Transient Nephromegaly Simulating Infantile Polycystic Disease of the Kidneys

Abstract

The discovery of bilaterally enlarged kidneys near the time of birth often portends a poor prognosis for renal function. Important diagnostic considerations include obstructive uropathy; renal venous thromboses; Wilms’ tumor; infantile polycystic kidney disease, and renal multicystic dysplasia. In this report, we describe a child in whom enlarged bilateral kidneys were noted during the first day of life and to whom a presumptive clinical diagnosis of infantile polycystic kidney disease was incorrectly assigned, primarily on the basis of the excretory urogram. By 6 weeks of age, however, the kidney size was normal, and at 2 years of age, the boy remains in good health with radiographically normal kidneys.

Case Details

Personal Characteristics

A white male infant WHO weighed 4,460 grams at birth. His mother was 19 years old, gravida 1, para 0. The mother denied taking any medications, except prenatal vitamins and iron, during the pregnancy. There was no family history of renal disease, hypertension, liver disease, early deaths, or cerebral vascular accidents. The parents were not related.

Clinical Characteristics

Enlarged bilateral kidneys noted during the first day of life. Physical examination revealed smooth, rounded flank masses that did not transilluminate. The right flank mass measured approximately 5 x 1 1/2 centimeters and the left mass measured 4 x 1 1/2 centimeters. The systolic blood pressure was 76 mmhg by doppler ultrasound. The remainder of the examination was normal, and urine output was normal. Results of the urinalysis were: ph 6, proteinuria (3+), negative glucose, negative hemoglobin, 0 to 1 white blood cells, and 0 to 2 red blood cells/high power field.

Remission Characteristics

By 6 weeks of age, the kidney size was normal, and at 2 years of age, the boy remains in good health with radiographically normal kidneys.

Treatment & Mechanisms

Proposed Remission Mechanisms

Not discussed

Additional Notes

A presumptive clinical diagnosis of infantile polycystic kidney disease was incorrectly assigned, primarily on the basis of the excretory urogram.