Unilateral Hydronephrosis

Unilateral hydronephrosis consists of dilation of a single kidney due to a buildup of urine, almost always because there is an obstacle that impedes its drainage toward the bladder. Because it involves only one kidney, the other usually compensates, though it still warrants evaluation.

Common causes: urinary stones, narrowing of the ducts, abnormalities present from birth, or external compressions that hinder the passage of urine.

Possible symptoms: pain on one side of the back, discomfort when urinating, or urinary tract infections; in many cases it is identified incidentally on an ultrasound.

Who to see? The nephrologist and the urologist guide the diagnosis, and in childhood the pediatric nephrologist along with the pediatrician. In the face of persistent lower back pain or urinary changes, it is worthwhile to seek guidance from a specialist.