Urinary tract infections in infants under six months of age

Kang, Min Joo; Shin, Hye Kyung; Yim, Hyung Eun; Je, Bo-Kyung; Eun, So Hee; Choi, Byung Min; Park, Jong-Tae; Eun, Baik Lin; Yoo, Kee Hwan

Original Article

Korean Journal of Pediatrics 2006;49(3):278-286.
Published online March 15, 2006.

Urinary tract infections in infants under six months of age

Min Joo Kang¹, Hye Kyung Shin¹, Hyung Eun Yim¹, Bo-Kyung Je², So Hee Eun¹, Byung Min Choi¹, Jong-Tae Park³, Baik Lin Eun¹, Kee Hwan Yoo¹

¹Department of Pediatrics, College of Medicine, Korea University, Seoul, Korea
²Department of Radiology, College of Medicine, Korea University, Seoul, Korea
³Department of Occupational and Environmental Medicine, College of Medicine, Korea University, Seoul,

6개월 미만 영아의 요로 감염

강민주^¹^, 신혜경^¹^, 임형은^¹^, 제보경^²^, 은소희^¹^, 최병민^¹^, 박종태^³^, 은백린^¹^, 유기환^¹

^¹고려대학교 의과대학 소아과학교실
^²고려대학교 의과대학 영상의학교실
^³고려대학교 의과대학 산업의학교실

Correspondence:
Byung Min Choi, Email: cbmin@korea.ac.kr

Abstract

Purpose
: Although suprapubic bladder aspiration(SBA) is the most reliable technique for identifying bacteriuria in young infant, no report has been published about the clinical manifestations of urinary tract infection(UTI) diagnosed by aspirated urine in Korea. This study was performed to examine clinical manifestations and related factors of UTI confirmed by a positive urine culture obtained by SBA in young infants.
Methods
: We reviewed medical records of 159 infants younger than six months of age, who had been admitted for UTI to Korea University Ansan Hospital from January 2002 to June 2005.
Results
: The male:female ratio was 5.1 : 1. The most common pathogen in urine culture was Escherichia coli(92.5 percent). Most of the gram-negative pathogens had high sensitivity to amikacin, or third generation cephalosporins and had low sensitivity to ampicillin, trimethoprim-sulfamethoxazole, or gentamicin. Hydronephrosis and vesicoureteral reflux(VUR) were present in 32.7 percent and 27.7 percent respectively. Renal cortical defects observed on DMSA scans were detected in 37.1 percent. Prolonged fever duration and hospital day, high erythrocyte sedimentation rate(ESR) and C-reactive protein(CRP) levels, hydronephrosis and VUR were related to the renal cortical defects(P<0.05). Rates of UTI-associated bacteremia and aseptic meningitis were 8.3 percent and 6.6 percent.
Conclusion
: Early differential diagnosis is very important in infants younger than 6 months of age with UTI because the clinical findings are non-specific and UTI-associated bacteremia and aseptic meningitis are concomitantly found. Because prolonged fever and higher ESR and CRP levels are risk factors of the renal cortical defects, radiologic evaluations and nephrologic follow-up were needed in identifying the predisposing congenital abnormalities and chronic renal scarring.

Key Words: Urinary tract infections , Infant , Pyelonephritis , Bacteremia , Meningitis