Serum Procalcitonin and Early Prediction of Renal Parenchymal Involvement in a Pediatric Patient with a Urinary Tract Infection

Patient selection: child with a first episode of urinary tract infection, age 2 to 108 months

Clinical and laboratory findings associated with renal parenchymal involvement (RPI):

(1) body temperature >= 38°C

(2) history of diarrhea

(3) poor oral intake

(4) elevated ESR (>= 25 mm/h had a sensitivity of 100% and specificity 70%)

(5) elevated serum C-reactive protein

(6) elevated serum procalcitonin

Cutoff for serum procalcitonin: >= 0.85 ng/mL

Performance at cutoff: sensitivity of 89%, specificity 97%, area under ROC curve 0.99.