7. Normal Host Defences which prevent UTI
URINARY :
Acidic pH
The concentration of urea in urine
TAMM-HORSFALL protein
Commensal flora
Exfoliation of the uroepthelium when
the bacteria adheres to the mucosa
Mechanism flushing during urination.
MUCOSAL:
Urothelial secretion of cytokines
Mucosal Immunoglobulin A
8. CLASSIFICATION of UTI
• On the basis of anatomical involvement :
• Other relevant classifications :
UTI
LOWER UTI UPPER UTI
URETHRITIS CYSTITIS PROSTATITIS PYELONEOHRITIS RENAL/ PERIRENAL ABSCESS
Level of complexity Type of infection Symptoms of infection
UNCOMPLICATED UTI ACUTE UTI SYMPTOMATIC UTI
COMPLICATED UTI CHRONIC UTI / RECURRENT UTI ASYMPTOMATIC UTI
9. Lower UTI versus Upper UTI
LOWER UTI
•Includes: URETHRITIS, PROSTATITIS and
CYSTITIS
•Mainly by the sexually transmitted
pathogens.
•SYMPTOMS:
Dysuria
Frequency
Urgency
Suprapubic pain and tenderness
UPPER UTI
•Includes: URETERITIS and
PYELONEPHRITIS
•SYMPTOMS:
Fever
Flank pain
Costovertebral angle tenderness
10. How to elicit costovertebral angle tenderness?
Have the patient sit upright facing
away from you or have him lie in
the prone position
Place the palm of your left hand
over the left CVA
Strike the back of your left hand
with the ulnar surface of your right
fist
Repeat this percussion technique
over the right CVA.
A patient with CVA tenderness will
experience intense pain.
D/D : Pyelonephritis, Renal calculi, Polycystic
Kidney Disease, UTI, Urinary obstruction, Costochondritis,
Appendicitis, Rib fracture, Abdominal abscess, Shingles, PID
11. Complicated UTI versus Uncomplicated UTI
COMPLICATED UTI
•Seen in patients who have functional and
anatomical obstacles to the the flow of
urine like:
Functional : Neurogenic bladder
Anatomical : Stones, Malignancies,
Strictures.
1. UTI in men, pregnant, and children
2. UTI in diabetics and immunodeficients
• Polymicrobial infection
UNCOMPLICATED UTI
•Seen in patient who have structurally
and neurologically normal urinary tract.
•Monomicrobial infection.
12.
13. KASS’s concept on Significant bacteriuria
The kass criteria for significant bacteriuria was introduced by “Edward Kass”
who was a medical researcher on infection.
According to the criteria, for a urine sample to be indicative of infection, there
must be significant bacteriuria.
The numbers of bacteria in voided urine is much more due to the
contamination while passing through the anterior urethra, even when the
urine is collected while taking all the precautions to prevent the
contamination.
SIGNIFICANT BACTERIURIA:
1. Suprapubic aspirate : 1 colony
2. Catheter sample: more than or equal to 10^2 CFU/ml
3. Clean catch mid stream urine
• For asymptomatic: more than or equal to 10^5 CFU/ml
• For symptomatic females: more than or equal to 10^2 CFU/ml
• For symptomatic males: more than or equal to 10^3 CFU/ml
*this criteria is not
applicable for the
organism not known to
normally cause
ascending UTI such as:
S.aureus, S. typhi,
Candida, MTB (even 1
colony is significant)
14. WHAT IS ACUTE URETHRAL SYNDROME ??
•Sypmptomatic
•Less Bacteriuria
15. DIAGNOSIS OF UTI
Urine specimen:
Suprapubic aspirate (gold standard urine sample)
Straight catheterization/ in and out catheterization
Clean catch mid stream urine (CCMSU) (most commonly used method)
Instructions for CCMSU collection:
- Clean the periurethral area
- Discard the first 10-30 ml of urine (washes away the non adherant
colonizing bacteria of the distal urethra)
- Collect the 2nd midstream urine sample (this reflects the colonizing
bacteria of the bladder)
- Then we send for the processing of urine specimen:
Should be done within 2 hours of collection
Can be refrigerated for 24 hours.
Or urine transport tubes that contain boric acid upto 48 hours.
