1. URINARY TRACT INFECTION
Dr.Mohammed Sharique Ahmed Quadri
Assistant professor
Almaarefa College

2. LEARNING OBJECTIVES
Cite organisms most responsible for urinary tract infections (UTIs) and state why urinary catheters, obstruction, and reflux predispose to infections. 
List three physiologic mechanisms that protect against UTIs. 
Compare the signs and symptoms of upper and lower UTIs.
Describe factors that predispose to UTIs in children, sexually active women, pregnant women and older adults.
Compare the manifestations of UTIs in different age groups, including infants, toddlers, adults, and older adults.
Cite measures used in the diagnosis and treatment of UTIs.

3. ANATOMY

4. Urinary Tract Infections
UTI Includes
Asymptomatic bacteriuria
Symptomatic lower UTI e.g. Acute cystitis
Upper UTI e.g. Acute pyelonephritis

5. Epidemiology of UTI
UTI is more common in females (1-2% of young non-pregnant women)
40% of females will have a symptomatic UTI in their life time.
In men: prevalence is 0.04%.
Incidence of UTI increases in old age (10% of men & 20% of women)

6. Routs of infection
Ascending infection from the urethra is the most common route. Pyelonephritis most commonly results from ascent of infection up the ureter.
Hematogenous spread to the urinary tract is uncommon, the exceptions being tuberculosis and cortical renal abscesses.
Lymphogenous spread is rare.
Direct extension from other organs may occur, especially from intraperitoneal abscesses in inflammatory bowel disease or pelvic inflammatory disease.

7. Risk factors for UTI In Females: In Males:
sexual activity ,use of spermicidal, diaphragm
Pregnancy.
Estrogen deficiency (Post menopausal )
In Males:
lack of circumcision,
prostatic hypertrophy,

8. Risk factors for UTI In both sexes : Obstruction,
Vesicoureteric reflux,
Instrumentation, & catheterization
Neurogenic disorders that impairs bladder, emptying
Diabetes (increase risk of complications and fungal infections)

9. Risk factors for UTI
Obstruction : any microorganism that enter the bladder is washed out during voiding.
When outflow is obstructed
Urine remains in bladder – medium for microbial growth
Increase pressure in bladder- compresses vessels in bladder wall- decrease in the mucosal defense

10. Risk factors for UTI Obstruction : Anatomic Obstruction
Stones
Prostatic hyperplasia
Pregnancy
Malformation of ureterovesical junction
Functional obstruction
Neurogenic bladder
Infrequent voiding
Constipation
Detrusor muscle instability

11. Risk factors for UTI
Urethrovesical reflux : urine from urethra moves into bladder
In women during coughing or squatting
Voiding abruptly interrupted
Vesicouretral reflux: occurs at the level of bladder and ureter
Due to abnormality at the junction of ureter & bladder
Associated with pyelonephritis and infection of upper urinary tract

12. Risk factors for UTI CATHETER INDUCED INFECTION:
Provide A means for entry of microorganisms into the urinary tract
Bacteria adhere to surface of catheter & initiate the growth of biofilm that covers the surface of catheter.
Biofilm protects the bacteria from antibiotics

13. Etiological Factors Uncomplicated Lower UTI Complicated UTI
Escherichia Coli
Staphylococcus saprophyticus
Complicated UTI
Proteus mirabilis
Klebsiella species
Enterobacter species
Pseudomonas aeruginosa
Staphylococcus aureus (gram- positive cocci)
Gram negative rods

14. Pathogenesis of UTI
PATHOGEN VIRULANCE
HOST DEFENSES
Pathogenesis of UTI involves interaction of host with agent .leading to letdown of host defenses against virulence of infectious agents

15. Pathogenesis of UTI Host Defenses:
Urinary bladder is usually resistant to bacterial colonization.
Host defences of bladder have many components.
Washout Phenomenon: Bacteria removed during voiding
Protective mucin layer: Protects against bacterial invasion
Immune mechanisms: secretory immunoglobulin(IgA), PMN cells
Normal flora in periurethral area in women and prostatic secretion in males

16. Pathogen Virulance
Only those strains of E-coli with increased ability to adhere to epithelial cells , produce UTI
Most E.coli causing UTI belong to O,K and H serotypes.
Uropathogenic E.coli virulence factors: - Have fimbria /Pilli (for adherence). - Secrete hemolysin & aerobactin.
- Resist serum bactericidal action.

