Fetal pyelectasis

What it means

Mild pyelectasis is defined as a hypoechoic spherical or elliptical space within the renal pelvis that measures at least 5mm and not more than 10 mm. The measurement is taken on a transverse section through the fetal renal pelvis using the maximum anterior-to-posterior measurement.

The renal pelvis is the part of the kidney that collects urine. Fetal pyelectasis is a prenatal ultrasound finding that is diagnosed with enlargement of the renal pelvis from 4 to 10 millimeters. In many cases, fetal pyelectasis resolves spontaneously. Note that dilatation of the renal pelvis to more than 10 mm is referred to as severe pyelectasis or hydronephrosis. Measurements less than 5mm are normal, should not be designated as pyelectasis, and should not be reported (PMID:16100637).

Rare diseases that can present with this6

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Fetal renal pelvic dilatation · Foetal pyelectasis · Foetal renal pelvic dilatation · Mild fetal hydronephrosis · Mild foetal hydronephrosis