RENAL DYSPLASIA IN INFANTS - APPEARANCE ON TC-99M DMSA SCINTIGRAPHY

Infantile renal dysplasias, including multicystic dysplastic kidneys (MCDK), are reported rarely to accumulate radiopharmaceuticals on renal scintigraphy. Te-99m DMSA is a highly sensitive tracer for detecting functioning renal cortical tissue and may be more suited to studying renal dysplasia than Te-99m DTPA. We reviewed the ultrasound studies and Tc-99m DMSA scintigrams of 42 infants (age range 1-12 months) with known or suspected MCDK. Overall, uptake on Tc-99m DMSA scintigraphy was evident in 6/41 (15%) dysplastic kidneys. Of the 18 patients who underwent nephrectomy, histopathological examination revealed that uptake correlated closely with the presence of mature renal cortical tissue in the affected kidney. Our study shows that a small, but significant number of MCDK will show low-grade uptake on DMSA scintigraphy. This finding may be relevant given the reliance placed on renal scintigraphy in planning treatment for infants with suspected MCDK, particularly with the increasing trend for the non-operative management of this condition.