Urinary tract infection...dos and dons

1. URINARY TRACT INFECTION
Dr. Ajay Kumar Yadav
PGY1,Internal Medicine
IOM-TUTH, Kathmandu
2073/11/15

2. INTRODUCTION
• first documentation in the Ebers
Papyrus dated to 1550 BC
• About 150 million people per year
• more common in women than men.
• m/c form of bacterial infection in women

3. • Half of women having at least one infection at
some point in their lives
• Most frequent in female 20-36
• Risk increases after menopause
• 20-40 % have recurrenUp to 10% of women
have UTI in a given year

4. HOSPITAL ACQUIRED UTIs
• 600k / year
• 40% of hospital acquired infections
• CAUTIs – 80 % of hospital acquired UTIs
• Catheterisation increases risk by 10 fold
• Pyelonephritis common in pts catheterized
over a month.

5. GENDER AND SEX DIFFERENCES
• Neonate : M > F
• Adolescent to menopause : F > M
• Older age : M=F
• Female : short ureter , sexual contact and
spermicidal
• Male : prostate infections , circumcision ,
homosexuals , anatomical defects

6. Classification of UTI
• Location
Upper ( pyelonepritis , intrrenal and peri-
nephric abscess )
Lower ( cystitis , uretheritis )
• Symptoms
Asymptomatic
Symptomatic

7. • Recurrences
Sporadic < 2 /6 months
Reccurent >_ 2 /6 months or >_3/1year
• Complicating factors
Uncomplicated
Complicated
• Setting
Hospital acquired UTIs

10. • bacterial colonisation ( staph epidermidis ,
streptococcus sps , enterococcus etc ) is
confined to the lower end of the urethra and
the remainder of the urinary tract is sterile

11. ETIOLOGY
Common pathogens of UTI
E. Coli (80 % of outpatient UTIs)
Klebsiella
Proteus
Enterobactor
pseudomonas
Staph. Saphropyticus (5-15% )
Enterococcus
Candida
Adenovirus type 11

12. Pathogenesis

13. Pathogenesis of UTI
• Ascending route – m/c
• Initial event – colonisation of uretheral and
peri-uretheral tissues
• Once in bladder – multiplies – pass up ureter if
VUR – renal pelvis and parenchyma
• Healthcare infections – instrumentation
( catheterisation , cystoscopy )

14. • Hematogenous – less frquent ( MTB ,
salmonella )
• Common site of abscess formation in Staph.
aureus bacteremia , less often in candidemia
and rarely with gram negative
• Source of uropathogens – enteric bacteria

16. HOST PROTECTIVE FACTORS IN UTI
• Flushing mechanism
• Acidic pH of urine ( 4.6-6 ) – anti-bacterial
• Acidic vaginaal pH(3.5-4.5) – inhibits
colinization
• THF protein – blocks E.coli
• Chemotactic factors IL-8

18. Bacterial factors in UTI
• E.coli strains expressing O Ag – most of UTI
• Expressing capsular Ag – antipgagocytic –
clinical severity
• P-fimbriae – enhance attachment of E.coli to
uroepithelial cells
• Motility – ascend against urine flow

19. • Proteus – urease –NH4 – alkaline urine -
struvite stones
• Endotoxins of Gram negative – decreases
ureteral peristalsis
• Hemolysin – damage tubular epithelium –
promotes invasion
• Aerobactin of E.coli – promote iron
accumulation for bacterial replication

20. Risk factors for UTI
Reduced Urine Flow
outflow obstruction (BPH , carcinoma, urethral
stricture, foreign body, calculus)
neurogenic bladder
inadequate fluid uptake

21. Promote Colonization
sexual activity – increased inoculation
spermicide – increased binding
estrogen depletion – increased binding
antimicrobial agents – decreased indigenous flora

22. Facilitate Ascent
catheterization
urinary incontinence
fecal incontinence
residual urine with ischemia of bladder wall

23. TYPES OF UTI AND SOME
RELATED TERMS

24. Uncomplicated UTI
• OPD visit
• Non-pregnant female
• Anatomically and functionally normal urinary
tract

25. Complicated UTI
• Male
• Pregnant female
• Anatomic or functional abnormality of urinary
tract
• Immuno-compromised host
• Metabolic abnormality
• Instrumentation
• Multi-drug resistant bacteria

26. ASYMPTOMATIC BACTERIURIA
• Positive urine culture( Ucx >_10(5)CFU/ml ) in
the absence of infection
• Investigate and treat only in
Pregnant women
Renal transplant pts
About to undergo urinary tract procedures.

