Resistive Index (RI) in Febrile Urinary Tract Infection: Predictive Value of Renal Outcome

Urinary tract infection is the most common bacterial infection in pediatric.

The Ultrasonography of bladder and kidneys – is a relatively cheap, non-invasive and fast test that enables to find children with anatomical anomalies. Also this test does not pose risk of radiation exposure.

Voiding cystourethrogram – is the test of choice to establish the presence of vesicoureteral reflux, that is a major risk factor for future infections and scaring. This test have a radiation exposure risk, it is invasive and relatively complex to preform .

DMSA scintigraphy test – may be performed to determine acute pyelonephritis or to investigate kidney scarring. This test have greater radiation exposure risk. But it cannot distinguish between dysplasia of a kidney or a scarring .

With the development and improvement of the imaging capabilities of Doppler ultrasonography we can measure the Resistive Index, which is a sonographic value to assess the kidney function.

In this work we want to measure if the Resistive Index can predict kidney scarring.

We followed after 71 cases of kids from 0 to 11 years old that was admitted to our hospital – Puria, in the diagnosis of Urinary tract infection.

The diagnosis was made on the base of clinical presentation, laboratory blood analysis, urinary analysis and urinary cultures.

We measured the Resistive index in all of these patients. And they did the ordinary US of kidney parenchyma, the DMSA study and a cystography by the accepted protocols of our department.

In conclusion we found : In the first group under 2 years old we found e medium correlation between the RI and DMSA study. And there was a strong correlation between RI and cystography. In the second group above 4 years we found a strong correlation between RI both to DMSA and cystography.