Pediatric uroradiology

The intravenous urogram in the detection and evaluation of renal damage following urinary tract infection

Intravenous urography (IVU) still provides the most comprehensive structural assessment of the urinary tract. In particular, the radiological renal appearances approximate closely to the morphology of the renal scarring of reflux nephropathy or chronic atrophic pyelonephritis. It also provides reproducible renal measurements for follow-up assessment of renal growth and scarring. It is now less often used for first-line investigation of the acute urinary tract infection (UTI) because the swelling accompanying acute renal involvement is less easily recognised than the areas of defective function demonstrated on 99mtechnetium-dimercaptosuccinic acid (DMSA) studies. Also IVU contributes a higher radiation dose when calculated for full IVU (dependent on the number of films exposed) and there is a slight risk of side effects from injected contrast media, reduced by using non-ionic compounds. Because of its value in confirming such a serious diagnosis as renal scarring, suspected on ultrasonography or DMSA scintigraphy, modification of the technique of IVU with adequate preparation and the use of a reduced number of films, or single films localised to the renal areas, should be considered. Expertise in the interpretation of IVU must also be maintained because of the ancillary information regarding bowel and bladder function, the spine and evidence of stones, pertinent to the management of children with UTI and renal scarring. IVU and DMSA study remain complementary investigations.

Pitfalls in pediatric urinary sonography

Our review of pediatric urinary tract ultrasonograms over a period of two and one-half years resulted in a catalog of pitfalls. Cases included normal scans mistaken for abnormal and vice versa. These erroneous diagnoses stemmed from the inappropriate selection of the primary imaging test, improper timing of the ultrasonogram, errors of commission or omission in performance of the scans, and improper interpretation of the findings. For ease of reference, the pitfalls are grouped under bladder, ureters, and kidney with emphasis on the first two which are common sources of error.

Urinary tract infections in infants and children. Guidelines for averting permanent damage

Urinary tract infection (UTI) is common in childhood and, early in life, is often associated with vesicoureteral reflux or other urinary tract anomalies. Since the combination of reflux and infection can cause renal scarring and impaired renal function, identification of children at risk and provision of close follow-up are important. Diagnosis in the first year of life relies on a high index of suspicion on the part of the clinician, as signs and symptoms are nonspecific. Reliable cultures are the cornerstone of accurate diagnosis and will be the basis for selection of acute and long-term management. Vigilant follow-up of all children with UTI can prevent ultimate morbidity.