Home HealthTopics Health Centers Reference Library Research
Join us on Facebook Join us on Facebook Share on Facebook

Urinary and Genital Disorders (Children)

Bilateral Calyceal

08/27/2009

Question:

At 23 weeks the ultrasound showed "bilateral calyceal renal size of 5 - 6 mm". The amniotic fluid volume is normal and the second trimester prenatal screening results were normal/negative. What does "bilateral calyceal renal size of 5 - 6 mm" mean; and how serious is this? Does this mean my baby may have genetic abnormalities?

Answer:

Having some degree of renal pelvic dilation is very common in unborn babies, and affects as many as 1 in 50 to 1 in 100. The degree of enlargement of dilation is mild, and probably not significant. However, following delivery, it is important to obtain a follow-up sonogram, ideally after 48 to 72 hours, to be certain that the kidneys are normal. Often this finding results from a mild kink in the upper ureter, but in some cases it results from severe urinary backflow from the bladder to the kidneys. In the majority of cases the swelling resolves and there is no need for exploration or surgery to repair an obstructed ureter.

For more information:

Go to the Urinary and Genital Disorders (Children) health topic, where you can:

Response by:

Jack S Elder, MD, FACS, FAAP Jack S Elder, MD, FACS, FAAP
Clinical Professor of Urology
School of Medicine
Case Western Reserve University