Fernández-Menéndez JM, Málaga S, Matesanz JL, Solís G, Alonso S, Pérez-Méndez C. Risk factors in the development of early technetium-99m dimercaptosuccinic acid renal scintigraphy lesions during first urinary tract infection in children. Acta Paediatr 2003; 92: 21-26. Stockholm. ISSN 0803-5253Aim: To establish the variables that correlate with uptake defects in dimercaptosuccinic acid (DMSA) scintigraphy performed in the acute phase of a first episode of urinary tract infection (UTI). Methods: A prospective observational study was conducted in a cohort of 158 consecutive children with a first episode of symptomatic UTI. The therapeutic delay time (TDT) was recorded. DMSA scintigraphy was performed in all children and voiding cystourethrography in 150 of them. Results: 85% of the patients were younger than 2 y. Mean TDT was 33.5 h. The aetiological agent was Escherichia coli in 140 children. DMSA scintigraphy was normal in 81. Vesicoureteric reflux was detected in 33. After a multivariate logistic regression analysis the following variables were retained in the final model: TDT !48 h, growth of bacteria other than E. coli, percentage of polymorphonuclear cells !60% and C-reactive protein !30 mg l À1 .Conclusion: TDT !48 h, bacteria other than E. coli, percentage of polymorphonuclear cells !60% and CRP !30 mg l À1 influence the findings detected in the DMSA scintigraphy performed in the acute phase of a first episode of UTI.

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