Urinary Tract Infection (UTI)

A urinary tract infection (UTI) is a bacterial infection that occurs in any part of your urinary system, including the kidneys, ureters, bladder, and urethra. Most infections involve the lower urinary tract — the bladder (cystitis) and the urethra (urethritis). **Key Facts:** - **Most common cause:** E. coli bacteria (80-90% of cases) - **Most affected:** Women (due to shorter urethra) - **Types:** Lower UTI (bladder/urethra) vs Upper UTI (kidneys - more serious) - **Treatment:** Antibiotics are highly effective - **Prevention:** Good hygiene, hydration, and urination habits **Types of UTIs:** - **Cystitis (bladder infection):** Most common; causes frequent, painful urination - **Urethritis:** Infection of the urethra; burning with urination - **Pyelonephritis ([kidney infection](/condition/kidney-infection)):** Serious upper UTI requiring prompt treatment **Related Conditions:** - [Kidney infection](/condition/kidney-infection) — UTI that spreads to kidneys (more serious) - [Kidney stones](/condition/kidney-stones) — can increase UTI risk - [Yeast infection](/condition/yeast-infection) — different infection, sometimes confused with UTI - [Interstitial cystitis](/condition/interstitial-cystitis) — chronic bladder condition with similar symptoms - [Prostatitis](/condition/prostatitis) — in men, prostate infection can cause similar symptoms **Important:** Untreated UTIs can spread to the kidneys and become serious. Seek treatment promptly.

**How UTIs Develop:** **1. Bacterial Entry:** Bacteria (usually E. coli from the intestines) enter the urinary tract through the urethra. In women, the short distance between the urethra and anus makes this easier. **2. Bacterial Growth:** Once inside, bacteria attach to the bladder wall and multiply. The warm, moist environment is ideal for bacterial growth. **3. Immune Response:** Your body's immune response causes inflammation, leading to the burning, urgency, and discomfort of a UTI. **Why Women Get More UTIs:** - Shorter urethra (bacteria travel less distance to bladder) - Urethra closer to anus (easier bacterial spread) - Sexual activity can push bacteria into urethra - Hormonal changes ([menopause](/condition/menopause)) reduce protective bacteria **Risk Factors:** - Female anatomy - Sexual activity (especially with new partner) - Certain birth control methods (diaphragm, spermicides) - Menopause and low estrogen - Urinary tract abnormalities - Kidney stones or enlarged prostate - [Diabetes](/condition/type-2-diabetes) (impaired immune function) - Catheter use

**Uncomplicated UTI (Bladder Infection):** **First-Line Antibiotics:** - **Nitrofurantoin (Macrobid):** 100mg twice daily for 5 days - **Trimethoprim/sulfamethoxazole (Bactrim):** 1 DS tablet twice daily for 3 days - **Fosfomycin (Monurol):** Single 3g dose **Pain Relief:** - Phenazopyridine for burning (max 2 days) - NSAIDs (ibuprofen) for pain and inflammation - Heating pad for pelvic discomfort **Complicated UTI or [Kidney Infection](/condition/kidney-infection):** - Longer antibiotic course (7-14 days) - May require different antibiotics (fluoroquinolones) - Severe cases need IV antibiotics in hospital **Recurrent UTIs (3+ per year):** - Low-dose preventive antibiotics - Post-coital antibiotic (single dose after sex) - Vaginal estrogen (postmenopausal women) - D-mannose supplements (some evidence) - Cranberry supplements (prevention, not treatment) **Important Notes:** - Always complete the full antibiotic course - Symptoms should improve within 24-48 hours - If no improvement in 2-3 days, contact doctor - Untreated UTIs can lead to [kidney infection](/condition/kidney-infection)