27. Acute uretheral syndrome
• Lower UTI symptoms and pyuria with < 10(5)
bacteria/ml urine
• mos- Chlaymdia trachomatis , ureaplasma
urealyticum , N.gonorrhoea
• If no specific etiology – empirical t/t with
doxycycline 1oo mg PO bd for 7 days or
azithromycin 1 g po single dose

28. Catheter asc. UTI
• Risk of bacteriuria is 5%/day , 25%/wk and
100%/month.
• 40% of nosocomial infections
• m/c source of gram negative bacteremia.
• Dx : 10(2) CFU/ml
• mo – E.coli , proteus , enterococcus ,
enterobactor , serratia ,pseudomonas ,
candida .

29. UTI in male
• At risk : older men with prostatic disease,
instrumentation ,anal sex
• Ucx : 10(3) CFU/ml ; sensitivity and specificity
97%

30. RECURRENT UTI
• 27% of young women
>_ 3 episodes/year
>_ 2 episodes/6 months
• Identify organism by culture
• RELAPSE : infection with same organism
• RECURENCE : infection with different
organisms

31. PREVENTION :
1. Frequent and complete voiding
2. Avoidance of spermicide and/or diaphragm
3. Immediate voiding after intercourse
4. Good hydration
5. Low dose antibiotic prophylaxis

32. Recommendations for recurent UTI
1. Urinalysis and midstream urine culture and
sensitivity should be performed with the first
presentation of symptoms in order to establish
a correct diagnosis of recurrent UTI
2. Patients with persistent hematuria or persistent
growth of bacteria aside from Escherichia coli
should undergo cystoscopy and imaging of the
upper urinary tract.
SOGC CLINICAL PRACTICE GUIDELINE 1088
NOVEMBER JOGC NOVEMBRE 2010

33. 3. Sexually active women suffering from
recurrent UTI and using spermicide should be
encouraged to consider an alternative form
of contraception.
4. Prophylaxis for recurrent UTI should not be
undertaken until a negative culture 1 to 2
weeks after treatment has confirmed
eradication of the urinary tract infection.

34. 5. Continuous daily antibiotic prophylaxis using
cotri- moxazole, nitrofurantoin, cephalexin,
trimethoprim, trimethoprim-sulfamethoxazole, or
a quinolone for recurrent UTI
6. Women with recurrent UTI associated with
sexual intercourse should be offered post-coital
prophylaxis as an alternative to continuous
therapy in order to minimize cost and side effects

35. 7. Acute self-treatment should be restricted
to compliant and motivated patients in
whom recurrent UTI have been clearly
documented.
8. Vaginal estrogen should be offered to
postmenopausal women who experience
recurrent UTI.
9. Cranberry products are effective in reducing
recurrent UTI.

36. 10. Acupuncture may be considered as an
alternative in the prevention of recurrent UTI in
women who are unresponsive to or intolerant
of antibiotic prophylaxis.
11. Probiotics and vaccines are of no proven
therapy for recurrent UTI
12. Pregnant women at risk of recurrent UTI
should be offered continuous or post-coital
prophylaxis with nitrofurantoin or cephalexin,
except during the last 4 weeks of pregnancy

37. Acute prostatitis
• Fever with chills, dysuria, and a boggy, tender
prostate on examination
• Diagnosis - physical exam and urine Gram
stain and culture.
• Enteric gram negatives are the usual causative
organism

38. Chronic prostatitis
• low back pain, perineal, testicular, or penile
pain, dysuria, ejaculatory pain, recurrent UTIs
with the same organism, or hematospermia
• frequently abacterial
• Dx- quantitative urine cultures before and
after prostatic massage
• TRUS if abscess suspected.

39. Acute epididymitis
• unilateral scrotal ache with swollen and
tender epididymis on exam
• Causative org.
- N. gonorrhoeae or C. trachomatis in sexually
active young men
- gram-negative enteric organisms in older men

40. PYELONEPHRITIS
• Fever with chills and rigors
• N/V , diarrhoea ,tachycardia
• CV or renal angle tenderness
• Leucocytosis
• Urine microscopy : pyuria + WBC casts +
hematuria
• Gram negative sepsis

41. COMPLICATION :
1. Sepsis
2. Papillary necrosis
3. Abscess
4. Ureteral obstruction
5. Impaired function if scarring
6. Pregnany – preterm labour

42. • Rapid increase in Sr. Creatine may indicate
PAPILLARY NECROSIS ( sickle cell ds , DM,
analgesic nephropathy )
• INTRAPARENCHYML ABSCESS s/b suspected
when pt has continued fever and bacteremia
despite antibiotic therapy .