16. When should we not accept the specimens for diagnosis?
1. When the urine is transported in an enrichment broth.
2. Urine innoculated in broth media.
3. Urine sediment.
4. Specimen from Foleys catheter tips.
5. Urine stored unrefrigerated for more than 2 hours.
17. SCREENING TESTS
MICROSCOPY BASED:
1. Gram stain of uncentrifuged /
unspun urine. 10 ^ 5 CFU/ml
2. Pyuria : detection of pus
cells/WBCs; 10 leucocytes/ ml is
indicative of infection. It is less
specific for the diagnosis of UTI.
But had best negative prognostic
value (NPV)
ENZYME BASED
1. Leucocyte esterase test: for the
detection of pus cells/ WBCs in
the urine sample.
2. Griess Nitrite test: detects nitrate
reducing bacteria like
enterobacteriaceae family.
*both have good negative predictive
value*
•Screening test can give information on the same day, but has
poor sensitivity at levels below 10^5 CFU/ml.
•The screening test is not acceptable for the urine collected by
suprapubic aspiration or catheterization.
18. Treatment of UTI
UNCOMPLICATED pyelonephritis in women UNCOMPLICATED cystitis in
women
Urine culture with AST Assess severity
High grade fever
Dehydrated
Severe flank pain
•Hospitalization
•Start the patient on Parenteral
empirical antibiotic
Ceftriaxone + Aminoglycosides/
Etrapenem
Mild case
Oral empirical
antibiotics
Oral empirical antibiotics:
•Nitrofurantoin x 5 days
•Fosfomycin once
•Cotrimoxazole x 3 days
No improvement / recurrence
Urine culture with AST
Fluoroquinolone x 5-7 days
+/- IM Ceftriaxone/
Etrapenem once
19. • COMPLICATED UTI:
Should be treated after urine culture with AST report
• ASYMPTOMATIC BACTERIURIA IN PREGNANT:
Urine culture with AST.
Beta-lactam to which the isolate is susceptible
• ASYMPTOMATIC BACTERIURIA before traumatic genitourinary procedure:
Urine culture with AST.
Start appropriate antibiotics 12 hours before procedure.
21. Foley’s Catheter
3 way foley’s catheter
Yellow = 10 fr
White = 12 fr
Green = 14 fr
Orange = 16 fr
Red = 18 fr
•INDWELLING catheter
•Balloon port, urine port, balloon
•Sizing on the basis of french grading
•Constitutes the outer circumference
•Not the outer diameter
•French scale = 2 x pie x r
•Diameter can be calculated by
dividing the french scale by 3
•Additional Irrigation port
23. CA-UTI
• Most common Health care associated infection (35-40%)
• Risk increases by 3-10% everyday with indwelling catheter
ROUTES
Introduction at the time of insertion
Flushing out mechanism circumvented
Ascent via the catheter – urethral mucosa interface
Via the pool of bacteria from the drainage bag intraluminally
Via the contaminated hands of health personnel
24. Criteria for the diagnosis of CA-UTI
1. Patient is catheterized or has had a urinary catheter removed within 48 hours.
2. Culture growth of more than or equal to 10 ^ 3 CFU/ml of uropathological bacteria.
3. Signs / symptoms of UTI:
• Feeling of need to urinate
• Suprapubic tenderness/ pain
• New onset fever/ worsening fever
• Rigors
• Flank pain
• Costovertebral angle tenderness
• Hypotension
4. No other alternative explanation for the above S/S, even with adequate evaluation.
25. Treatment of CA-UTI
MILD ILLNESS
•Able to tolerate oral therapy
•Treatment duration = 5-10 days
Ciprofloxacin / Levofloxacin / Cotrimoxazole
/ Amoxiclav
Add single dose of:
Ceftriaxone 1 gm IV/IM
Or
Ertapenem or Carbapenem IV
Or
Gentamicin / Amikacin / Tobramycin IV/IM
MODERATE ILLNESS
•Treatment duration = 5–10 days
Ciprofloxacin / Levofloxacin IV
Ceftriaxone / Cefepime IV
Piperacillin with Tazobactam IV
Ertapenem / Meropene IN
Gentamicin with or without Ampicillin IV
*transition to oral medication as soon as
possible
26. References:
1. Essentials of MEDICAL MICROBIOLOGY
2. Bailey and Loves’s Short Practice of Surgery
3. Harrison’s Principles of Internal Medicine
4. Essentials of Human Anatomy by AK Dutta
5. Davidsons’s principle and practice of Medicine
6. https://www.healthline.com
7. https://medlineplus.gov
8. https://www.ncbi.nlm.nih.gov
9. Google images
