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Flashcards in Microbiology : UTI Deck (81)
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1
Q

Who is more at risk for UTI: Young Man or Elderly Female ?

A

Elderly Female . Much more

Females > Males
Elderly > Young, Adults

Old Woman = A walking UTI machine.

2
Q

Which is the more common way for bacteria to get into the kidney: Ascending UTI Infection or hematogenous spread ?

A

Ascending UTI (Urethra –> Bladder–> Ureters –> Kidney)

3
Q

What doe most renal infections seeding from bacteremia produce ?

A

Abscess !

Infection is usually seen in the parenchyma

4
Q

What are common causes of Ascending UTI’s ?

A

Sexual Intercourse (Staph Saprophyticus)
Fecal Incontinence
Urinary Catheters (Staph epidermidis)
Retrograde Urine flow

5
Q

Which local factors would render a person more susceptible to UTI ?

A
Physiological obstruction
   Infrequent voiding
   Neurogenic or Neuropathic bladder
   Detrusor muscle instability
Congenital abnormality
   Retrograde urine flow 
Catheter
Instrumentation
Trauma
Malnutrition
Diabetes
Hyperosmolality 
IC
Tolerance to pathogen (cross-reactivity of host)
6
Q

What is vesicoureteral reflux ?

A

Urine from the bladder flows retrograde back into the ureters and causes a backup of in the kidney. This flow of urine can lead to seeding of bladder infection into the kidneys .

Another variant is urethravesicular flow (urine flows from urethra into the bladder )

7
Q

How does hyperosmolarity predispose someone for UTIs ?

A

Inhibits PMN migration to damaged tissue

8
Q

Describe the inherent anti-microbial (UTI protection) in humans

A
Antibacterial activity of urine :
    low pH; high organic acids 
    high urea concentration
    high urine osmolality
    Low vaginal pH
Flushing mechanism of bladder
Peristaltic movement of ureters 
Estrogen (young women)
Anti-adherence effect of uromucoid
Local secretion of immunoglobulins (IgA)
Antibacterial activity of prostate secretions of post-pubescent males
Long urethra in males
9
Q

What do indwelling catheters form that lead to UTI susceptibility ?

A

A nidus.

Allows for bacterial colonization

10
Q

What common disease state in older males may lead to UTI ?

A

Prostatic hyperplasia

11
Q

What is the most important factor that allows for bacterial colonization in the urinary tract ?

A

ADHESION !

Adhesion determines the extent of bacterial colonization

12
Q

What is adherence specificity >

A

The type of adhesion molecules determines where in the urinary tract a bacteria can colonize

13
Q

p-Fimbrae and Pilli are bacterial constituents that allow for …

A

adhesion !

Mutant fimbrae –> decreased pathogenicty

Maternal ab’s protect against pFimbrae

14
Q

Define K-antigens

A

capsular acidic polysaccharides that show resistance to bactericidal action of Ig and complement … mainly anti-phagocytic.

15
Q

What is the most important adhesion molecule made by UTI causing E.coli ?

A

p-Fimbrae

16
Q

Besides reflux, what allows for the ability to ascend in the GU system ?

A

Intrinsic motility of the organism

17
Q

Where in the GU is Acute Cystitis often seen ?

A

Lower (bladder)

Typically a superficial infection

18
Q

What demographic often gets Acute Cystitis ?

A

Young Women

19
Q

Do individuals who get Acute Cystitis, often have physiologic or anatomical aberrations that lead to the infection ?

A

NOPE…

However, residual bladder urine is associated with it

20
Q

What are common signs of acute cystitis ?

A
Frequent urination (urgency)
Lower abdominal discomfort
BURNING PAIN and Feeling of FULLNESS

May see hematuria but not always

21
Q

Where is inflammation seen in Tuberointerstitial disease ?

A

Kidney parenchyma and renal pelvis.

22
Q

What will be seen on the kidney in uberointerstitial disease ?

