Hydronephrosis
Hydronephrosis is dilatation of the renal collecting system, usually caused by impaired urine drainage; localise the cause, protect renal function, and treat an infected obstructed kidney as a urological emergency.
Definition
Hydronephrosis is dilatation of the renal pelvis and calyces caused by impaired drainage, reflux, congenital anatomy or a persistent non-obstructive dilated system. Hydroureter is associated ureteric dilatation.
First principles
Hydronephrosis is a sign, not the cause
Dilatation of the renal pelvis and calyces may reflect obstruction, reflux, congenital anatomy, pregnancy or persistent dilatation after a previous obstruction. The result must therefore be interpreted with symptoms, renal function, bladder findings and the clinical context rather than treated as a diagnosis by itself.
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