Renal involvement in children with lymphoma: comparison of CT with sonography

In order to determine whether real-time sonography or contrast-enhanced CT was better for detecting renal involvement by lymphoma in children, we retrospectively studied 44 patients (6 months to 19 years of age) in whom lymphoma was diagnosed at our hospital during a 5-year period. In no patient was there any clinical evidence of renal disease at the time of presentation. In 39 patients, sonographic and CT findings were similar (normal in 36 patients and showing extrinsic mass effects on the kidneys in three patients). In five patients with non-Hodgkin lymphoma whose contrast-enhanced CT scans showed low-attenuation renal nodules, renal sonography was normal in two, showed renal enlargement in two, and showed a solitary hypoechoic nodule in one patient with multiple, bilateral nodules on CT. Tissue diagnosis of the renal lesions was not obtained, but in the four patients who had follow-up CT, the renal abnormalities resolved after chemotherapy. Our findings suggest that contrast-enhanced CT is superior to sonography for detection of renal lymphoma in children.