ESPN 51th Annual Meeting

ESPN 2018


 
Urine interleukin-6 as marker of acute pyelonephritis in febrile infants
CRISTINA JULIA BLAZQUEZ GOMEZ 1 FLOR ANGEL ORDOƑEZ 1 LEIRE CARDO 1 BELEN FERNANDEZ-LLANA 1 AGUSTINA ALONSO 1 FERNANDO SANTOS 1

1- Hospital Universitario Central de Asturias
 
Introduction:

Renal 99mTc-DMSA scan is considered the "gold standard" test in the diagnosis of acute pyelonephritis (APN) but its usefulness in the everyday clinical practice is quite limited. No suitable biological surrogate indicative of APN is available.  The purpose of this study was to evaluate the utility of interleukin-6 (IL-6) as a biomarker of APN in infants.

Material and methods:

In a prospective study, infants aged from 1 to 24 months with fever and leukocyturia seen in the pediatric emergency room of our hospital from April 2015 to November 2017 were included. Exclusion criteria: former diagnosis of congenital nephrourological abnormality, medical history of nephropathy, acute kidney failure, previous antibiotic therapy, severe systemic involvement. Serum and urine IL-6 concentrations were measured when the patients were first seen (T1) and 12-24 hours later (T2). A renal 99mTc-DMSA scan was performed in the first 48 hours. The results were compared according to the presence (group 1) or absence (group 2) of findings of APN in DMSA gammagraphy. Six months later, approximately, DMSA scan was repeated in group 1 to find out persistent kidney scars

Results:

Twenty-five children (48% girls) aged 5.9±5.9 months were included.  Fifteen in group 1 and 10 in group 2. No differences were found (p> 0.05) in the absolute values of serum and urine IL-6 concentrations between both groups. However, the urine IL-6/creatinine ratio (pg/mg) tended to be higher in the group 1 on T1 (12.21±16.27 vs 7.85±10.08, p>0.05) and was clearly and significantly (p<0.05) higher on T2 (17.3±18.24 vs 3.88±3.57). The area under the curve for the urine IL-6/creatinine was 0.64, the optimal cut-off level of IL6/creatinine was 4.8 pg/mg ,sensitivity of 72.7% and specificity of 60%.

Conclusions:

 The urine IL-6/creatinine could help to the early identification of APN in febrile infants.