Urinary Tract Infections

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 • 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. RecurrentRelapse Vs. Reinfection Relapse  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)VsUpper 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 InfectionPhysiologic Changes

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

22. Risk Factors ??????

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

29. Organisms ??????

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

31. Organisms Gram Positive Organisms • Staphylococcus Aureus • Staphylococcus Epidermidis • Streptococcus Feacalis

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

33. Rout of Infection ??????

34. Rout of Infection • Ascending Infection. • 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. • 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 ??????

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 ??????

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 ??????

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 ??????

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. Investigation Clinical Symptoms Plus Suggestive Dipstick Plus 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%).