Sonographic findings in familial juvenile nephronophthisis-medullary cystic disease complex

Familial juvenile nephronophthisis-medullary cystic disease complex (JN-MCD) is an autosomal inherited renal disease with insidious symptoms that ultimately progresses to renal failure. We describe the abnormal sonographic findings in JN-MCD at various stages of the disease in a Taiwanese family.

We collected 8 cases in a family via 2 symptomatic index siblings. The affected members were 4 males and 4 females whose ages at diagnosis ranged from 1 to 39 years (mean, 16.8 years). Serial sonographic examinations were performed.

There were 4 abnormal findings: renal hyperechogenicity, poor corticomedullary differentiation, small kidney size, and corticomedullary cysts. Renal hyperechogenicity and poor corticomedullary differentiation were found in all cases. Renal cysts and reduced renal size sometimes appeared later, after the disease had progressed. Three cases had no visualized cysts.

Because abnormal renal sonographic findings can be seen long before the appearance of any clinical symptoms or signs, sonography is the best technique for diagnosing JN-MCD and for screening a patient's family.