Relevance Recent studies show an increased incidence of urolithiasis in children, including the age of first few months of life. Extracorporeal shock wave lithotripsy (ESWL) with focused shock waves is a fundamentally new method of treatment of urolithiasis in children. With employing ESWL method the calculus destruction in the kidney can not be achieved wihout an impact on kidney parenchyma. Shock wave in ESWL affects also a contralateral kidney.

Objective To evaluate renal parenchyma condition before and after ESWL in children with urolithiasis by using dynamic renal scintigraphy

Patients and methods We analysed dynamic renal scintigraphy results in children with urolithiasis before and after single session of ESWL. In dynamic renal scintigraphy we included angiographic phase, evaluation of the parenchyma and urodynamics. We applied a quantitative assessment of the overall state of perfusion and renal function, also we detected local areas of microcirculation impairement and disturbances of nuclear isotope transport in parenchyma.

Results In the early period after ESWL in comparsion to pre-ESWL state we observed transportation delay in kidney parenchyma without changing or with a degree of slowing down in urodynamics of the affected kidney and improvement in all indicators for contralteral kidney. In the period from 5th to 14th days urodynamics and transportation indicators in the affected kidney became normal, and in the contralateral kidney they came in original state. Microcirculation impairement in response to ESWL was not identified in any of the kidneys.

Conclusion An observed functional impairment was associated with an initial state of kidneys. The impact of ESWL to a healthy kidney can be seen as a kind of ’stress test’ which gives us an opportunity to determine the presence of active and hidden (’sleeping’) nephrons comprising renal functional reserve. Dynamic renal scintigraphy showed high diagnostic value in urolithiasis in children, and it is a mandatory in modern urological examination. This method is minimally invasive and does not require any sedation and is easy to carry out in children.