ABSTRACT
PURPOSE: Acute pyelonephritis (APN) is mostly caused by ascending infection. Based on clinical and experimental studies, it is known that APN is caused by bacteria that ascends from the bladder through the ureter to the renal pelvis and parenchyma. Urinary reflux, bacterial virulence factors, and decreased ureteral peristalsis are some of the causes of ascending infection. We have tried to evaluate the significance of reflux in adult uncomplicated APN. MATERIALS AND METHODS: Voiding cystourethrogram (VCUG) was performed in 71 female patients with APN who showed no structural abnormalities on either intravenous urogram or ultrasonogram from April 1998 to May 2000. VCUG was performed at cure phase (29.7+/-9.18 days, 20 patients) in the early days of the study and the date of performing VCUG was shortened gradually to resolved phase (13.8+/-2.13 days, 10 patients), subacute phase (6.60+/-1.84 days, 10 patients), and acute phase (2.42+/-0.51 days, 31 patients). RESULTS: There were only 2 (2.8%) cases with vesicoureteral reflux among 71 female patients with uncomplicated APN. 1 ipsilateral grade 2 reflux was found among the 20 patients who underwent VCUG at cure phase. 1 case with ipsilateral grade 1 reflux was found at resolved phase. Reflux was not found in the groups where study was performed at subacute and acute phase. The cause of infection was found to be E. coli (55 patients, 77.5%), Enterococcus faecalis (3 patients, 4.2%), Klebsiella pneumoniae (2 patients, 2.8%), and S. aureus (1 patients, 1.4%). CONCLUSIONS: These results suggest that reflux may not be a significant factor causing ascending infection that leads to APN. More study on the pathophysiology of ascending infection to the upper urinary tract is warranted.