1. Urinary Tract Infections

2. I would like to tell you something…Will you listen to me…?

4. Overview of UTI 7 million office visits yearly
1 million hospitalizations
About 2/3rds of patients are women
40% to 50% of women have UTI at some point during their lives
Important complications of pregnancy, diabetes mellitus, polycystic disease, renal transplantation, conditions that impede urine flow (structural and neurologic)

5. Terms Urinary tract infection Significant bacteriuria
Asymptomatic bacteriuria
Acute pyelonephritis
Chronic pyelonephritis
Chronic interstisial nephritis
Pyuria
Urethral syndrome

6. UTI: the finding of microorganisms in bladder urine with or without clinical symptoms and with or without renal disease
Women: Presence of at least 100,000 colony-forming units (cfu)/mL in a pure culture of voided clean-catch urine.
Men: Presence of just 1,000 cfu/mL
Significant bacteriuria: the number of bacteria in the voided urine exceeds the number that can be expected from contamination (i.e. ≥ 10⁵ cfu/ml)

7. Asymptomatic bacteriuria: Significant bacteriuria (>105 cfu/ml) without clinical symptoms.
Acute bacterial pyelonephritis: a clinical syndrome of fever, flank pain, and / or tenderness

8. Chronic bacterial pyelonephritis: Long- standing infection associated with active bacterial growth in the kidney; or the residum of lesions caused by such infection in the past
Chronic interstitial nephritis: renal disease with histologic findings resembling chronic bacterial pyelonephritis but without evidence of infection

9. Pyuria: the presence of pus (WBC’s) in urine, which may or may not be caused by UTI. The preferred method for quantification is enumeration in unspun urine. The leukocyte esterase nitrite test has a sensitivity of between 70% and 90% for symptomatic UTI
Urethral syndrome: characterized by frequency, dysuria, and suprapubic discomfort without demonstrable infection

10. Some Classifications of UTI

11. Presentation of UTIs Urethritis Cystitis Haemorrhagic cystitis
The inflammation and infection is limited to the urethra
It is usually a sexually transmitted disease.
Present in men and women
Cystitis
Irritation of the lower urinary tract mucosa (i.e. bladder)
Dysuria (painful urination)
Urgency & frequency but small
Suprapubic tenderness
Pyuria
Haemorrhagic cystitis
Large quantities of visible blood in the urine
Caused by an infection (bacterial or viral)
Irritation when voiding
Pyelonephritis
Kidney infection from lower UTI infection
Complications – Sepsis, septic shock and death

12. Uncomplicated vs Complicated UTI
Uncomplicated UTI: infection that occurs in a structurally and neurologically normal urinary tract
Females > Males
Complicated UTI: infection in a urinary tract with functional or structural abnormalities (including indwelling catheters and renal calculi)
Females = Males
In elderly men are always considered complicated
In women are complicated when:
Hx of recurrent UTI
Secondary to structural abnormalities
Catheters
Stones
Urinary retention
Abscess formation or urosepsis

13. Primary Vs. Recurrent Primary UTI
Infection that occurs in the urinary tract for the first time. No previous episodes of infections.
Recurrent UTI
Presence of past history of urinary tract infection

14. Recurrent Relapse Vs. Reinfection
Recurrence within 2 weeks of treatment and mainly due to treatment failure, the initial organism is not totally cleared.
The Same Organism
Occurs in case of:
Acute Upper UTI.
Presence of obstruction like stone disease.

15. Reinfection
Recurrence within several weeks after the antibiotic therapy has cleared up the initial episode.
Different Organisms

16. Lower Urinary Tract Infection (Urethritis and Cystitis) Vs Upper Urinary tract Infection (Pyelonephritis)

17. Acute Uncomplicated Cystitis
Acute bacterial cystitis is usually characterized by sudden onset, multiple urinary symptoms, pyuria, and sometimes hematuria
Acute dysuria in young women usually indicates: acute bacterial cystitis; the urethral syndrome; or vaginitis
Although most patients have lower urinary symptoms only, 30% to 50% may have subclinical renal involvement
Causes: E. coli (80%), S. saprophyticus (10% to 15%), and occasionally Klebsiella, Proteus mirabilis, and other microorganisms.

