Focal and diffuse increased echogenicity in the renal parenchyma in patients with sickle hemoglobinopathies--an observation

Eleven patients with sickle hemoglobinopathies undergoing sonographic examinations for reasons unrelated to renal parenchymal disease were incidentally noted to have increased echogenicity in the central portion of the renal parenchyma. This appearance was observed to be a continuum, with some cases showing focally hyperechoic medullary pyramids at one extreme and other cases showing a diffusely echogenic central parenchymal region relative to a thin band of hypoechoic cortical or peripheral parenchyma at the other extreme. The finding of hyperechoic medullae of the kidneys has been reported in patients having conditions associated with hyperuricemia, medullary nephrocalcinosis, or hypokalemia. This sign has not been commonly reported as a finding in patients with sickle syndrome. The thin hypoechoic rim of cortical parenchyma relative to a more echogenic central parenchyma has not been commented on previously.