Vol.74 No.3 May 2026

Usefulness of blood culture in patients with bloodstream infections derived from urinary tract

Hideaki Ayukawa^{1, 2)}, Tetsuya Horino³⁾, Shin-ichi Takahashi^{1, 2)}, Yuki Arai^{1, 2)}, Kazumi Sakamoto²⁾, Taira Nakamura²⁾, Mitsutaka Sasaki²⁾, Mayuko Matsuzawa²⁾, Tokio Hoshina³⁾ and Koji Yoshikawa^{2, 3)}

¹⁾Department of Laboratory Medicine, The Jikei University Katsushika Medical Center
²⁾Department of Infection Control, The Jikei University Katsushika Medical Center
³⁾Division of Infectious Diseases, Department of Internal Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-Ku, Tokyo, Japan

Abstract

Despite the high frequency of development of bloodstream infection in patients with urinary tract infections, several reports have suggested reevaluation of the need for blood cultures in these patients because of the high concordance rate between the results of blood and quantitative urine cultures. Therefore, in this retrospective study, we investigated the concordance rate between the results of blood culture and quantitative urine culture in adult cases with bacteremia secondary to urinary tract infection at The Jikei University Katsushika Medical Center between May 2022 and April 2024. During the 2-year study period, a total of 107 patients met the inclusion criteria. The median age of the patients was 79 years, and 52 patients (48.6%) were male. The most common underlying disease was solid tumors (n=44; 41.1%), including 31 cases of urinary tract cancer, followed by diabetes mellitus (n=28; 26.2%). Of the 107 patients, 22 (20.6%) had catheter-associated urinary tract infections. Escherichia coli was the most commonly isolated bacterial species from the blood cultures (61 cases; 57.0%), followed by Klebsiella pneumoniae (12 cases; 11.2%). In addition, antimicrobial agents were changed in 66 of the 107 cases (61.7%) after the results of blood culture/quantitative urine culture became known. The concordance rate between the results of blood culture and quantitative urine culture was 48.6% (52 cases), and multivariate analysis showed that anatomic abnormalities of the urinary tract were significantly more common in the discordant results group (p=0.006). The concordance rate between the results of blood and quantitative urine cultures in this study was lower than that reported previously, especially in cases with anatomic abnormalities of the urinary tract. The results suggest that blood culture would be useful in cases of urinary tract infection with anatomic abnormalities of the urinary tract, and patients with urinary catheters, in addition to cases who are post-prostate biopsy and/or receiving antibiotic therapy.

Key word

blood culture, urine culture, bloodstream infection, urinary tract infection

Received

July 18, 2025

Accepted

December 24, 2025

Jpn. J. Chemother. 74 (3): 412-420, 2026