Bone/joint infections

Question 1

What is the difference between acute and chronic osteomyelitis?

Answer 1

acute=onset is days-1 week; symptomatic in 4 weeks w/out treatment or recurrence

Question 2

What are the THREE portals of entry for osteomyelitis?

Answer 2

1. hematogenous (20%)
2. contiguous (50%)
3. vascular insufficiency (30%)

Question 3

Infection spread through the blood stream; usually in children (<16 yrs old)

Answer 3

hematogenous entry

Question 4

Infection spread from adjoining soft tissue infection, surgical, or traumatic intro of bacteria to bone. Most commonly in those >50 yrs old. Polymicrobial usually

Answer 4

contiguous entry

Question 5

This type of entry is very difficult to treat, usually have underlying disease (DM, atherosclerosis, diabetic foot ulcers)

Answer 5

vascular insufficiency

Question 6

What is the empiric therapy for hematogenous infections for neonates, children, adults, IV drug users, and sickle cell disease?

Answer 6

neonates: nafcillin
children: nafcillin+cefotaxime (unvaccinated OR <5 yrs old)
adults: nafcillin

IV drug users: vancomycin+antipseudomonal

sickle-cell disease: nafcillin+cefotaxime or ceftriaxone

Question 7

What are the common pathogens in hematogenous osteomyelitis for:
neonates
children
adults
IV drug users
sickle-cell disease

Answer 7

neonates: S aureus, GNB
children: S aureus (+/- H. influenza)
adults: S aureus, GNB
IV drug users: pseudomonas, MRSA, GNB
sickle-cell disease: salmonella, S aureus

Question 8

What is the empiric therapy for contiguous AND vascular insufficiency osteomyelitis infections (THEY ARE THE SAME)? specifically, what is an example of single-drug regimen AND combination drug regimen?

Answer 8

single drug regimen:
zosyn

combination drug regimen: cefepime+metronidazole+vancomycin

Question 9

What is the DoT for osteomyelitis?

Answer 9

4-6 weeks

Question 10

Likely pathogen(s) for infective arthritis for adolescents/adults with possible STD contact?

What would you use to treat this population?

Answer 10

neisseria gonnorhea

ceftriaxone OR cefotaxime

Question 11

Likely pathogen(s) for infective arthritis for adults with NO possible STD contact?

How would you treat this population?

Answer 11

S. aureus, strep, enterobacteriaceae

Nafcillin+levofloxacin

Question 12

Likely pathogen(s) for infective arthritis for prosthetic joint/post-surgery?

How would you treat this population?

Answer 12

MRSA, pseudomonas

Vancomycin+anti-pseudomonal agent

Question 13

Likely pathogen(s) for infective arthritis for IV drug users?

How would you treat this population?

Answer 13

MRSA, pseudomonas

Vancomycin+anti-pseudomonal agent

Question 14

What is the DoT for non-gonnococcal (including MRSA) and gonococcal?

Answer 14

non-gonococcal=2-3 weeks; MRSA=3-4 weeks

gonococcal=7-10 days