부산대학교 도서관

Background: Though a diagnosis of urinary tract infection (UTI) should be made by the confirmation of significant bacteriuria, the presence of pyuria which can be examined by microscopic analysis using urine sediment leads us to have a high index of suspicion for UTI in children. Recently, we encountered several children with upper UTI having no pyuria.Aims: To characterize the children with upper UTI having no pyuria.Subjects and Methods: Retrospective analysis using medical record was performed in 129 children (male/female 88/41, median age 4.12 mo.) with upper UTI admitted to our hospital during 2004 and 2008. These children were classified into 2 groups according to the presence of pyuria: group A, children with upper UTI having pyuria, group B, children with upper UTI having no pyuria. Significant pyuria was defined as more than 4 leukocytes in the urine sediment per high power field under light microscopy. Age (mo.), sex ratio (male/female), time from the onset of pyrexia to urine sampling (hours), maximum body temperature (°C), maximum white blood cell count (WBC) in the peripheral blood (per mL), maximum serum level of c- reactive protein (CRP, mg/dL) during the course of illness were compared between groups. Furthermore, the prevalence of vesicoureteral reflux (VUR) in both groups was also analyzed.Results: Among 129 children with upper UTI, 111 had significant pyuria (86%, group A) while 18 children did not (14%, group B). There were no significant differences between group A and group B in age, sex ratio, time from the onset of pyrexia to urine sampling, maximum body temperature, maximum WBC count, maximum serum level of CRP and the prevalence of VUR. Interestingly enough, there was a difference in the most frequently detected causative pathogen between group A and group B: E. coli was detected in 90 out of 111 (81%) in group A, whereas Enterococcus was detected in 7 out of 18 (39%) in group B.Conclusion: In children with upper UTI, absence of pyuria is not rare finding, particularly in children with UTI caused by Enterococcus spp. The presence of significant bacteriuria, therefore, should be sought in suspected cases.