A

Small abscesses

23
Q

What are common symptoms associated with uberointerstitial disease ?

A

Fever and back pain (may see renal dysfunction)

24
Q

Describe the clinical onset of Acute Pyelonephritis

A

Abrupt onset
Chills, fever, headache, back pain
Tenderness over costovertebral angle

25
Q

bladder irritation in Acute Pyelonephritis will lead to …

A

dysuria, frequency and urgency.

26
Q

Proteus mirabilis invlovement in Acute pyelonephritis causes what to occur ?

A

Magnesium ammonium stones

27
Q

What occurs to the renal pelvis in Chronic Pyelonephritis ?

A

Scarring and deformation of pelvis

28
Q

Is chronic pyelonephritis a cause of renal failure ?

A

YES !

29
Q

Loss of tubular function in Chronic Pyelonephritis leads to

A

Polyuria
Nocturia
Mild proteinuria

30
Q

Acute Urethral Sndrome occurs in 50% of women who also show …

A

Dysuria and frequency

31
Q

Acute urethral Syndrome usually always presents with …..

A

Acute Cystitis

32
Q

What infections typically present like Acute Urethral Syndrome ?

A

Chlamydia and Herpes

33
Q

What percentage of pregnancies result in an Upper RTI ?

A

33%

34
Q

What events in pregnancy predispose women to UTI ?

A

Estrogen and progesterone induced dilation of uterus, bladder, pelvis

increased bladder capacity

decreased ureteral peristalsis

vesicoureteral reflux

35
Q

Who typically gets Complicated UTI (Cystitis and Pyelonephritis ) ?

A

Pre-menstral girla
Post-menopausal women

HOWEVER, if a man gets a UTI its is most likely going to be COMPLICATED

36
Q

What percentage of nosocomial infections are catheter related ?

A

35-40%

Most asymptomatic

Greater risk in women

37
Q

What class of bacteria are most commonly seen in catheter associated bacteremia ?

A

Gram -‘s

CATHETER ASSOCIATED BACTERIMIA IS MOST COMMONLY ASSOCIATED WITH CATHETER USE !

38
Q

List the most common causative agents of G - UTI

A
Enterobacters
    E.coli
    Proteus mirabilis
    Morganell morganii
    Kleb pneumo
Psedomonas aeruginosa
Mycoplasma
39
Q

What are the most common forms of G + bacteria associated with UTI ?

A

Staph. saprophyticu
Staph epidermidis

Less common: Staph aureus, Clostridium

40
Q

What is the most common yeast associated with UTI

A

candida

41
Q

What is the most common pathogen seen in UTI ?

A

E.coli (90% of acute bacterial cystitis)
80% community
30-50% nosocomial UTI’s

42
Q

K Antigens associated with E.cloi ?

A

O1, O2, O4, O6, O7, O75

43
Q

E.coli K groups associated with Children ?

A

11, 24, 36, 37

44
Q

What type of Pilli do all serotypes of E.coli have ?

A

Type I

45
Q

What does Type I pilli bind to in order to adhere ?

A

Mannose Receptors

46
Q

Strains that causes cystitis have a higher affinity for what than fecal strains ?

A

uroepithelial cells

47
Q

Describe the symptoms seen in HUS caused by EHEC

A

Acute Renal Failure
Microangiopic Hemolytic Anemia
Thrombocytopenia

48
Q

HUS due to EHEC is seen in what age group predominantly ?

A

Children under 10 years of age

49
Q

What foods often contain EHEC ?

A

Contaminated (undercooked) beef
Unpasteurized milk
Fruit juices

50
Q

EHEC infection often presents with bloody diarrhea. What is the most common serotype of EHEC ? What will it not do on MacKonkey agar ?

A

O-157: H7

It will not ferment sorbitol !!

51
Q

What is phase variation ?

