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Last reviewed: 16 Mar 2025
Last updated: 24 Jan 2024

Summary

Definition

History and exam

Key diagnostic factors

  • dysuria
  • new nocturia
  • cloudy-looking urine
  • risk factors
  • fever

Other diagnostic factors

  • urgency
  • visible haematuria
  • frequency
  • suprapubic pain or tenderness
  • flank pain
  • costo-vertebral angle tenderness
  • new incontinence
  • new or worsening delirium/debility
  • loss of diabetic control
  • malaise
  • rigors

Risk factors

  • sexual activity
  • spermicide use
  • post-menopause
  • positive family history of UTIs
  • history of recurrent UTI
  • presence of a foreign body
  • insulin-treated diabetes
  • high lifetime number of UTIs
  • recent antibiotics
  • poor bladder emptying
  • increasing age

Diagnostic investigations

1st investigations to order

  • urine dipstick
  • urine culture and sensitivity

Investigations to consider

  • urine microscopy
  • post-void residual
  • renal ultrasound
  • abdominal/pelvic CT

Treatment algorithm

Contributors

Expert advisers

Andrew Lewington, BSc (Hons), MBBS, MEd, MD, FRCP

Consultant Renal Physician

Honorary Associate Professor

Nephrology Department

Leeds Teaching Hospitals NHS Trust

Head of MBChB

School of Medicine

University of Leeds

Leeds

UK

Disclosures

AL has been the principal applicant/co-applicant for a number of grants including: Engineering and Physical Sciences Research Council Research - Multiplexed AKI biomarker detection with a single molecule biosensor; Leeds Cares - A novel, non-invasive diagnostic approach to assess kidney transplant health through the targeted measurement of biomarkers of kidney injury and immune response in kidney transplant recipients at the Leeds Teaching Hospitals NHS Trust; Kidney Research Yorkshire - Use of enhanced technology to characterise haemodialysis treatment for acute kidney injury (AKI); Bringing It Home - Validation of a micro-sampling technique for measuring tacrolimus and creatinine remotely; and to fund a research nurse; British Renal Society - Renal function assessment with point of care creatinine in diverse populations (RAPID), and several NIHR grants including on a) Improving the quality of post-discharge care following AKI b) An investigation into the use of remote blood sample collection to reduce health inequalities in patients with mental health disorders c) A comparison of remote blood collection devices: a human factor use study d) Defining the characteristics for a novel automatic device to monitor urine output in catheterized patients e) Leeds Medtech and In-vitro Diagnostic Cooperative Grant Extension f) Surgical MedTech Co-operative for the 2019/20 proof-of-principle funding stream g) A pilot investigation into the use of beta-trace protein for residual renal function estimation in haemodialysis h) Application of functional MRI to improve assessment of chronic kidney disease (AFiRM study) i) SuperResPath-Renal: Quantitative super-resolution technology for a fast, decentralised clinical diagnosis of renal pathologies. AL is the co-author of a number of manuscripts including on extracorporeal treatments, AKI, kidney function testing prior to contrast-enhanced CT, plasma exchange and glucocorticoids in severe ANCA-associated vasculitis, COVID-19 rapid diagnostics, multimodal image-guided ablation on management of renal cancer in Von-Hippel-Lindau syndrome, and on a summary of NICE guidance on CKD. AL is the author of several book chapters on nephrology and AKI. AL has received expenses for accommodation and travel for conferences at which he has given lectures, other than those delivered virtually. AL was a member of the AKI Scientific Program Committee for the ISN World Congress of Nephrology 2020-2021 and Chair of this same committee in 2021-2022.

Acknowledgements

BMJ Best Practice would like to gratefully acknowledge the previous expert contributors, whose work has been retained in parts of the content:

Una J. Lee, MD

Female Pelvic Medicine and Reconstructive Surgery Section of Urology and Renal Transplantation

Virginia Mason Medical Center

Seattle

WA

Disclosures

UJL declares that she has no competing interests.

Peer reviewers

Sheilagh Reid

Consultant Urological Surgeon

Princess Royal Spinal Injuries Unit

Sheffield Teaching Hospitals NHS Foundation Trust

Sheffield

UK

Disclosures

SR is lead for the spinal injuries urology course; in the past this course has received funding from Coloplast, AMS, and Hollister. SR is chair of the Female, Neurological, and Urodynamic Urology section of the British Association of Urological Surgeons.

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