First Urinary Tract Infection Episode in Children: Are Procalcitonin Values & US Examination of Importance in the Diagnosis of Upper Urinary Tract Infection ?

1. “ First urinary tract infection episode in children:
Are procalcitonin values
& ultrasound examination of importance
in the diagnosis of upper urinary tract infection ? ”
S.P. Deftereos, A. Kotoula, E. Vranou, A. Zisimopoulos, A. Chadjimichail, P. Prassopoulos
Democritus University of Thrace, Department of Radiology, Alexandroupolis, Greece

2. URINARY TRACT INFECTIONS
 Differential diagnosis
between upper and
lower urinary tract
infection
 Acute pyelonefritis
 Scars  Hypertension
 C.R.D

3. GENERAL APPROACH until today…
Clinical evaluation
Temperature ≥38oC, presence of vomiting or
diarrhea, decreased oral intake

Laboratory investigation
 ESR, CRP, leukocyte count, positive culture
of urine speciment

4.  116-amino-acid propeptide
of calcitonin
 New marker of bacterial
infections
 Under physiological
conditions undetectable
 Very high levels in
response to bacterial
infections
 Decreases within 48h of the
administration of antibiotics
PROCALCITONIN (PCT)

5. DMSA
Gold standard method but
Costs
Limit availability
Inability to differentiate old scarring
from acute
Exposure of patients to radiation
ULTRASOUND
Noninvasive with no risk to
the patient
Easily performed method
No exposure to radiation but
 Strongly dependent on the operator
 Children are not always cooperative
VCUG
Information for VUR but
Performed after UTI treatment
Radiation exposure (gonads)
Invasive method

6. DMSA
ULTRASOUND
PCT
WBC
ESR
CRP
UUTI

7. AIM
To examine the efficacy of ultrasonography
(US) findings in combination with
procalcitonin (PCT) values in predicting renal
parenchymal involvement (RPI) in children
with urinary tract infection (UTI)

8. PATIENTS AND METHODS
Prospective study
57 children (mean age: 12months, range: 2 -
108months)
First episode of UTI
Children with a history of prior UTI were not included
N=43 N=14

9. Clinical evaluation:
 Temperature ≥38oC, vomiting / diarrhea,
decrease oral intake
Laboratory investigation includes:
 Urine specimens culture
 Leukocyte count
 Erythrocyte sedimentation rate (ESR)
 C-reactive protein (CRP) and
 serum PCT
PATIENTS AND METHODS

10. Imaging evaluation includes:
US: within 48h
DMSA: within 7 days and
VCUG: after 4-5 weeks (n:51/57pts)
A follow up DMSA was performed after 6 months to
examine possible persistent renal lesions
PATIENTS AND METHODS

11. RESULTS
 Upper UTI (group A, n: 27 children)
DMSA positive, abnormal US (n=15, 55.6%)
 Lower UTI (group B, n: 30 children)
DMSA negative, US no abnormalities
(except 4 pts with urinary bladder thickening)
N=8
N=21
N=18
N=12
N=27 N=30
PCT
+
+

12. DMSA + US +
Follow Up
RESULTS

13. RESULTS

14. Hyperechoic renal parenchyma
Collecting system dilatation
Increased total kidney volume
Scars (congenital, others)
CDS- irregular vascularity
ULTRASOUND FINDINGS

15. All infection markers, except LC, have the same diagnostic value
PROGNOSTIC VALUE ?
Group A (N=27) median (range) Group B (N=30) median (range) P value
Leukocyte count (/μl) 19,000 (8,000-27,000) 12,750 (4,500-23,500) 0.056
ESR (mm/h) 40 (27-98) 17.5 (2-75) <0.001
CRP (mg/dl) 9 (1.9-35) 0.5 (0.1-6.5) <0.001
PCT (ng/ml) 4.8 (0.5-13.2) 0.3 (0.1-0.9) <0.001
RESULTS

16. PCT levels were significantly higher in patients with
persistent renal lesions or/and VUR (n=8) * than in those
with total regression of RPI (n=15) (p=0,004)
*Vesicoureteral reflux (VUR) was
disclosed by VCUGin 14/51(27,4%, 8
group A, 6 group B) cases
PCT cut off:
>0.5ng/ml NPV
>0.85ng/ml NPPV
>1.2ng/ml PPV
RESULTS

17. DMSA is required in patients
with high PCT levels and
negative US examined
CONCLUSIONS
The combination of high PCT
levels and positive US findings
is an indication of upper UTI

18. CONCLUSIONS
Normal US and PCT levels
can exclude upper UTI
…and thus protect small patient from unnecessary DMSA