18. Pathogenesis of UTI
Periutheral area & urethra are colonised by bacteria.
Bacteria enter bladder in susceptible host.
Adherence properties enable pathogens to colonise bladder.
Pathogens attach to uroepithelial mucosa  secretion of cytokines  recruitment of PMNs  inflammation.
Pathogens may ascend through ureter to kidney  pyelonephritis.

19. Clinical presentation of UTI
Asymptomatic bacteriuria:
Common in females & elderly.
25% develop symptomatic UTI .
25% clear spontaneously.
Spontaneous cure & reinfection are common.
Cystitis:
Frequency, dysuria , urgency.
Suprapubic discomfort +/- tenderness.
Fever is often absent.
Ocasionally urine is cloudy and foul smelling

20. Clinical presentation of UTI
Acute pyelonephritis:
Fever, abdominal pain, vomiting.
Dysuria ,frequency, flank or loin pain.
Flank or loin tenderness.
In elderly: symptoms are often atypical.
Bacteremia is common.

21. UTI in Special Populations

22. UTI in Pregnant women
Changes occurring in urinary tract during pregnancy predispose to UTI
Dilation of calyces, pelvis and ureters.
Reduction in peristaltic activity of ureters (thought to be muscle relaxing effect of progesterone and mechanical obstruction from enlarge uterus)

23. UTI in Pregnant women Complications: Persistent bacteriurea
UTI during pregnancy may be the result of preexisting asymptomatic bactriurea
Urine culture is recommended at first prenatal visit
Acute or chronic pyelonephritis
premature delivery.
low birth weight infant.
Increased newborn mortality

24. UTI in Children

25. Frequency of UTI
UTI is more frequent in females than males at all ages with the exception of the neonatal period.
Uncircumcised males have a higher incidence than circumcised males.
Uncircumcised male infants have a higher incidence of UTI than female infants.

26. Frequency of UTI
Excluding neonates, females younger than 11 years have a 3-5% risk; boys of the same age have a 1% risk.
UTI is the source of infection in up to 6-8% of febrile infants in the first 3 months of life.

27. Clinical Features vary with the age of the patient.
Symptoms in Neonates:
Hypothermia or fever
Failure to thrive
Poor feeding
Vomiting
Symptoms in Infants:
Fever
Vomiting, diarrhea
Strong-smelling urine

28. Clinical Features Preschoolers School-aged children
Vomiting, diarrhea, abdominal pain
Fever
Strong-smelling urine, enuresis, dysuria, urgency, frequency
School-aged children
Vomiting, abdominal pain
Strong-smelling urine, frequency, urgency, dysuria, flank pain, or new enuresis
Adolescents are more likely to have some of the classic adult symptoms.

29. Complications
Even in the absence of urinary tract abnormalities, cystitis may lead to vesicoureteral reflux, and it may worsen a pre-existing reflux.
Untreated reflux causes pyelonephritis. Chronic or recurrent pyelonephritis results in renal damage and scarring that may progress to chronic renal failure.
Prevalence varies based on age and sex

30. UTI IN ELDERLY

31. UTI IN ELDERLY
Second most common cause of infection after respiratory tract infection.
Predisposing factors:
Immobility leading to poor bladder emptying
Obstruction (BEP, stones)
Bladder ischemia caused by urinary retention
Constipation
Senile vaginitis
Other problems necessitating catheterisisation.

32. UTI IN ELDERLY Varying symptoms.
Difficult to interpretate because elderly people without UTI also commonly experiences, urgency, frequency and incontinence.
May have vague symptoms like
Anorexia
Fatigue
Weakness

33. DIAGNOSIS

34. Diagnosis of UTI Urine microscopy: -WBCs, RBCs
Urine dipstick: more markers of infection

35. Diagnosis of UTI Urine culture & sensitivity to antibiotics
Significant bacteriuria= cfu/ml
symptoms: 1 +ve cuture = infection
Symptoms: cfu/ml = propable infection
Asymptomatic: 2 +ve cultures = infection
False negative : antibiotics, antiseptics, diuresis.

36. Diagnosis of UTI Others CBC, BLOOD CULTURE KIDNEY FUNCTION TEST X-ray
Ultrasonography
CT scan
Renal scans
Used to identify Contributing factors like obstruction