Transcript Definition,Prevalence,Route of infection,Causative agents of UTIs

This lecture was conducted during the Nephrology Unit Grand
Ground by Medical Student under Nephrology Division under
the supervision and administration of Prof. Jamal Al Wakeel,
Head of Nephrology Unit, Department of Medicine and Dr.
Abdulkareem Al Suwaida, Chairman of Department of
Medicine and Nephrology Consultant. Nephrology Division is
not responsible for the content of the presentation for it is
intended for learning and /or education purpose only.
Presented By:
Dr. Nasser Al Faqih
Medical Student
2009
Definitions

UTI : is currently defined as the inflammatory response of the
urothelium to bacterial invasion it is usually associated with lower
or upper urinary tract infection symptoms

Bacteriuria: is the presence of the bacteria in the urine

Pyuria : is the presence of white blood cell (pus cell) in urine



Uncomplicated UTI: is the one occurring in a patient with a
structurally and functionally normal urinary tract
Complicated UTI: is the one occurring in the presence of an
underling anatomical or functional abnormality
UTI may be isolated , recurrent or unresolved
Prevalence of urinary tract infections (UTI)

Females are much more affected than males

It is estimated that half of all women will have at least one UTI in their live.

the risk of UTI in women increases after menopause

after a UTI 20 - 40 % will have a recurrence

the recurring infections are usually reinfections.

asymptomatic bacteriuria in women occurs in

2.7% of 15 - 24 years old

9.3% of over 65 years old and

20 - 50% of over 80 years old
Prevalence of UTIs


UTI is rare in young and middle-aged men
UTI in men is often associated with :
underlying pathology
catheterisation
urological procedures.

urinary catheter increases the risk of UTI
- because it may introduce infection or the bacteria colonise the catheter
- pseudomonas is commonly encountered organism
Route of infection

Ascending infection




Bacteria in perineal area ascends
through the urethra, enters the
urinary bladder and multiplies
This is the most common route of
infection
e.g. E.coli to the bladder
Haematogenous infection


In a patient with bacteremia,
bacteria may be “seeded” into the
kidneys from the blood
e.g. staph .aureus , T.B
Causative agents of UTIs
Risk factor
Women in general
Pregnant women
Sexually active women
abnormality of normal flow of urine
Enlarged prostate
Kidney stones
Vesicoureteral reflux
Neurogenic bladder
indwelling urinary catheters
compromised immune function
diabetes
immunosuppressive drugs
Clinical features of UTI

Cystitis
 Frequency
 Urgency
 Dysuria
– painful voiding
 suprapubic Pain
 Cloudy or foul-smelling
urine
Clinical features of UTI

Acute pyelonephritis
 Loin
 High
pain and tenderness
Fever and chills
 Nausea
 malaise
and vomiting
INVESTIGATION OF UTI

Midstream urine (MSU) for:
dipstick for nitrite
microscopy for WBCs & RBCs
urine culture
If sterile pyuria is detected then T.B has to be considered in the differential diagnosis
INVESTIGATION OF UTI cnt ..

Further investigation if underlying cause is suspected :
- symptoms of upper UTI
- recurrent infection
- pregnant women
- unusual infected organism e.g. proteus
INVESTIGATION OF UTI cnt ..

Further investigations include , as
indicated by the clinical condition of the
patient ,the following:
- CBC
- Blood culture
- Plain KUB
- Ultrasound
- IVU or CT urogram
- Cystoscopy
Treatment of UTI




Antimicrobials are the mainstay of treatment
The choice of antimicrobial depend on the diagnosis, the clinical
condition of the patient and the organism isolated .
Dose , route and duration of antimicrobial depend on the diagnosis
and severity of infection
Treatment of underlying cause if present
- e.g. stones , obstruction , reflux ….etc
Treatment of UTI

Commonly used antimicrobials include :
- trimethoprim
- cotrimoxazole
- quinolones
- nitrofurantoin
- cephalosporin
- ampicillin , amoxicillin
- aminoglycosides
- fluconazole for fungi
Treatment of UTI
Acute uncomplicated cystitis:




trimethoprim for 3 days
Cotrimoxazole for 3 days
Quinolones for 3 days
nitrofurantoin for 7 days
Acute Uncomplicated pyelonephritis:
□
□
□
□
Ciprofloxacin for 7- 10 days
Cephalosporin for 7- 10 days
Amoxicillin for 7-10 days
Aminoglycosides 7-10 days
UTI IN CHILDERN





A common pediatric problem
Girls are more affected than boys
May indicate an underlying cause
Reflux and other abnormalities
need to be excluded
Treatment :
- treat the infection
- investigate for possible
underlying cause
- ? Need for prophylaxis
- treat the underlying cause if
present