Transient pyelonephritic changes on 99mTechnetium-dimercaptosuccinic acid scan for at least five months after infection.
A prospective study was performed on 185 children with symptomatic urinary tract infection (UTI), 130F and 55M, having a median age of 0.9 y (range 0.1-9.8) at the time of UTI. The aim of the study was to find out how the 99mTechnetium-dimercaptosuccinic acid (DMSA) scan should be used to investigate UTI, and to follow the development of renal changes during pyelonephritis into subsequent permanent renal damage. All children were investigated with a DMSA scan within 5 days after admission and after 3.9-53.3 (median 9.2) weeks, and 159 were studied again after approximately 2 y (range 1.5-3.9 y). They all underwent micturition cystourethrography at the time of the second study. At the time of infection, the DMSA scan was abnormal in 85% of the children, in 58% at the first follow-up and in 36% at the second follow-up. An abnormal DMSA scan performed within 20 weeks from infection became normal in 38% of cases on the third study, while only 1/10 abnormal DMSA scans performed more than 20 weeks after infection became normal after 1.5-3.9 y. Persistent renal changes were more common in children > 4 y of age than in children < or = 1 y of age. Two months after the presenting infection, it was unusual to see a normal DMSA scan in a child with a VUR gr. > or = 3. The study suggests that DMSA changes after an index UTI may be transient for a longer period of time than has been previously considered. Therefore, in order to detect persistent changes, a DMSA scan should be performed more than 5 months after UTI.
Jakobsson
B
B
Department of Pediatrics and Nuclear Medicine, Karolinska Institute, Huddinge University Hospital, Sweden.
Svensson
L
L
D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007668:Kidney / Q000000981:diagnostic imaging*; D008297:Male; D015609:Organotechnetium Compounds; D011446:Prospective Studies; D011704:Pyelonephritis / Q000000981:diagnostic imaging*; D011877:Radionuclide Imaging; D012008:Recurrence; D004113:Succimer; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D013997:Time Factors; D014552:Urinary Tract Infections / Q000000981:diagnostic imaging*; D014567:Urography
D015609:Organotechnetium Compounds; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D004113:Succimer