This is a series of lectures on microbiology, useful for undergraduate medical and paramedical students

1. Urinary Tract Infection
Dr. Ashish Jawarkar, M.D.

2. Urinary tract

3. Urinary Tract Infection

Upper urinary tract Infections:
Pyelo-nephritis
 Ureteritis


Lower urinary tract infections
Cystitis (“traditional” UTI)
 Urethritis (often sexually-transmitted)


4. Ascending UTI

5. Descending infection
Hematogenous spread
 Chronically ill or immunosuppressed
patients


6. Causes
Stasis of urine (enlarged prostate etc.)
 Sexual activity
 Pregnancy
 Catheterisation
 Stones


7. 5-7% pregnant women may present
without symptoms
 May lead to prematurity and perinatal
death
 Hence mandatory to screen all pregnant
women


8. Symptoms of Urinary Tract Infection

UPPER UTI
Dysuria (burning micturition)
 Increased frequency


LOWER UTI
Fever
 Flank pain


9. Agents of UTI
Most common – E coli
 Community acquired

E. coli
 Enterobacter


Hospital acquired
Klebsiella
 S. aureus
 Pseudomonas


10. Lab diagnosis
Urine can get contaminated while
passing
 Sterile wide mouthed container
 Mid stream clean catch specimen
 First portion – bacteria from distal
urethra
 Processed within 2 hours


12. Significant bacteriuria
>1,00,000 bacteria per ml
 Counts <1000 are due to contamination
 Counts between 1000 and 1,00,000 may
be significant, have to be co related
clinically and by repeat culture


13. Other methods for collection

Suprapubic aspiration

14. 
Percutaneous nephrostomy

15. 
catheter

16. Culture
Blood agar
 Mc conkey agar


17. Antibiotic susceptibility testing

18. Screening tests
Nitrite test
 TTC test
 Demonstration of bacteria in wet film


19. Wet mount

20. Strips

21. Family enterobacteria

Include
E. coli
 Klebsiella
 Proteus


22. Escherichia Coli
Named after Escherich who first
discovered the colon bacillus
 Lives in intestine, passed in feces


24. Test for contaminated water supply

E coli testing in water

25. 
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Morphology
Growth characteristics
Biochemical reactions
Resistance
Pathogenicity and virulence
Epidemiology
Diseases caused
Laboratory diagnosis
Treatment

26. Morphology
Gram negative rod
 Singly or in pairs
 Motile


28. 
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Morphology
Growth characteristics
Biochemical reactions
Resistance
Pathogenicity and virulence
Epidemiology
Diseases caused
Laboratory diagnosis
Treatment

29. Growth characteristics
Good growth on ordinary media
 Hemolytic on blood agar
 Mac conkeys agar, pink colonies


30. Blood agar

31. Mac conkey’s medium

32. 
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Morphology
Growth characteristics
Biochemical reactions
Resistance
Pathogenicity and virulence
Epidemiology
Diseases caused
Laboratory diagnosis
Treatment

33. IMViC test
I - Indole
 M - Methyl red
 Vi - Voges-Proskauer
 C - Citrate utilisation

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To differentiate between enterobacteria

35. Klebsiella IMViC

36. 
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Morphology
Growth characteristics
Biochemical reactions
Resistance
Pathogenicity and virulence
Epidemiology
Diseases caused
Laboratory diagnosis
Treatment

37. Resistance
Resistant to multiple antibiotics
 Due to production of beta lactamase
which inactivates penicillin and
cephalosporins
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38. 
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Morphology
Growth characteristics
Biochemical reactions
Resistance
Pathogenicity and virulence
Epidemiology
Diseases caused
Laboratory diagnosis
Treatment

39. Pathogenicity and virulence

Surface antigens O and K
O antigen – prevents phagocytosis,
endotoxic activity
 K antigen – also protects against
phagocytoisis

Fimbria – important in UTI
 Toxins – beta lactamase


40. 
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Morphology
Growth characteristics
Biochemical reactions
Resistance
Pathogenicity and virulence
Epidemiology
Diseases caused
Laboratory diagnosis
Treatment

41. Epidemiology
Inhabit the colon
 Spread via contaminated water/food


42. Diseases caused

UTI

Precipitated by
Prostate enlargement
 Pregnancy
 Calculi

Peritonitis and bowel abcesses
 Meningitis in new born
 Septicemia


43. 
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Morphology
Growth characteristics
Biochemical reactions
Resistance
Pathogenicity and virulence
Epidemiology
Diseases caused
Laboratory diagnosis
Treatment

44. Treatment
Ampicillin + clavulanic acid
 Imipenem
 Meropenem
