Congenital Anomalies of the Kidney and Urinary Tract (CAKUT)

Functional MR urography in children - update 2023

BACKGROUND

Functional MR urography (fMRU) has developed into an innovative, radiation-free option for assessing parameters of kidney function in pediatric radiology. The importance of fMRU in comparison to the standardized established nuclear medicine procedure (99mTc-Mercapto-acetyltriglycerine, MAG3 scintigraphy) is shown using SWOT analysis.

METHODS

To assess the current state of research, a selective literature search was carried out in PubMed. Taking into account the current scientific status, the examination technique, preparation, and evaluation of fMRU are presented.

RESULTS

As a result of the comparison with MAG3, fMRU is suitable for certain indications and represents an optimal combination of morphological and functional representation of the kidneys and urinary tract, especially in the case of surgical consequences.

CONCLUSION

fMRU has been successfully established as a diagnostic method for assessing the morphology and function of the kidneys in competition with MAG3 scintigraphy.

KEY POINTS

· Functional MRU allows reliable statements on the morphology and function of the kidneys and urinary tract.. · The results of the functional assessment of fMRU are comparable to the results of MAG3 scintigraphy.. · The complex implementation and demanding evaluation limits the spread of fMRU as a complete alternative to MAG3 scintigraphy. fMRU is reserved for special indications.. · Functional MRU has prevailed over MAG3 scintigraphy for complex renal and urinary tract anomalies (CAKUT) that require surgical correction. An example is the clarification of dribbling in girls, which is usually based on an ectopic opening of a ureter in a double system..

CITATION FORMAT

· Kirsch H, Krüger P, John-Kroegel U et al. Functional MR urography in children - update 2023. Fortschr Röntgenstr 2023; 195: 1097 - 1105.

Prevalence, types, and malformations in congenital anomalies of the kidney and urinary tract in newborns: a retrospective hospital-based study

Background

Congenital anomalies of the kidney and urinary tract (CAKUTs) are some of the most common birth defects affecting newborns. CAKUTs often have poor birth outcomes owing to the limited experience of physicians in developing countries regarding antenatal and postnatal diagnosis. We aimed to estimate the epidemiology of CAKUTs using data from a hospital-based registry in Zhejiang Province, China.

Methods

We included a total of 2790 newborns with CAKUTs, identified among 1,748,038 births during 2010–2016. The prevalence and type of CAKUTs, maternal and neonatal characteristics, and associated malformations were analyzed.

Results

The average prevalence of CAKUTs born to mothers overall and mothers aged ≥35 years were both around 1.60 per 1000 births (95% confidence interval (CI), 1.54–1.66; 95% CI, 1.44–1.83, respectively) during the study period. The prevalence of CAKUTs changed over time among all women and women of advanced maternal age, although no significant trends were observed. CAKUTs were more likely to occur in male than female newborns (odds ratio (OR) 1.28, 95% CI 1.18–1.38), in multiple births than singletons (OR 1.53, 95% CI 1.21–1.92) and in urban areas than rural areas (OR 1.27, 95% CI 1.18–1.37). The overall prenatal detection rate of CAKUTs was 73.87%. The average gestational age at antenatal diagnosis was 26.57 ± 8.70 weeks. A total 22.69% CAKUTs had associated malformations. Congenital heart defects were the most common anomalies, accounting for 8.89% of the whole population. The main proportion in subgroups was hydronephrosis, representing 31.79% of registered CAKUTs.

Conclusions

There was a nearly twofold increase in the prevalence of CAKUTs from 2010 to 2016 in Zhejiang Province. CAKUTs are strongly associated with male sex, multiple births, urban areas, and other nonurinary congenital malformations.