Prenatal failure to visualize kidneys: a spectrum of disease

To better understand the outcomes and management of patients when there is a failure to visualize kidneys on prenatal ultrasound.

Nine thousand five hundred twelve prenatal ultrasound studies performed on 4900 patients were reviewed retrospectively for the findings of a failure to visualize kidneys. The prenatal ultrasounds, pregnancy outcomes, and postmortem studies were reviewed for each of the 10 patients identified.

Nine of 10 patients experienced fetal death in the index pregnancy: 7 had therapeutic abortions, 1 had an intrauterine fetal demise, and 1 gave birth to a stillborn infant. One patient gave birth to a live infant with Bartter's syndrome and grossly normal kidneys, as diagnosed by ultrasound. Developmental renal anomalies were identified in only 4 of 10 cases, and only 2 patients had true bilateral renal agenesis. There was 1 case each of bilateral renal medullary cystic dysplasia and bilateral renal hypoplasia. Three cases had no renal anomalies and included 1 case each of Turner's syndrome, chronic abruption, and a cord accident. In 2 cases, postmortem examinations were not performed because of family wishes.

Prenatal failure to visualize kidneys represents a spectrum of clinical problems not all of which are fatal. Close consultation with an experienced ultrasonographer is essential to provide informed counseling to expectant parents. Pathologic examination should be recommended when there is fetal demise and a suspicion of genitourinary anomalies. Screening of family members of the index patient and genetic counseling may be indicated.