URINARY TRACT INFECTION

(UTI)

BY: PROFESSOR SALIH BIN SALIH

URINARY TRACT

UTI

• Pyelonephritis (infec. In the kidney)

• Cystitis

• Urethritis

• prostatitis

• COMMONEST IS CYSTITIS & URETHRITIS, specially in women

• Cystitis is uncommon in young men.

NATURAL DEFENCES

Factors which prevent infection naturally

• Free flow of urine (no obstruction)
• Acidic urine (acidity kills bacteria)
• Complete bladder emptying (no stasis).
• Remember, stasis of urine is bad.
• Urinary tract epithelium secretes substances which are anti-bacterial.
• ANY BREAK IN THIS CHAIN CAN CAUSE UTI

RISK FACTORS

• Female gender
• Old age (even males)
• DM
• Structural abnormality of urinary tract (causes stasis) eg. diverticulum in the bladder or ureter
• Obstruction of the urinary tract (stone, BPH)
• Pregnancy (causes urine stasis)
• Foley’s catheter

WHAT IS COMPLICATED UTI?

If UTI occurs in the presence of any of these: a) Anatomical abnormality in the urinary tract b) Stones in the tract c) DM d) Poor immunity (eg HIV, patient on long term ______?) e) Presence of Foley’s catheter

If no, then its called an uncomplicated UTI

PATHOGENS CAUSING CYSTITIS

• E.Coli : Most common cause.
• Proteus(12%) Klebsiella (4%), Pseudomonas
• Staph. Saprophyticus(10%)
  • Normal flora of the female genital tract but can cause UTI also
• Candida Albicans (fungus): Causes UTI if immunity is low.

S/S OF CYSTITIS

• Dysuria, increased frequency, nocturia
• Suprapubic pain & tenderness
• Cloudy & very foul urine smell
• Fever uncommon in young patients
• In children ---⇒ fever more common

S/S IN OLD PATIENTS

• Typical signs & symptoms often absent
• Common S/S are:
  • Confusion, drowsy
  • Change in behavior, irritable
  • Not feeling well, anorexia, weakness
  • Incontinence

(any infection in old people can present with the above symptoms)

INVESTIGATIONS

INVESTIGATIONS

Urine analysis Urine C/S Imaging

1. Urinalysis : Take a clean, midstream, freshly voided sample (or catheter sample)

• Bacteria: ~ In females, 10⁵ /ml of urine diagnostic of ~ In males, 10² /ml of urine UTI

• Nitrite: positive (produced by bacteria)
• WBCs : more than 8-10/ high power field
• Leucocyte Esterase: positive (an enzyme produced by WBCs)
• RBCs : may be present or absent

2. DIPSTICK TEST ( a quick test but not ideal)

3. Urine C/S

   • Not recommended in every case
   • Result takes 48-72 hrs
   • Recommended in :
     • pregnancy
     • DM
     • recurrent UTI
     • Failure to respond to Rx

4. IMAGING: i.v.Pyelogram, u/s, CT (with contrast)

• Not done routinely

• Done in the following : a) Recurrent UTI : To find out any abnormality in the urinary tract eg stone, BPH, diverticulum

  b) In children (UTI is very rare in children, so if the have it, should rule out any structural abnormality)

i.v. pyelogram (I.V.P)

MANAGEMENT OF UTI

(MAINLY CYSTITIS)

1. Antibiotics
2. High fluid intake
3. Remove/replace catheter, if present
4. Cranberry juice(?)

Antibiotics are started empirically, then modified according to culture reports, if needed

A) YOUNG FEMALES WHO ARE NOT PREGNANT

• First choice : Tmp/Smx (Bactrim )DS, 1 tab. bid., or Nitrofurantoin or Fosfomycin
• Second choice : Ciprofloxacin (quinolones) (according to infec. Dis. Society of America)

ONE OF THEM, FOR 3 DAYS (resistance to cipro is very high in many countries)

B) FEMALES WHO ARE PREGNANT

1. 6% of preg. females have significant bacteria in urine, even without UTI symptoms. If not treated, it can cause pyelo-nephritis (can lead to maternal & fetal complications)
2. Routine urine C/S is done in the 1^st trimester
3. Rx is given even if no symptoms (asymp. bacteriuria)
4. Rx of choice : * Nitrofurantoin * Fosfomycin

TREAT FOR 7 DAYS (NOT 3 DAYS)

C) MALES:

• Same as A
• 7 day Rx (not 3 days)

In A) & C) no need to do a urine C/S after treatment.

D) Asymptomatic bacteriuria : Treat only :

• a) If the patient is pregnant
• b) If the person is going to have any urologic surgery( if the pre-op routine tests show bacteria in urine)

DURATION OF CYSTITIS TREATMENT

1. Non-pregnant female: 3 days
2. Males } 7 Days
3. Pregnant female } 7 Days
4. DM } 7 Days

PROPHYLAXIS FOR RECURRENT UTI

If a patient gets recurrent UTI, do the following:

1. Advise increased fluid intake
2. Frequent urination( to avoid stasis in the bladder)
3. Investigate for any urinary tract pathology (by ultrasound / pyelogram etc) & treat it
4. Do urine culture( to see if any antibiotic resistance is there)

Special situations

Chronic indwelling Foley’s catheter

• WBC & bacteria are almost always present
• No treatment if patient is asymptomatic
• Treat w/antibiotics only if symptoms present
• Change Foley’s catheter

ACUTE PYELONEPHRITIS

• It is infection of the renal parenchyma
• Mostly due to ascending infection from below
• S/S: Same as lower UTI + fever, loin pain
• Invest:
  • Urine analysis
  • *Urine C/S
  • Blood C/S, Imaging studies if needed
• Rx:
  1. Co-amoxiclav (Augmentin)
  2. Cipro/levofloxacin
  3. i.v. gentamycin, 3^rd gen. cephalosporins

Depending on the severity, patient may need oral or iv antibiotics.

SUMMARY

1. Commonest bacteria: E.Coli, then Klebsiella, Proteus
2. UTI more common in females
3. Treatment with antibiotics usually for 3 days
4. Treatment for 7 days in males, pregnancy, DM
5. In pregnancy, if bacteria are present in urine, treat it, even if asymptomatic
6. Obstruction in the urinary tract ---⇒ increased risk of UTI
7. Antibiotics used:

• Non-pregnant female: Bactrim, nitrofurantoin, fosfomycin, cipro
• Males: Same as above for 7 days * Pregnancy: Nitrofurantoin, fosfomycin