A

Although a bacteria has the potential to produce many different fimbrae with affinity for different body cavities, it usually will not produce all of them at once making the infection very specific for a certain type of fimbrae.

52
Q

E.coli is associated with which disease which causes entrapment of air within the kidney ?

A

Emphysematous pyelonephritis

53
Q

Who is most at risk for emphysematous pyelonephritis ?

A

Diabetics (especially women)

54
Q

What are the main treatment options for emphysematous pyelonephritis ?

A

Nephrectomy

Anti-bacterial

55
Q

Is Proteus mirabilis more associated with community acquired UTI or nosocomial ?

A

Nosocomial

56
Q

Proteus produces which kind of pilli ?

A

Type I

57
Q

Why is proteus’ ability to change its surface composition important ?

A

Allows it to adapt to conditions that may need a different attachment protein

Escape from phagocytosis

58
Q

What kind of motility does proteus have ?

A

SWARMING

59
Q

Proteus is urease + or - ?

A

+ !

60
Q

Salmonella can cause what condition, which is associated with sepsis ?

A

Bacteriuria (often seen in the elderly)

61
Q

Klebsiella: Nosocomial or CA UTI ?

A

Nosocomial

62
Q

Enterobacter:Nosocomial or CA UTI

A

Nosocomial

63
Q

Pseudomonas: Nosocomial or CA UTI

A

Nosocomial

64
Q

Psedomonas, like salmonella, is a cause of bacteriuria. Unrelated to this is the fact that it is Oxidase (+/-) ?

A

+ !

65
Q

Mycoplasma genitalium can be found in the healthy male urethra but also may be associated with which two infective states ?

A

Pelvic Inflammatory Disease

Non-gonnococal urethritis

66
Q

Ureaplasma urealyticum causes what complication in pregnancy ?

A

Chorioamniotis

Premature delivery

In addition :
frequently transmitted from mothers to their infants, causing
pneumonia,
persistent pulmonary hypertension,
chronic infection of the central nervous system and
bronchopulmonary dysplasia.

67
Q

What are the lab diagnostics for S.aureus

A

G+
Catalase +
Coagulase +
Non-Motile

68
Q

What deadly complication can be seen with S.aureus UTI ?

A

Bacteremia

69
Q

Lab diagnostics for S. saprophyticus

A

Gram +

Catalase and Coagulase -

70
Q

Who is most at risk for UTI due to S. saprophyticus

A

young sexually active women (Honeymoon Cystitis)

71
Q

Does Staph. epidermis typically cause infection in healthy adults ?

A

Nope, it is opportunistic

72
Q

Which pathogen(s) are commonly found in patients with diabetes ?

A

Clostridia

Yeasts: Candida Torulopsis glabrata

73
Q

Clostria, yeast and e.coli can often cause which disease that results from a direct UTI or a fistula from the GI tract connecting to the UT ?

A

Empysematous cystitis

74
Q

In addition to chemotherapy and radiation. Which three viruses are responsible for hemorrhagic cystitis ?

A
Adenovirus (Type 11, more selective for UT)
Varicella Zonster
BK polyoma (may also be indicated in bladder cancer)
75
Q

What are the four most common bacterial causes of prostatitis ?

A

E.coli
Proteus
Klebsiella
Enterococcus

76
Q

In urinary tuberculosis where will you see the first lesion in this infection ?

A

Kidney

May progress to gall bladder, prostate, seminal vesicles.

77
Q

How is TB spread to the UT ?

A

hematogenous spread

78
Q

In which patients do you often see Urinary TB

A

Older patients with latent TB

79
Q

In schistasomiasis, the eggs lead to what kind of reaction ?

A

granulomatous

80
Q

What other disease is associated with schistosomiasis ?

A

BLADDER CANCER

81
Q

What is the best way to diagnose UTI ?

A

Urine sample !

Use a hemocytometer on uncentrifuged urine

You can also gram stain centrifuged urine