18. Acute Uncomplicated Pyelonephritis
Largely a clinical diagnosis
Pyuria is usually present; about 20% have positive blood cultures; causative organisms the same as with cystitis
Predisposing factors: structural abnormalities; strains of E. coli with unique markers; genetically-determined carbohydrate receptors on uroepithelial cells
Highly significant!
Presence of WBC casts suggests pyelonephritis

19. Urinary Tract Infection Physiologic Changes
Physiologic changes with aging in the urinary tract
Age-Related Changes
Men
Women
Decreased bladder capacity and increased urine production (especially at night)
Decreased voided volume
Decreased estrogen w/menopause leads to thinning of vaginal & urethral mucosa
Decreased lower urinary tract sensory threshold √
Palmer, 2004

20. Physiologic changes with aging in the urinary tract
Age-Related Changes
Men
Women
Problems of urinary storage & emptying
↑incidence of overflow incontinence from urethral obstruction or stricture
Decreased estrogen levels leads to pH changes in vagina, favoring colonization of E. coli, ↑risk of UTI
Prostatic enlargement can lead to urinary obstruction, increased residual urine & infection √
Palmer, 2004

21. Urinary Tract Infections
Risk Factors
Organisms
Rout of Infection
Symptoms - History
Signs – Physical Exam
Differential Diagnosis
Investigation
Treatment
Complications

22. Risk Factors
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23. Risk Factors General Conditions Diabetes
Previous urinary tract infection
Kidney Problems
Immunosuppression
Sickle Cell Disease
Functional or mental impairment
Urinary Stone Disease
Urinary Tract Anomalies
Neurogenic Bladde
Urologic instrumentation or surgery
Urethral catheterization
Renal transplantation
spinal injury

25. Risk Factors Specific for Females Structure of Urinary Tract.
Sexual Behavior. It is not STD
Contraception.
Pregnancy
Menopause

26. Risk Factors Specific for Males Benign Prostatic Hypertrophy
Prostatitis

27. Risk Factors Specific for Children Uncircumcised Males
Vesicoureteral Reflux Disease.

28. (Male – shaded area; Female – line)
Frequency distribution of symptomatic UTI and prevalence of asymptomatic bacteriuria by age and sex
(Male – shaded area; Female – line)

29. Organisms
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30. Gram Negative Organisms
E.Coli In Acidic Urine (most common)
Proteus In Alkali Urine
Klebsiella
Citrobacter
Pseudomonas

31. Gram Positive Organisms
Staphylococcus Aureus
Staphylococcus Epidermidis
Streptococcus Feacalis

32. Organisms Fungal Infections Mainly in Diabetic Patients.
Candida Species

33. Rout of Infection
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34. Rout of Infection Ascending Infection. Lymphatic Spread. Local Spread.
The common route of nearly all forms of urinary tract infection (bacteria initially colonize periurethral tissues)
Common in females than in males because of shorter urethra
Single bladder catheterization can result in UTI in 1% of the ambulatory population
Lymphatic Spread.
Increase bladder pressure can cause lymphatic flow to be directed toward the kidney
Local Spread.

35. Rout of Infection Hematogenous Spread. Descending From the Kidneys
Frequently seen with Staphylococcus aureus bacteremia or endocarditis
Also seen to occur in experimental models with Candida
Infections with gram negative bacilli rarely occurs by this route
Descending From the Kidneys
Local Spread.

36. Symptoms - History
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37. Symptoms - History Lower Urinary Tract Infection Frank Hematurea.
Painful Micturation.
Discomfort in the lower abdomen.
Urinary Frequency.
Urinary Urgency.