43. EMPHYSEMATOUS PYELONEPHRITIS
• Severe acute necrotizing parenchymal renal
infection caused by gas-forming bacteria.
• Much higher mortality .
• No specific symptoms and signs, and can be
present in the absence of a septic physiology.

44. • EPN should be suspected in patients who are
not responding to therapy
 unexplained abnormal gas formation in the
body, especially in diabetic patients with poor
glycemic control.
• High-dose antibiotic therapy alone or with
percutaneous drainage in contrast to bilateral
nephrectomy may be a preferable approach to
salvage kidney function

46. EPN classification by Huang and Tseng
Class Description
Class I Gas in collecting system only
Class II Parenchymal gas only
Class III a Extension into perinephric tissue
Class III b Extension into pararenal space
Class IV EPN in solitary kidney , or bilateral
disease

47. XANTHOGRANULOMATOUS
PYELONEPHRITIS
• Chronic pyelonephritis
• Defect in microbial processing
• Deposition of lipid laden macrophages
• Middle aged women with recurrent UTI
• Mo : E.coli , proteus , kliebsella ,
pseudomonas , E. fecalis
• t/t : iv antibiotics , partial/total neprectomy
• Consider RCC

48. Xanthogranulomatous pyelonephritis

50. DIAGNOSIS OF UTI
 History
 Physical examination
 Urine-analysis
 Imaging

52. Clinical symptoms of UTI
• CYSTITIS - dysuria ,urgency , frequency ,
suprapubic pain , cloudy urine , strangury
• PYELONEPHRITIS – fever with chills , N/V ,
flank pain , CV tenderness
• UROSEPSIS – + shock

53. Physical Exam:
CVA tenderness ( pyelonephritis )
Urethral discharge ( urethritis)
Tender prostate on DRE ( prostatitis)

54. Urinalysis
 Leukocyte esterase
 Nitrites
More likely gram-negative rods
 WBCs ( >_ 10 /HPF )
 RBCs ( stones , obstructive lesions ,
mallignancy )
 C/S

55. Collecting urine sample
• MSU
• Samples from urinary bags and bed-pans
should not be used
• Suprapubic puncture – most reliable
• Urine in bladder > 4 hrs

57. Dx-Interpretation
Urine culture
10(5) CFU/ml – standard
10(3) -10(4) significant if symptomatic
Several strains – likely contamination

58. Indications for Radiologic Imaging
with UTI
• non responsive to treatment
• with predisposing factors
• Imaging modalities
X-ray KUB
USG abdomen and pelvis
Non-contrast CT abdomen and pelvis
Cystoscopic or ureteroscopic evaluation of the
urinary tract (rarely )

60. DIAGNOSTIC
FLOWCHART FOR UTI

63. Differential diagnosis
• Herpes genitalis (HSV)
• N. Gonorrhoeae
• Chlamydia
• Trichomonas
• Vaginitis
• Prostatitis
• Nephrolithiasis
• Trauma
• Urinary tract tuberculosis
• Urinary tract neoplasm
• Intra-abdominal abscess
• Sepsis – source other than GU system
• Overactive bladder

64. MANAGEMENT
• Principles of management :
hydration
 relief of urinary tract obstruction
 removal of foreign body or catheter if feasible
correctable cause of GU abnormalities and
metabolic abnormality
 judicious use of antibiotics

66. ANTIBIOTICS
• Highest mean urine concentration (from
highest to lowest):
Cabrenicillin > Cephalexin > Ampicillin >
TMP/SMX > Cipro > Nitrofurantoin

67. Uncomplicated UTI (cystitis, some pyelonephritis)
Nitrofuratoin 100 mg BID x 5 days or a 3 day
course of oral TMP/SMX - 95% effective
If TMP/SMX resistance is > 10 – 20% - consider
fluoroquinolones.
Only use fluoroquinolones or beta-lactams if one
of these recommended antibiotics cannot be
used due to availability, allergy, or tolerance

68. Other Uncomplicated UTI
7 – 10 day antibiotic course
 diabetes
 symptom duration before treatment of > 7 days
pregnancy
 age >65 years
past history of pyelonephritis
 UTI with resistant organisms

72. Antibiotic therapy for recurrent UTI

73. REFERENCES
• Davidson’s Principles and Practice of Medicine
22E
• Harrison’s Principles of Internal Medicine 19E
• THE WASHINGTON MANUAL OF MEDICAL
THERAPEUTICS 34E
• American society of urology 2016