Scarring following renal trauma in children

To assess factors relating to renal scarring following kidney injury.

A total of 25 children who had documented renal injury between 1981 and 1988 were included in the study and 19 were followed up for 1 month to 12 years (mean 5.5 years) and the development of hypertension and renal scars assessed using ultrasonography and radionuclide scans (dimercapto-succinic acid, DMSA).

Of the 19 children 13 had renal contusions, four had renal lacerations and two sustained severe renal injury, one of whom had pelvi-ureteric disruption. Eighteen patients presented with macroscopic or microscopic haematuria except the patient with pelvi-ureteric junction disruption who presented 3 weeks later with abdominal distension, vomiting and hypertension. All the patients were managed without an operation except the latter patient who required nephrectomy. Renal scarring was demonstrated in four children at a mean follow-up of 3.5 years, one following renal contusion (5% scarring), two after renal laceration (50% scarring) and one after rupture of the kidney (100% scarring). In one patient intravenous pyelography did not reveal a renal scar but a radionuclide scan performed 5 years later demonstrated a scar. Transient hypertension was noted in only two patients but peripheral plasma renin levels were normal.

Renal scars developed in four of 19 patients with renal trauma and more than half of the patients with severe renal injury. Long-term follow-up including a radionuclide scan is therefore necessary in patients with renal injury. Although no sustained hypertension was noted in any patients in this study, long-term blood pressure assessments would seem prudent.