38. Symptoms - History Upper Urinary Tract Infection
High Grade Fever, chills and rigor.
Flank Pain.
Nausea and Vomiting
Lower UTI Symptoms.

39. Signs – Physical Exam
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40. Signs – Physical Exam Vital Signs Suprapubic Tenderness
Flank Tenderness

41. Based on the symptoms both
a clinical diagnosis of a UTI and a differentiation between lower (cystitis) or upper (pyelonephritis) UTI should be made

42. Differential Diagnosis
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43. Differential Diagnosis
Lower UTI
Stones.
Vaginitis and STD
Interstitial Cystitis.
Menopausal Changes.
Prostate Disease.

44. Differential Diagnosis
Upper UTI
Pneumonia.
Cholecystitis.
Appendicitis.
Kidney Stones.

45. Investigation
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46. Investigation Dipstick Test Nitrites Test Leukocyte Esterase Test.
Blood.
Proteins.

47. Investigation Microscopic Examination WBC’s Count. RBC’s Count.
Cellular and Hyaline Casts.

48. Suggestive Microscopic Exam Urinary Tract Infection (75%)
Investigation
Clinical Symptoms
Plus
Suggestive Dipstick
Suggestive Microscopic Exam
Equal
Urinary Tract Infection (75%)

49. Investigation Gram Stain and Urine Culture
Urine culture is gold standard.
Used in every positive dipstick and urinalysis.
Used in negative dipstick and urinalysis if: - Age less than 2 Years.
- UTI symptoms (25%).

51. Investigation Helpful Laboratory Tests CBC Serum Electrolytes KFT
Blood Culture.

52. Investigation Recurrent cases of pyelonephritis Imaging Studies
Structural abnormalities are suspected.
No response to treatment.
Suspicion of obstruction.
Children: age months

53. Investigation Ultrasound Screening for hydronephrosis. Kidney Stones.
Kidney Abscess.

54. Investigation
Nuclear Scan
Kidney Scar.

55. Investigation X-rays Stones. Structural Abnormalities.
Urethral Narrowing.
Incomplete Bladder Emptying.
Examples: - MCUG - IVP and KUB

58. Treatment Upper UTI Good Hydration.
Oral TMP-SMX or Quinolones for 2 weeks.
Oral amoxicillin and clavulanic acid for 2 weeks.

59. Treatment Lower UTI Good Hydration.
Oral TMP-SMX or Quinolones for 1 week.
Relapses are best treated with the same AB, long period.

63. Treatment Reinfections Long term AB prophylaxis.
Surgical reimplantation of the ureters >>> VUR disease

64. Treatment Failure of Treatment Compliance and AB Dose.
Bacterial Resistance.
Polymicrobial UTI.
Azotemia.
Papillary Necrosis.
Staghorn Calculi.

65. Prophylaxis of recurrent cystitis with antimicrobial agents
prophylaxis should be considered when more than 3 infections per year
prophylaxis to continue for 6 months
if infections recur after prophylactic treatment, the prophylaxis is re-commenced for 6 – 12 months

66. Drugs of choice in UTI prophylaxis
First choice:
trimethoprim 100 mg in the evenings
nitrofurantoin mg in the evenings
Second choice:
methenamine hippurate 1 g twice daily
norfloxacin 200 mg daily or on 3 evenings per week
nitrofurantoin (not if serum creatinine is above 150 μmol/l)
quinolones (in cases where there is no response with other prophylactic medication or tolerance to other medications is poor)
During pregnancy:
nitrofurantoin 50 mg daily or
methenamine hippurate 1 g daily for the rest of the pregnancy
particularly if recurrent bacteriuria is diagnosed in early pregnancy

68. Complications
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69. Complications
Spread of Infection - Sepsis. - Prostatitis. - Epididymitis.
Persistence of Infection - Perinephric Abscess. - Chronic Infection.

70. Complications
Obstruction.
Kidney Scar.
Kidney Stones

71. That will be all … thanks for not falling asleep ;)
Bye Bye