatally diagnosed hydronephrotic kidneys is physiological rather than pathological, and resolves with time without causing long-term renal damage. This is a separate entity from, rather than a precursor of, the pathological symptomatic refluxing kidney in older, mainly female children. Taking a more conservative approach to the postnatal investigation of antenatally diagnosed hydronephrotic kidneys has not resulted in any missed damaged kidneys, but has reduced the number of invasive investigations performed. A careful protocol and detailed postnatal ultrasonography are important to prevent missed pathological cases.

Prenatal diagnosis and management of mild fetal pyelectasis: implications for neonatal outcome and follow-up

OBJECTIVES

To describe the natural history of pyelectasis from its detection in the second trimester to delivery, its capability to predict renal pathology and whether prenatal development of pelvic dilatation is correlated to its postnatal evolution.

STUDY DESIGN

A retrospective analysis involving 375 fetuses with a complete urological follow-up. Prenatal ultrasound was correlated with the results of postnatal investigation and frequency of postnatal surgery was established.

RESULTS

Two-hundred and eighty cases underwent at least two examinations before birth. 73.1% were male fetuses. 57.4% had a bilateral pyelectasis. Prenatal evolution of pelvic dilatation was the following:18.6% of the cases normalized, in 34.6% of the cases the dilatation reduced but did not disappear, in 30.7% it remained unchanged, while it worsened in 16.4%. One case from the first group, three cases from the second, seven cases from the third and 11 cases from the fourth needed surgical treatment. 1.9, 7.2, 18.6, 23.9% of cases respectively worsened after birth in the four groups (trend: P=0.001).

CONCLUSIONS

Prenatal diagnosis of pyelectasis improves the outcome of these children due to a surgical approach that avoids renal damage. There is a good correlation between prenatal evolution and postnatal outcome, although a postnatal follow-up is opportune in those cases that normalized before birth.

Ultrasound screening in pregnancy: advancing technology, soft markers for fetal chromosomal aberrations, and unacknowledged ethical dilemmas

Fetal ultrasound screening has become routine practice in many western countries. During the last decade, such screening has led to frequent situations characterised by clinical uncertainty due to the disclosure of soft markers in the unborn child. Soft markers are minor anatomical variations indicating a somewhat increased likelihood that the fetus has a chromosomal aberration, most frequently trisomy 21 (Down syndrome). This paper presents the results of a comprehensive literature search of the National Library of Medicine with emphasis on the chronological development of scientific knowledge in relation to soft markers and the link between advancing imaging technology and clinical counselling dilemmas. An analysis of the literature makes evident that many ultrasound examiners have counselled individual pregnant women on the basis of insufficient data. Moral dilemmas have thus emerged as a direct result of advancing medical technology, and healthy fetal lives prove to have been lost due to invasive diagnostic testing aimed at resolving clinical uncertainty. Ultrasound examiners have warned against a policy of disclosing all findings of soft markers to expectant parents, but no exploration of experiential aspects linked to the disclosure of fetal soft markers has yet been published in the medical literature. The emotional reactions of mothers are important to consider given their potential impact on the biological development of the fetus. In conclusion, this paper stresses the need for paying close attention to the crucial distinction between technology development and technology implementation in relation to prenatal testing. Furthermore, it provides strong arguments for scrutinising the interface between prenatal testing and human experience.

On the value-ladenness of technology in medicine

The objective of this article is to analyse the value-ladenness of technology in the context of medicine. To address this issue several characteristics of technology are investigated: i). its interventive capacity, ii). its expansiveness and iii). its influence on the concept of disease, iv). its generalising character, v). its independence of the subjective experience of the patient. By this analysis I hope to unveil the double face of technology: Technology has a Janus-face in modern medicine, and the opposite of its factual face is evaluative.

Antenatal minimal hydronephrosis: is its follow-up an unnecessary cause of concern?

The aim of this study was to determine if follow-up of antenatally diagnosed minimal hydronephrosis (anteroposterior renal pelvis diameter <10 mm) is justified or if it is an unnecessary cause of concern for the parents involved. A case-control study, with subjects and controls selected from the Wessex Antenatally Detected Anomalies Register was performed. Information regarding antenatal and postnatal follow-up, renal tract morbidity and degree of concern was obtained from a parental questionnaire. 70 of the 115 subjects contacted (60.9 per cent) and 52 of the 81 controls (64.2 per cent) returned the questionnaire. 65 of the 70 subjects (92.9 per cent) were rescanned postnatally when 28 cases (43.1 per cent) had resolved. Coexisting ureteric and/or calyceal dilatation was evident postnatally in 12 cases and this group was significantly more likely to have underlying pathology than the group with isolated renal pelvis dilatation. Subjects were significantly more likely than controls to have a UTI. The degree of concern was significantly greater in the subject group and subject parents thought about the result significantly more often than controls. From our results we concluded that the follow-up of minimal hydronephrosis can be modified. There is no need for repeated antenatal scanning, a change that could reduce the level of parental anxiety. Postnatal follow-up is required in all patients to exclude an underlying uropathy but again this can be modified, with the majority of patients requiring only an ultrasound scan. This reduced intensity of investigation accompanied with careful explanation to the parents should help to minimize their concerns.

Development of human fetal kidney in obstructive uropathy: correlations with ultrasonography and urine biochemistry

In utero urethral obstruction results in bilateral hydronephrosis and severe fetal and post-natal morbidity and mortality. Obstetrical management depends on the indirect evaluation of fetal renal function by ultrasonography and biochemical analysis. No direct evaluation of the severity and possible reversibility of renal lesions is available. In this paper we analyzed kidneys from 34 fetuses (14 to 37 gestational weeks) in which (1) isolated bilateral urinary tract obstruction had been detected in utero by sonography, and (2) the severity of sonographic and biochemical prognostic indicators led to the indication of termination of pregnancy or to perinatal death. Pure hydronephrosis was observed in two young fetuses [14 and 20 gestational weeks (GW)] and was associated with regressive changes in two others. In contrast, a wide spectrum of dysplastic renal lesions was present in 30 fetuses and was classified into four subgroups according to the association of dysplasia, hypoplasia and cysts. They had the following characteristics in common: (1) premature cessation of nephrogenesis assessed by the medullary ray counting method; (2) early disappearance or myofibroblastic differentiation of metanephric blastema; (3) early increase in interstitial mesenchyme with widespread expression of alpha-smooth muscle actin by mesenchymal cells; (4) frequent absence of classical criteria of dysplasia (nests of cartilage were observed in only 5 fetuses); (5) an identification, based upon the detection of alpha-smooth muscle actin expression, of the muscular phenotype of mesenchymal cells encircling primitive ducts. In conclusion, (1) the value of prognostic markers in fetuses less than 20 GW should be reconsidered; (2) after 20 GW there is a good correlation between markers predicting poor prognosis and the severity of renal lesions; (3) hypoplasia with disappearance of blastema cells, dysplasia and early interstitial fibrosis are evidence of the irreversibility of renal lesions and preclude any possibility of new nephron formation; (4) these findings suggest that most surgical in utero procedures are performed when irreversible renal lesions have developed.