The natural history of chronic pyelonephritis in the adult.

One hundred and thirty patients with primary chronic pyelonephritis diagnosed radiologically or by nephrectomy, 84 with unilateral and 46 with bilateral disease, have been followed for six to 240 months. The clinical and radiological features of the disease at presentation, together with its influence on pregnancy, have been analysed. Serial observations of bacteriuria, blood pressure and renal function have been made during follow up and the intravenous urogram (IVU) has been repeated after five years in most patients. Although the disease probably starts in early childhood it often presents to the nephrologist in young adults, mainly women, as symptomatic urinary tract infection, hypertension, renal insufficiency or a combination of these features. Though associated with increased morbidity in pregnancy it does not usually interfere with fertility and in this series it did not cause increased fetal loss. Repeated urinary tract infections and hypertension are common events. Proteinuria is usually minimal and when present is associated with hypertension. The disease in most patients with unilateral disease runs a benign course; a poorer prognosis is associated with bilateral disease, hypertension and proteinuria. Since we found no association between frequent urinary infections and declining renal function we suggest that only symptomatic urinary infection should be treated in adults with chronic pyelonephritis.