Back to Journals » International Journal of General Medicine » Volume 10

Perirenal fat stranding is not a powerful diagnostic tool for acute pyelonephritis

Authors Fukami H, Takeuchi Y, Kagaya S, Ojima Y, Saito A, Sato H, Matsuda K, Nagasawa T

Received 2 February 2017

Accepted for publication 29 March 2017

Published 8 May 2017 Volume 2017:10 Pages 137—144

DOI https://doi.org/10.2147/IJGM.S133685

Checked for plagiarism Yes

Review by Single-blind

Peer reviewers approved by Dr Amy Norman

Peer reviewer comments 2

Editor who approved publication: Dr Scott Fraser


Hirotaka Fukami, Yoichi Takeuchi, Saeko Kagaya, Yoshie Ojima, Ayako Saito, Hiroyuki Sato, Ken Matsuda, Tasuku Nagasawa

Department of Nephrology, Japanese Red Cross Ishinomaki Hospital, Ishinomaki, Miyagi Prefecture, Japan

Purpose: Pyelonephritis, an upper urinary tract infection, is a serious infection that often requires hospitalization. However, the accurate diagnosis of acute pyelonephritis can be difficult, especially among older individuals who can present with unusual symptoms. Imaging with computed tomography (CT) is not unusual in the diagnosis of pyelonephritis, with some clinicians regarding perirenal fat stranding (PFS) as a characteristic finding. However, the sensitivity and specificity of PFS in diagnosing pyelonephritis are currently unknown. We therefore sought to clarify the relevance of PFS in diagnosing acute pyelonephritis.
Patients and methods: We conducted a case-controlled retrospective analysis of medical records. The pyelonephritis group included 89 patients who had been diagnosed with acute pyelonephritis, while the control group included 319 patients who had undergone percutaneous renal biopsy. CT findings were available for both groups. The frequency of PFS and its sensitivity and specificity for the diagnosis of acute pyelonephritis were investigated.
Results: The mean ages of the pyelonephritis and control groups were 74±15 years and 63±16 years, respectively. A total of 28% of men were in the pyelonephritis group vs 61% of men in the control group. The frequency of PFS was 72% in the pyelonephritis group vs 39% in the control group. Age and renal dysfunction were associated with an increased frequency of PFS. After adjusting for age, sex, and renal function using a propensity score analysis, the sensitivity, specificity, and positive likelihood ratio of PFS for diagnosing acute pyelonephritis were 72%, 58%, and 1.7, respectively.
Conclusion: The presence of PFS was not useful in diagnosing acute pyelonephritis.

Keywords: acute pyelonephritis, perirenal fat stranding, sensitivity, specificity, urinary tract infection, CT

Corrigendum for this paper has been published
 

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]