Background and Aims The aim of this study was to evaluate the usefulness of Procalcitonin(PCT) as a marker for renal scars in infants with a first febrile urinary tract infection(UTI).
DMSA scintigraphy, the gold standard for detection of cortical scarring, has clearly shown that not all febrile UTI are associated with renal lesions and that common clinical and laboratory evaluations are not reliable to distinguish between acute pyelonephritis(APN) and simple UTI. Scarring secondary to APN is a common event occurring in approximately 30% of all cases.
PCT, prohormone of calcitonin has been measured in various systemic inflammatory response syndromes, because it appears to be correlated with the severity of microbial invasion and it can be used to check for the presence of parenquimal scars.
Methods This prospective study includes 140 children less than 2 years, 64% females admitted for febrile UTI. PCT levels were measured at diagnosis and DMSA scan at the 6 months. We use a study of diagnostic test assessing their sensitivity and specificity. ROC curve was performed.
Results Abnormal DMSA was found in 14 infants (11.3%). Using a cutoff value of 0.6ng/ml. PCT sensitivity for detect renal scars on DMSA was 57.1% (95%CI, 31.2–83.1%) and specificity was 56.1% (95%CI, 46.7–65.5%). Negative predictive value was 90.9% (95%CI, 84–97.8%). AUC (area under curve) is 0.582.
Conclusions We can conclude that PCT yelds a high negative predictive value of renal damage. Therefore a low PCT value at the time of admission points out a low risk of renal scarring.