Which test for schistosomiasis?
Q How likely are further investigations to be positive in a child with UTI?
A Ultrasound as a first-line allows structural abnormality to be seen. The gold standard for reflux is a micturating cysto-urethrogram and for renal problems is a DMSA scan. In a study of 255 children under five with a first diagnosed uncomplicated febrile urinary infection, renal ultrasound detected abnormality in 14.1 per cent but it did not influence management.
Micturating cysto-urethrogram revealed reflux in 18.4 per cent of patients of grade I to III and this recognised the lower sensitivity of ultrasound for reflux. It was suggested that repeat ultrasound should be limited to those who had complicated cause and micturating cysto-urethrogram should be used as the sole screening test.
Clear gender-specific differences in renal scarring have been established with global persistent loss more common in boys with dilated vesico ureteric reflux, and focal scarring in the absence of vesico ureteric reflux more common in girls, particularly after recurrent febrile UTIs.
These findings support the contention that high-grade reflux (grade IV and V) is associated with renal dysplasia that occurs during fetal life as a risk factor for postnatal renal decline. The initial imaging guidelines for febrile children up to the age of two involve a combination of ultrasound, contrast cystography or isotope cystography plus renal cortical scintigraphy with technetium 99m Di Mercapto Succinic Acid (DMSA).
A bladder ultrasound is very useful in demonstrating bladder wall thickening and large residual volumes after bladder emptying in the child with UTI and day-wetting.
Mr Amir Azmy ,consultant paediatric urologist, Royal Hospital for Sick Children, Glasgow