The aim of the work was a retrospective evaluation of static renal scintigraphy in patients up to two years of age, who suffered from the first attack of pyelonephritis diagnosed on the basis of clinical and laboratory findings. The group of patients and method of examination: Static renal scintigraphy of kidneys by means of 99mTc-DMSA (dimercaptosuccinic acid) was performed in 35 children with the attack of acute pyelonephritis (AP) at the age of three weeks to 17 months (mean 7.2 months) in the period of 3/2001 to 5/2003. A control examination was made after 6 months in 33 children. In addition to morphological findings, the % proportion of kidney on total function (DRF) was evaluated in all patients (except a girl with agenesis of the kidney). Results: In 15/35 children (42%) with AP, static renal scintigraphy revealed a normal finding, a pathological finding in the acute phase was found in 16/35 children and a controversial finding was present in 4/35 children (11%). All patients with normal or controversial findings in the acute phase displayed normal finding during the control examination. An evolution of scar in parenchyma was demonstrated in 4/35 patients (11%). The scar was localized in the area of acute parenchymal lesion in three patients, while in one patient with the scar at the upper pole the acute phase of the disease displayed a picture of multifocal pyelonephritis. Conclusion: Based on our results renal scintigraphy by means of 99mTc- -DMSA may be recommended in suckling babies and toddlers with acute inflammation of urinary pathways, whenever the diagnosis is questionable. In patients with a normal finding in the acute phase, control examinations do not appear necessary.

        Key words: static renal scintigraphy – 99mTc-DMSA (dimercaptosuccinic acid) – pyelonephritis