A prospective study of patients with radiological pyelonephritis, papillary necrosis and obstructive atrophy

Abstract

Twenty-six patients with radiological unilateral chronic pyelonephritis, 36 patients with bilateral chronic pyelonephritis, 14 patients with papillary necrosis and nine patients with obstructive atrophy have been followed from five to 135 months for a total of 374 patient years. Serial changes in renal function and pyelographic appearances have been correlated with bacteriuria, analgesic ingestion, blood pressure and reflux. The calculated survival rate at five years was 95 per cent for patients with bilateral pyelonephritis and 92 per cent for patients with papillary necrosis. The ten-year survival rate was 86 per cent and 56 per cent respectively. The survival rate for patients with unilateral pyelonephritis and obstructive atrophy was 100 per cent at five and ten years. Bacteriuria was not associated with deteriorating renal function determined by serial plasma creatinine estimations. Although all patients in whom there was some radiographic change had bacteriuria on later review, other factors, including excess analgesic intake, reflux and stones were recognized in most. There was a high incidence of analgesic ingestion among patients whose renal function declined and in whom there was some change in serial radiographs. The prevalence of hypertension among patients with normal renal function was 12 and 28 per cent for patients with unilateral pyelonephritis and bilateral pyelonephritis respectively. There was a significant increase in both blood urea and plasma creatinine in all patients with hypertension (diastolic pressure greater than 90 mm Hg) and a much higher prevalence of hypertension in patients whose plasma creatinine exceeded 1.3 mg/100 ml. Thrity per cent of patients with unilateral pyelonephritis and 50 per cent with bilateral pyelonephritis had vesicoureteric reflux of varying degrees. There was no evidence to suggest that major degrees of reflux (grade 3) was associated with further renal damage. These observations indicate the benign course of the majority of patients with radiological pyelonephritis. Control of blood pressure, and analgesic intake will help to preserve renal function whilst prevention of symptomatic urinary infection by long term low dose therapy will reduce morbidity.