Infectious Diseases Approach to the Diabetic Foot Cristina - - PowerPoint PPT Presentation

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Cristina Brickman, MD MSCE Assistant Clinical Professor of Medicine UCSF Division of Infectious Diseases April 8, 2017

Infectious Diseases Approach to the Diabetic Foot

Disclosures

• I have no disclosures

Overview

• Will focus on antibiotic selection

– General approach to antibiotics – Skin and soft tissue infections (SSTI) – Osteomyelitis

• Borrowing from 2012 IDSA Clinical Practice Guideline

for the Treatment and Diagnosis of Diabetic Foot Infections

General Approach to Antibiotics

Gram Positive Gram Negative

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General Approach to Antibiotics

Gram Positive Gram Negative

MRSA Pseudomonas

General Approach to Antibiotics

Gram Positive Gram Negative

MRSA Pseudomonas

• Do I need to cover MRSA?
• Do I need to cover Pseudomonas?
• Do I need to cover anaerobes?

Skin and Soft Tissue Infections: Mild

Gram Positive Gram Negative

MRSA Pseudomonas

• Mild-moderate infection: localized to skin & subcutaneous

tissue, mild cellulitis

• Gram positive coverage sufficient
• Pus or open wound = Staphylococcus aureus

– clindamycin, trimethoprim-sulfamethoxazole

• Non-purulent cellulitis = Group A Streptococcus

– 1st generation cephalosporin

• “Treat until better”

Skin and Soft Tissue Infections: Mild

Gram Positive Gram Negative

MRSA Pseudomonas

• Mild-moderate infection: localized to skin & subcutaneous

tissue, mild cellulitis

• Gram positive coverage sufficient
• Pus or open wound = Staphylococcus aureus

– clindamycin, trimethoprim-sulfamethoxazole

• Non-purulent cellulitis = Group A Streptococcus

– 1st generation cephalosporin

• “Treat until better”

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Skin and Soft Tissue Infections: Severe

Gram Positive Gram Negative

MRSA Pseudomonas

• Severe infection: extensive cellulitis, myositis,

necrotizing infections, systemic symptoms

• Polymicrobial

– Vancomycin (MRSA) – Anti-pseudomonal with anaerobic coverage

Skin and Soft Tissue Infections: Severe

Gram Positive Gram Negative

MRSA Pseudomonas

• Severe infection: extensive cellulitis, myositis,

necrotizing infections, systemic symptoms

• Polymicrobial

– Vancomycin (MRSA) – Anti-pseudomonal with anaerobic coverage Clostridia

Osteomyelitis

• Multidisciplinary approach
• No single recommended antibiotic regimen

– IV therapy common but not strictly required – Combination antibiotics often necessary

• Culture data extremely useful

– Help determine whether need MRSA or Pseudomonas coverage

• Optimal duration not well defined

Osteomyelitis: oral antibiotics

Gram Positive Gram Negative

MRSA Pseudomonas Clostridia

First Line Fluoroquinolones Metronidazole (anaerobes only) Trimethoprim-sulfamethoxazole Clindamycin Second Line Doxycycline Linezolid Amoxicillin-clavulanate

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Osteomyelitis Case (1)

• 71M with DM and R 2nd toe infection s/p

debridement with residual osteomyelitis

• Cultures: Klebsiella, E. coli
• My interpretation:

– No evidence of MRSA or Pseudomonas – Still want relatively broad-spectrum coverage

• Potential antibiotics:

– IV: ceftriaxone, ertapenem – Oral: trimethoprim-sulfamethoxazole, moxifloxacin

Osteomyelitis Case (2)

• 71M with DM and R 2nd toe infection s/p

debridement with residual osteomyelitis

• Cultures: MRSA, Klebsiella, E. coli
• My interpretation:

– Require broad-spectrum Gram positive and Gram negative coverage

• Potential antibiotics:

– IV: vancomycin + ceftriaxone or ertapenem – Oral: trimethoprim-sulfamethoxazole +/- moxifloxacin

Osteomyelitis Case (3)

• 71M with DM, CKD and R 2nd toe infection s/p

debridement with residual osteomyelitis

• Cultures: MRSA, Pseudomonas
• My interpretation:

– Needs broad-spectrum Gram positive and Gram negative coverage including Pseudomonas

• Potential antibiotics:

– IV: vancomycin + piperacillin-tazobactam – Oral: clindamycin + moxifloxacin

Summary

Diabetic foot infection Skin and soft tissue Osteomyelitis Mild-moderate Gram-positive coverage Severe Broad-spectrum coverage Consider oral therapy! Cultures to determine need for MRSA or Pseudomonas coverage

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Thank you!

• Cristina.brickman@ucsf@edu