This document discusses urinary tract infections (UTIs). It begins by defining UTIs as infections of either the upper urinary tract (kidneys/pyelonephritis) or lower urinary tract (bladder/cystitis, urethra/urethritis, prostate/prostatitis). It then covers the epidemiology of UTIs, noting they are much more common in women ages 20-50 compared to men of the same age. The document categorizes UTIs as uncomplicated or complicated and discusses recurrent UTIs. It identifies the most common bacterial causes of UTIs as Escherichia coli and other gram-negative and gram-positive bacteria. Risk factors for UTIs in women include sexual

1. PATHOPHYSIOLOGY
URINARY TRACT
INFECTIONS
Nem Kumar Jain
MS (Pharm.) Pharmacology & Toxicology
Assistant Professor, School of Pharmacy
ITM University Gwalior

2. INTRODUCTION
• Urinary tract infections (UTIs) can be divided into
• Upper tract infections, which involve the kidneys (Pyelonephritis),
• Lower tract infections, which involve the bladder (Cystitis), urethra (Urethritis), and
prostate (Prostatitis).
• Although urethritis and prostatitis are infections that involve the urinary tract, the
term UTI usually refers to pyelonephritis and cystitis.
• Symptomatic presence of microbes and associated inflammation in urinary tract

3. EPIDEMIOLOGY
• Among adults aged 20 to 50 years, UTIs are about 50-fold more common in
women. In women in this age group, most UTIs are cystitis or pyelonephritis. In
men of the same age, most UTIs are urethritis or prostatitis.
• The incidence of UTI increases in patients > 50 years, but the female:male ratio
decreases because of the increasing frequency of prostate enlargement and
instrumentation in men.
TYPES
Uncomplicated UTIs: UTIs that occur in premenopausal adult women with no
structural or functional abnormality of the urinary tract and who are not pregnant and
have no significant comorbidity that could lead to more serious outcomes.
Complicated UTI: A UTI is considered complicated if the patient is a child, is
pregnant, or has any of the following:
A structural or functional urinary tract abnormality and obstruction of urine flow
A comorbidity that increases risk of acquiring infection or resistance to treatment, such
as poorly controlled diabetes, chronic kidney disease, or immunocompromise
Recent instrumentation or surgery of the urinary tract
Recurrent UTIs: >3 symptomatic UTIs within 12 months following clinical therapy

4. ETIOLOGY
• Most cystitis and pyelonephritis are caused by bacteria.
• The most common nonbacterial pathogens are fungi (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.
• Bacterial UTIs:
• Gram negative: Escherichia coli (75-95% of cases), enterobacteria,
typically Klebsiella or Proteus mirabilis, and occasionally Pseudomonas aeruginosa
• Gram positive: Staphylococcus saprophyticus, Enterococcus faecalis (group D
streptococci) and Streptococcus agalactiae
• In hospitalized patients, E. coli accounts for about 50% of cases. The gram-
negative species Klebsiella, Proteus, Enterobacter, Pseudomonas,
and Serratia account for about 40%, and the gram-positive bacterial cocci E.
faecalis, S. saprophyticus, and Staphylococcus aureus account for the remainder.
Why do women get UTIs more often
than men?
Shorter urethra, and opening closer to

5. RISK FACTORS
• Sexual intercourse
• Diaphragm and spermicide use
• Antibiotic use
• New sex partner within the past year
• History of UTIs in 1st-degree female
relatives
• History of recurrent UTIs
• First UTI at early age
• Ageing: urine retention, diabetes,
impaired immune system, catheterization
PATHOGENESIS
Ascending Infection: most common route, microbes colonize in periurethral and
perinial areas and ascends bladder to kidney
Hematogenoous spread: bacterimea (staphylococcus aureus) blood borne spread
to kidney
Lymphatogenous spread
Direct extension from other organs: prostatis

6. PATHOGENESIS

7. SIGN AND SYMPTOMS

8. PREVENTION IS BETTER THAN CURE