Correlation of CT-Derived Quantitative Image Features and Inflammatory Laboratory Markers with Length of Hospital Stay in Patients with Pyelonephritis

Graf, Markus; Lemke, Tristan; Marka, Alexander W.; Lenhart, Nicolas; Ziegelmayer, Sebastian; Makowski, Marcus R.; Reischl, Stefan; Sauter, Andreas; Bressem, Keno K.; Adams, Lisa C.; Huber, Thomas

doi:10.3390/diagnostics16183044

This is an early access version, the complete PDF, HTML, and XML versions will be available soon.

Open AccessArticle

Correlation of CT-Derived Quantitative Image Features and Inflammatory Laboratory Markers with Length of Hospital Stay in Patients with Pyelonephritis

by

Markus Graf

^†,

Tristan Lemke

^*,†,

Alexander W. Marka

,

Nicolas Lenhart

,

Sebastian Ziegelmayer

,

Marcus R. Makowski

,

Stefan Reischl

,

Andreas Sauter

,

Keno K. Bressem

,

Lisa C. Adams

and

Thomas Huber

Department of Diagnostic and Interventional Radiology, Klinikum Rechts der Isar, School of Medicine and Health, Technical University of Munich, 81675 Munich, Germany

^*

Author to whom correspondence should be addressed.

^†

These authors contributed equally to this work.

Diagnostics 2026, 16(18), 3044; https://doi.org/10.3390/diagnostics16183044 (registering DOI)

Submission received: 7 July 2026 / Revised: 12 September 2026 / Accepted: 15 September 2026 / Published: 19 September 2026

(This article belongs to the Section Medical Imaging and Theranostics)

Download Versions Notes

Abstract

Background/Objectives: To assess associations between quantitative computed tomography (CT) features, inflammatory markers, and length of hospital stay (LOS) in acute pyelonephritis (APN). Methods: This retrospective single-center study included 82 patients with CT-confirmed APN. Two radiologists quantified renal perfusion-deficit volume and percentage and perirenal fat-stranding (PFS) area and attenuation. Associations with C-reactive protein (CRP), white blood cell (WBC) count, procalcitonin, and LOS were assessed using Spearman correlation and regression analyses. Receiver operating characteristic (ROC) curve analysis evaluated LOS ≥ 10 days. Results: Perfusion-deficit volume and percentage correlated strongly with CRP (ρ = 0.763 and 0.714; both p < 0.001) and weakly with WBC count (ρ = 0.379 and 0.374; both p < 0.001). PFS area correlated moderately with procalcitonin (ρ = 0.482, p = 0.001; n = 42). Both perfusion-deficit measures correlated moderately with LOS (ρ = 0.538 and 0.536; both p < 0.001). In adjusted linear regression, CRP remained associated with LOS (Coefficient = 0.523 days per 10 mg/L; 95% CI, 0.345–0.692; p < 0.001), whereas perfusion-deficit percentage did not (p = 0.430). In adjusted logistic regression, CRP, age, and male sex were associated with LOS ≥ 10 days. The multivariable model yielded an AUC of 0.883 (95% CI, 0.81–0.95). Results were unchanged in a sensitivity analysis excluding the seven outpatients, and bootstrap internal validation yielded an optimism-corrected AUC of 0.86. Conclusions: Quantitative renal perfusion deficits were associated with inflammatory burden and LOS in univariable analyses. CRP showed the most consistent independent association, whereas the incremental value of CT metrics requires external validation.

Keywords: acute pyelonephritis; APN; CT; quantitative imaging features; length of hospital stay; LOS

Share and Cite

MDPI and ACS Style

Graf, M.; Lemke, T.; Marka, A.W.; Lenhart, N.; Ziegelmayer, S.; Makowski, M.R.; Reischl, S.; Sauter, A.; Bressem, K.K.; Adams, L.C.; et al. Correlation of CT-Derived Quantitative Image Features and Inflammatory Laboratory Markers with Length of Hospital Stay in Patients with Pyelonephritis. Diagnostics 2026, 16, 3044. https://doi.org/10.3390/diagnostics16183044

AMA Style

Graf M, Lemke T, Marka AW, Lenhart N, Ziegelmayer S, Makowski MR, Reischl S, Sauter A, Bressem KK, Adams LC, et al. Correlation of CT-Derived Quantitative Image Features and Inflammatory Laboratory Markers with Length of Hospital Stay in Patients with Pyelonephritis. Diagnostics. 2026; 16(18):3044. https://doi.org/10.3390/diagnostics16183044

Chicago/Turabian Style

Graf, Markus, Tristan Lemke, Alexander W. Marka, Nicolas Lenhart, Sebastian Ziegelmayer, Marcus R. Makowski, Stefan Reischl, Andreas Sauter, Keno K. Bressem, Lisa C. Adams, and et al. 2026. "Correlation of CT-Derived Quantitative Image Features and Inflammatory Laboratory Markers with Length of Hospital Stay in Patients with Pyelonephritis" Diagnostics 16, no. 18: 3044. https://doi.org/10.3390/diagnostics16183044

APA Style

Graf, M., Lemke, T., Marka, A. W., Lenhart, N., Ziegelmayer, S., Makowski, M. R., Reischl, S., Sauter, A., Bressem, K. K., Adams, L. C., & Huber, T. (2026). Correlation of CT-Derived Quantitative Image Features and Inflammatory Laboratory Markers with Length of Hospital Stay in Patients with Pyelonephritis. Diagnostics, 16(18), 3044. https://doi.org/10.3390/diagnostics16183044

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Menu

Correlation of CT-Derived Quantitative Image Features and Inflammatory Laboratory Markers with Length of Hospital Stay in Patients with Pyelonephritis

Abstract

Share and Cite

Article Metrics

Article Access Statistics

Further Information

Guidelines

MDPI Initiatives

Follow MDPI