Epidemiology of severe purulent pyelonephritis: narrative review
DOI: 10.32364/2587-6821-2026-10-4-9
Epidemiology of severe purulent pyelonephritis: narrative review
V.N. Pavlov1, V.A. Vorobyov1,2, V.A. Ananiev1,3
1 Bashkir State Medical University, Ufa, Russian Federation
2 Irkutsk State Medical University, Irkutsk, Russian Federation
3 Territory Regional Clinical Hospital, Barnaul, Russian Federation
Severe purulent pyelonephritis (SPP) does not have a single international definition, and foreign authors is more often consider it as a part of severe phenotypes of acute pyelonephritis, complicated urinary tract infections, renal abscesses, emphysematous pyelonephritis and urosepsis.
Аim: to summarize current data on epidemiology of SPP and related severe phenotypes of complicated pyelonephritis; to identify key demographic and clinical features, risk factors, pathogenetic mechanisms, microbiological trends, outcomes, and directions for further studies.
The review analyzes clinical guidelines, population-based studies, systematic reviews, and meta-analyses. According to Global Burden of Disease studies, more than 404.6 million cases of urinary tract infections and related fatal outcomes were reported (236.8 thousand and 5.2 million years of healthy life lost adjusted for disability) in 2019; in 2021, standardized morbidity was 5531.88 per 100000. Population-based studies of acute pyelonephritis demonstrate marked heterogeneity: from 4.2 cases per 10000 person years (according to the Spanish Primary Care Network) to 39.1 cases per 10000 (Korea).
Given this epidemiological heterogeneity, identification of risk groups is of practical importance. Elderly age, pregnancy, diabetes mellitus, obesity, urinary tract obstruction, urolithiasis, catheterization, immunosuppression, and antibiotic-resistant pathogens are main risk factors for severe course. For example, emphysematous pyelonephritis is accompanied by high mortality, and catheterization is associated with a daily increase in bacteriuria by 3-8%. The review highlights a need for local SPP registries and adaptation of treatment algorithms to regional resistance data.
Keywords: severe purulent pyelonephritis, acute pyelonephritis, complicated urinary tract infections, urosepsis, kidney abscess, emphysematous pyelonephritis, antibiotic resistance.
For citation: Pavlov V.N., Vorobyov V.A., Ananiev V.A. Epidemiology of severe purulent pyelonephritis: narrative review. Russian Medical Inquiry. 2026;10(4):227–234 (in Russ.). DOI: 10.32364/2587-6821-2026-10-4-9
About the authors:
Valentin N. Pavlov — Academician of the Russian Academy of Sciences, Dr. Sc. (Med.), Professor, Rector of BashkirState Medical University; 3, Lenin str., Ufa, 450008, Russian Federation; ORCID iD 0000-0003-2125-4897
Vladimir A. Vorobyov — Dr. Sc. (Med.), Assistant Professor of the Department of Urology and Oncology, Bashkir State Medical University; 3, Lenin str., Ufa, 450008, Russian Federation; Professor of the Department of Faculty Surgery and Urology, Irkutsk State Medical University; 1, Krasnogo Vosstaniya str., Irkutsk, 664003, Russian Federation; ORCID iD 0000-0003-3285-5559
Vladimir A. Ananiev — C. Sc. (Med.), Postdoctoral Student of the Department of Urology and Oncology, Bashkir State Medical University; 3, Lenin str., Ufa, 450008, Russian Federation; Head of the Department of Urology No. 2, Territory Regional Clinical Hospital; 1, Lyapidevsky str., Barnaul, 656045, Russian Federation; ORCID iD 0000-0002-1636-3151
Contact information: Vladimir A. Ananiev, e-mail: urologkkb@mail.ru
Financial Disclosure: no authors have a financial or property interest in any material or method mentioned.
There is no conflict of interest.
Received 15.03.2025.
Revised 07.04.2025.
Accepted 30.04.2025.
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