Micro - Systems (Osteomyelitis, UTIs, & Vaginal infections)

Question 1

What pathogen should be assumed as cause of osteomyelitis if no other information is available, and why?

Answer 1

S. aureus (most common overall)

Question 2

What pathogen is a likely cause of osteomyelitis if the patient is sexually active, and why?

Answer 2

Neisseria gonorrhoeae (rare), septic arthritis more common

Question 3

What 2 pathogens are a likely cause of osteomyelitis if the patient is a diabetic and/or IV drug user?

Answer 3

(1) Pseudomonas aeruginosa (2) Serratia

Question 4

What pathogen is a likely cause of osteomyelitis if the patient has sickle cell?

Answer 4

Salmonella

Question 5

What 2 pathogens are a likely cause of osteomyelitis if the patient has history of a prosthetic joint replacement?

Answer 5

(1) S. aureus (2) S. epidermidis

Question 6

What pathogen is a likely cause of osteomyelitis if the patient has vertebral involvement? What is this condition called?

Answer 6

Mycobacterium tubuerculosis (Pott disease)

Question 7

What pathogen is a likely cause of osteomyelitis if the patient has a history of cat and/or dog bites?

Answer 7

Pasteurella multocida

Question 8

In what patient population does most osteomyelitis occur?

Answer 8

Most osteomyelitis occurs in children

Question 9

What are 2 nonspecific findings that may be observed with osteomyelitis?

Answer 9

Elevated CRP and ESR observed but nonspecific

Question 10

What are the imaging considerations/options regarding osteomyelitis?

Answer 10

Can be subtle on radiographs; same lesion more easily seen on MRI

Question 11

What are 5 components of the presentation of cystitis?

Answer 11

Cystitis presents with (1) dysuria (2) frequency (3) urgency (4) suprapubic pain (5) WBCs (but not WBC casts) in urine

Question 12

What is the primary cause of cystitis?

Answer 12

Primarily caused by ascension of microbes from urethra to bladder

Question 13

What are 2 causes of and/or contexts for cystitis in males?

Answer 13

Males - (1) Infants with congenital defects (2) Vesicoureteral reflux

Question 14

What is a cause of and/or context for cystitis in elderly?

Answer 14

Elderly - enlarged prostsate

Question 15

What is the primary cause of pyelonephritis?

Answer 15

Ascension (of microbes from urethra) to kidney results in peylonephritis

Question 16

What are 6 components of the presentation of pyelonephritis?

Answer 16

Presents with (1) fever (2) chills (3) flank pain (4) costovertebral angle tenderness (5) hematuria (6) WBC casts

Question 17

In which patient population are urinary tract infections more common, and why? How much more common are they in this patient population?

Answer 17

Ten times more common in women (shorter urethras colonized by fecal flora)

Question 18

Besides female gender, what are 6 other factors that predispose patients to urinary tract infections?

Answer 18

Other predisposing factors include: (1) obstruction (2) kidney surgery (3) catheterization (4) GU malformation (5) diabetes (6) pregnancy

Question 19

What diagnostic marker is positive in bacterial UTI? What diagnostic marker is positive for gram-negative bacterial UTI?

Answer 19

Diagnostic markers: leukocyte esterase test (+) = bacterial UTI; nitrite test (+) = gram-negative bacterial UTI

Question 20

What bug is the leading cause of UTI?

Answer 20

Escherichia coli

Question 21

Which agar distinguishes Escherichia coli, and how does it appear on this agar?

Answer 21

Colonies show green metallic sheen on EMB agar

Question 22

What is the second leading cause of UTI in sexually active women?

Answer 22

Staphylococcus saprophyticus

Question 23

What is the 3rd leading cause of UTI?

Answer 23

Klebsiella pneumoniae

Question 24

What distinguising product do some strains of serratia marcescens produce?

Answer 24

Some strains produce a red pigment

Question 25

Name 3 UTI bugs that are often/usually nosocomial and drug resistant.

Answer 25

(1) Serratia marcescens (2) Enterobacter cloacae (3) Pseudomonas aeruginosa

Question 26

In what unique fashion does Proteus mirabilis appear on agar, and why?

Answer 26

Motility causes "swarming" on agar

Question 27

Name a urease positive UTI bug.

Answer 27

Proteus mirabilis

Question 28

With kind of stones are associated with Proteus mirabilis?

Answer 28

Associated with struvite stones

Question 29

With what pigment and odor is Pseudomonas aeruginosa associated?

Answer 29

Blue-green pigment and fruity odor

Question 30

What do each of the following UTI diagnostic makers suggest if positive: (1) Leukocyte esterase (2) Nitrite test

Answer 30

(1) (+) Leukocyte esterase = bacterial (2) (+) Nitrite test = gram-negative bugs

Question 31

What UTI bugs would a positive versus negative test suggest?

Answer 31

(+) Urease test = urease-producing bugs (e.g., Proteus, Klebsiella); (-) Urease test = E. coli, Enterococcus

Question 32

What are 2 defining features of Klebsiella pneumoniae's appearance?

Answer 32

Large mucoid capsule and viscous colonies

Question 33

Name 3 common vaginal infections.

Answer 33

(1) Bacterial vaginosis (2) Trichomoniasis (3) Candida vulvovaginitis

Question 34

Of the following common vaginal infections, which is associated with inflammation: (1) Bacterial vaginosis (2) Trichomoniasis (3) Candida vulvovaginitis?

Answer 34

(1) No inflammation (2) Inflammation (3) Inflammation

Question 35

What are the defining signs and symptoms of bacterial vaginosis (in terms of inflammation and discharge)?

Answer 35

No inflammation; Thin, white discharge with fishy odor

Question 36

What are the defining signs and symptoms of Trichomoniasis (in terms of inflammation and discharge)?

Answer 36

Inflammation; Frothy, grey-green, foul-smelling discharge

Question 37

What are the defining signs and symptoms of Candida vulvovaginitis (in terms of inflammation and discharge)?

Answer 37

Inflammation; Thick, white "cottage cheese" discharge

Question 38

What are the lab findings that distinguish each of the following common vaginal infections: (1) Bacterial vaginosis (2) Trichomoniasis (3) Candida vulvovaginitis?

Answer 38

(1) Clue cells, pH > 4.5 (2) Mobile trichomonads, pH > 4.5 (3) Pseudohyphae, pH normal (4.0-4.5)

Question 39

What is the treatment for each of the following common vaginal infections: (1) Bacterial vaginosis (2) Trichomoniasis (3) Candida vulvovaginitis? In which condition is treatment of sexual partner recommended?

Answer 39

(1) Metronidazole (2) Metronidazole, Treat sexual partner (3) -azoles

Question 40

What is the pH in each of the following common vaginal infections: (1) Bacterial vaginosis (2) Trichomoniasis (3) Candida vulvovaginitis?

Answer 40

(1) pH > 4.5 (2) pH > 4.5 (3) pH normal (4.0-4.5)