RESUMO
BACKGROUND: Acute renal failure (ARF) due to acute pyelonephritis (APN) in patients in the absence of obstructive uropathy, diabetes, or chronic renal failure was reported rarely (12 cases in the last 25 yrs in Clin Inf Dis, 1992; 243-6 by SR Jones)2). Acute renal failure is a rare complication of acute pyelonephritis in patients who do not have urinary obstruction. Although urinary tract infections are common in adults, pyelonephritis is rarely considered in the differential diagnosis of acute renal failure, and when clinicians weigh the possible consequences of bacteriuria, renal failure is not considered to be a reasonable possibility. METHODS: We observed 6 patients of acute pyelonephritis associated with acute renal failure as an initial manifestation on admission in the past 6 months. The analysis of clinical features of these 6 patients (APN+) compared to 7 patients of APN without ARF (APN-) revealed following data. RESULTS: All were female in both groups. The mean age was 331.7 years in APN+ and 48+6 years in APN-, respectively (p, ns). All in both APN- and APN+ were caused by E. coli. But, none in both groups except 1 in APN- had bacteremia. The previous history of UTI was present in 5 in APN-, but none in APN+. Duration of clinical symptoms before admission (8.4+/-0.5 vs. 4.4+/-1.0 days, P<0.05) and admission days (24.2+/-1.8 vs. 11.1+/-1.5 days, p=0.000) were significantly longer in APN+. On admission, HUN and serum creatinine was 45+/-2.7mg/dL and 3.5+/-0.2mg/dL in APN+, respectively. No one in APN+ required dialysis, and subsequently recovered renal function with prompt antibiotic therapy resulting in no significant difference compared to that of APN on discharge (serum creatinine, 1.0+/-0.1 vs. 0.9+/-0.1mg/dL). No differences in leukocytosis and serum electrolyte levels on admission were present. However, significant anemia was noted in APN+ (hemoglobin, 9.0+/-0.7 vs. 11.9+/-0.2gm/dL). The days of fever and leukocytosis before disappearance were not different in both groups, but those of flank pain (12.8+/-1.5 vs. 5.7+/-0.7 days, P=0.001) and pyuria (16+/-1.9 vs. 6.4+/-0.6 days, P=0.000) significantly longer in APN+. Upon ultrasonography, all in APN+ showed enhanced echogenicity, but I in APN . (P=P value, NS=not significant) CONCLUSION: Upon these data, we concluded that ARF associated with APN as an initial manifestation was accompanied by several distinct clinical characteristics, which could be used for the early recognition of its unusual occurrence and subsequent appropriate management including antibiotics leading to a favorable outcome.