Diabetic Foot Infections

Question 1

Why are diabetics at higher risk for foot infections?

Answer 1

peripheral arterial disease (poor blood flow), sensory and motor neuropathy (can’t feel)

Question 2

What are the common organisms for foot ulcers?

Answer 2

Staph (including MRSA), strep, enterobacteria, pseudomonas, obligate anaerobes.
More than one can be involved –> “polymicrobial”

Question 3

How are diabetic foot infections classified?

Answer 3

PEDIS Grade

Question 4

Clinical manifestations of PEDIS Grade 1

Answer 4

no s/s of infection = uninfected

Question 5

Clinical manifestations of PEDIS Grade 2

Answer 5

2+ signs of infection in skin and subcutaneous tissue = mild

Question 6

Clinical manifestations of PEDIS Grade 3

Answer 6

local infection involving deeper structures (abcess, osteomyelitis, fascitis, etc) = moderate

Question 7

Clinical manifestations of PEDIS Grade 4

Answer 7

local infection plus 2 or more of the following:
temp > 38 or 90
RR > 20 or PaCO2 12,000 or < 4,000
= severe

Question 8

Questions to ask before selecting antibiotic?

Answer 8

1. Is there a high risk of MRSA? (if so, include anti-MRSA if high risk or severe infection)
2. Has the patient received abx in last month? (if so, add gr- coverage)
3. Are there risk factors for pseudomonas? (if so, add anti-pseudo agent)
4. What is the infection severity status?

Question 9

Diabetic foot infection - General approach to treatment (soft tissue only)

Answer 9

mild - topical or oral (1-2 wks), outpatient
mod - oral or initial IV (1-3 wks), outpatient or inpatient
severe - inpatient, initial IV then oral, 2-4 wks

Question 10

Diabetic foot infection - General approach to treatment (bone or joint involvement)

Answer 10

All inpatient
can be IV or oral, for more severe initial IV then oral
few days (post amputation) or several months if residual dead bone postop

Question 11

Diabetic foot infection (mild) - MSSA or strep

Answer 11

DACC
Dicloxacillin
Amoxicillin-clavulanate (+anaerobes)
Clindamycin (some MRSA)
Cephalexin (no gr-)

Question 12

Diabetic foot infection (mild) - MRSA

Answer 12

Doxycycline (no strep)

Trimethoprim/SMX (? Strep)

Question 13

Diabetic foot infection (moderate) - MSSA, strep, entero, anaerobes

Answer 13

TIMELACC
Tigecycline
Imipenem (broad + pseudo)
Moxifloxacin
Ertapenem (broad no pseudo)
Levofloxacin
Ampicillin-clavulanate (no pseudo)
Cefoxitin (+ anaerobes)
Ceftriaxone

Question 14

Diabetic foot infection (moderate) - MRSA

Answer 14

Linezolid
Daptomycin
Vancomycin

Question 15

Diabetic foot infection (moderate) - pseudo

Answer 15

Piperacillin-tazobactam

Question 16

Diabetic foot infection (moderate) - MRSA, pseudo, entero and anaerobes

Answer 16

VAPCCC
Vancomycin
Aztreonam (add an anaerobe)
Piperacillin-tazobactam
Ceftriazine (add an anaerobe)
Cefepime (add an anaerobe)
Carbapenem