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Introduction to Urinary Tract Infections (UTIs)

By

Talha H. Imam

, MD, University of Riverside School of Medicine

Reviewed/Revised Jan 2024
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Urinary tract infections (UTIs) can be divided into upper and lower tract infections:

However, in practice, and particularly in children, differentiating between the sites of infection may be difficult or impossible. Moreover, infection often spreads from one area to the other. Although urethritis and prostatitis are infections that involve the urinary tract, the term UTI usually refers to pyelonephritis and cystitis.

Bacterial urinary tract infections Bacterial Urinary Tract Infections Bacterial urinary tract infections (UTIs) can involve the urethra, prostate, bladder, or kidneys. Symptoms may be absent or include urinary frequency, urgency, dysuria, lower abdominal pain... read more cause most cases of cystitis and pyelonephritis. The most common nonbacterial pathogens are fungi Fungal Urinary Tract Infections Fungal infections of the urinary tract primarily affect the bladder and kidneys. (See also Introduction to Urinary Tract Infections [UTIs].) Species of Candida, the most common cause... read more (usually candidal species) and, less commonly, mycobacteria, viruses, and parasites. Nonbacterial pathogens usually affect patients who are immunocompromised; have diabetes, obstruction, or structural urinary tract abnormalities; or have had recent urinary tract instrumentation.

Other than adenoviruses (implicated in hemorrhagic cystitis), viruses have no major contribution to UTI in immunocompetent patients.

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NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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