E3- UTIs

Question 1

How are UTIs dx?

Answer 1

• Gram stain
• Culture (EMB/CLED)
• UA
• Prostate exam
• +/- imagaing

Question 2

What type of culture media is selective for gram negative organisms?

Answer 2

EMB

Question 3

What type of culture media is not selective for either gram positive or gram negative, but is used to determine the organisms ability to ferment lactose?

Answer 3

CLED

Question 4

What type of culture medias should be used to dx UTIs?

Answer 4

EMB/CLED

Question 5

What findings on UA microscopy are consistent with a UTI?

Answer 5

> 2 WBC or 15 bacteria

Question 6

Who might require imaging to dx a UTI?

Answer 6

• Children
• Adults with recurrent infections
• Pts with blood in their urine

Question 7

What are the 7 causative agents of UTIs?

Answer 7

• E. coili
• Klebsiella spp
• Proteus spp
• Enterococcus spp
• Staphylococcus saprophyticus
• Streptococcus agalactiae
• Pseudomonas aeruginosa

Question 8

What are the gram negative causative agents of UTIs?

Answer 8

-E. coili
-Klebsiella spp
-Proteus spp
-Pseudomonas aeruginosa
“Every Kid Pees Pants”

Question 9

What are the gram positive causative agents of UTIs?

Answer 9

-Enterococcus spp
-Staphylococcus saprophyticus
-Streptococcus agalactiae (GBS)
“Especially Slutty Girls”

Question 10

What is the most common cause of UTIs?

Answer 10

E. coli

Question 11

Is E. coli gram positive or gram negative? What shape?

Answer 11

Gram negative bacillus

Question 12

What stain of E. coli causes UTIs?

Answer 12

UPEC strains

Question 13

What is the lifecycle of E. coli?

Answer 13

• Access urinary tract following introduction of fecal contamination
• Use P fimbriae and Dr adhesions to bind to uroepithelial cells and erythrocytes
• Produce alpha and beta hemolysins
• Result in lysis of the uroepithelial cells and erythrocytes

Question 14

UPEC have the ability to produce what?

Answer 14

K (capsular) antigen

Question 15

Is Proteus gram positive or negative? What shape?

Answer 15

Gram negative bacillus

Question 16

What species of Proteus is commonly community acquired?

Answer 16

Proteus mirabilis

Question 17

What species of Proteus predominantly infects immunocompromised patients?

Answer 17

Proteus vulgaris

Question 18

What is seen on agar with Proteus infections?

Answer 18

“Swarming” (except on CLED agar)

Question 19

What structure do Proteus have that promote the attachment of bacteria to uroepithelial cells?

Answer 19

Fimbriae

Question 20

What does Proteus produce that makes the urine more alkaline? How?

Answer 20

Urease

Hydrolyzes urea to ammonia

Question 21

What can the increased pH caused by Proteus lead to?

Answer 21

Struvite stones

Question 22

Is Straphlococcus saprophyticus gram positive/negative? What shape?

Answer 22

Gram positive cocci

Question 23

Is Straphlococcus saprophyticus coagulase positive/negative?

Answer 23

Coagulase negative

Question 24

What organism is associated with “honeymoon cystitis”

Answer 24

Straphlococcus saprophyticus

Question 25

When do most cases Straphlococcus saprophyticus occur?

Answer 25

24 hours after sex

“honeymoon cystitis”

Question 26

How can you differentiate Straphlococcus saprophyticus from other coagulase negative staphs?

Answer 26

Based on its novobiocin resistance

Question 27

Is Streptococcus agalactiae gram positive/negative? What shape?

Answer 27

Gram positive cocci

Question 28

What is seen on culture with Streptococcus agalactiae?

Answer 28

Gray/white colonies with narrow zone of beta-hemolysis

Question 29

How do neonates get a Streptococcus agalactiae UTI?

Answer 29

Streptococcus agalactiae colonies the vaginia and can be passed during delivery

Question 30

What are the virulence factors of Streptococcus agalactiae? (4)

Answer 30

• Capsular polysaccharide
• Hyaluronidase
• Collagenase
• Hemolysin

Question 31

How is Streptococcus agalactiae dx?

Answer 31

• Detection of CAMP factor

- Definitive dx requires isolation from urine, blood, or CSF