DIABETIC FOOT ULCER AND SOFT TISSUE INFECTIONS

1. DIABETIC FOOT ULCER AND SOFT
TISSUE INFECTIONS

2. DIABETIC FOOT ULCER
• Definition:
-can be defined as a group of syndromes in which neuropathy, ischemia, and infection lead to
tissue breakdown or ulceration possibly resulting in amputation
-Ulceration in diabetic foot due to lack of protective sensation
• Epidemiology
– incidence
• approximately 12% of diabetics have foot ulcers
• foot ulcers ; responsible- ~85% of lower extremity amputations
– risk factors
• factors associated with decreased healing potential
– uncontrolled hyperglycemia (Hb A1C > 8.0)
– inability to offload the affected area
– poor circulation
– infection
– poor nutrition
• factors associated with increased healing potential

3. Neuropathy
Peripheral
Vascular
Disease
Abnormal Foot
Pressures
Trauma
Foot Deformity
Limited Joint
Mobility
Previous
Ulceration
/Amputation
Old Age
Duration of Diabetes
Risk Factors

4. • neuropathy
– largest effect on diabetic foot pathology
– sensory dysfunction leads to lack of protective sensation
and is primary risk factor for ulcer development
– autonomic dysfunction leads to drying of skin due to lack
of normal glandular function
• angiopathy
– lesser effect than neuropathy
– >60% of diabetic ulcers have decreased blood flow due to
peripheral vascular disease
Pathophysiology

5. Wagner’s
University of texas
Classifications

7. Stages
Stage A: No infection or
ischemia
Stage B: Infection
present
Stage C: Ischemia
present
Stage D: Infection and
ischemia present
Grading
Grade 0:
Epithelialized wound
Grade 1: Superficial
wound
Grade 2: Wound
penetrates to
tendon or capsule
Grade 3: Wound
penetrates
to bone or
joint

8. • Symptoms
– often painless
• Physical exam
– depth of ulcer
• probe for bone
– presence of infection
• look for cellulitis, pus
• check for gangrene
– assess Achilles tendon tightness
• Silverskiöld test
– improved ankle dorsiflexion with knee flexed = gastrocnemius tightness
– equivalent ankle dorsiflexion with knee flexion and extension = Achilles tightness
– circulation
• assess dorsalis pedis and posterior tibialis pulses
Presentation

9. Work
up
Biochemical
• Fasting or random blood
sugar (FBS, RBS)
• Glycohemoglobin (HbA1C)
• Full blood count (FBC)
• Erythrocyte sedimentation
rates (ESR)
• CRP
• Wound and blood
cultures(C&S)
Imaging
Investigations
Vascular Assessment

10. • Plain radiograph of the foot
• AP,lateral, and oblique of foot and ankle
• MRI
• best for differentiating abscess from soft
tissue swelling
• Bone scan
•useful to differentiate between
•soft tissue infection
•osteomyelitis
•Charcot arthropathy
Imaging

11. Vascular
to evaluate the extent of occlusive vascular disease and in the
assessment of healing potential especially when clinical examination
suggests lower extremity ischaemia
• Doppler segmental artery pressures
• Ankle-brachial indices (ABI)
• Normal value 1.1, <0.9 abnormal
• Toe pressure measurements
• In general, 85%-100% of foot lesions will heal when toe pressures are
>40mmHg and less than 10% will heal if<20mmHg

12. General
– factors in deciding a treatment plan
• angiopathic vs. neuropathic
• deep vs. superficial
• +/- osteomyelitis, antibiotics based on bone biopsy culture sensitivities
• Nonoperative
– shoe modification
• indications
– prevention when signs of potential ulcers are present
• includes deep or wide shoes, custom insoles, rocker bottom soles, etc.
• of the available shoe only modifications, rocker sole shoes best reduce the plantar pressure on the forefoot
• medicare will cover modifications and custom shoes/insoles yearly
– wound care
• indications
– first line of treatment
• goals of wound care and dressings
– provide moist environment
– absorb exudate
– act as a barrier
– off-load pressure at ulcer
– total contact casting (TCC)
Investigations

13. Operative
• surgical debridement, antibiotics, contact casting +/- gastroc recession/TAL
– indications
• grade 3 or greater ulcers should undergo I&D with antibiotic treatment before casting
• ostectomy +/- TAL
– indications
• bony prominence causing internal pressure
– technique
• TAL indicated if tight Achilles
– several studies have shown TAL to be effective to help heal and prevent recurrence of plantar forefoot ulcers
• partial calcanectomy +/- TAL
– indications
• large heel ulcers with associated calcaneal osteomyelitis
– outcomes
• preserves limb length and decreases morbidity compared to higher level amputations
• Syme amputation
– indications
• forefoot gangrene and a palpable posterior tibial artery pulse

14. • Skin and soft-tissue infections (SSTIs)
are a common reason for presentation
to outpatient practices, emergency
rooms, and hospitals
SOFT TISSUE INFECTIONS

15. Erysi
pela
s
NF
Cellulitis
Cleveland Clinic Journal of Medicine-2012-RAJAN-57-66 5
Gas
gangrene

16. • Often caused by Group A β - haemolytic streptococci,
(Streptococcus pyogenes)
• The infected area is painful, hot and oedematous
• Non-raised skin lesions with indistinct margin, sometimes with
lymphangitis
• There is usually no localization of the infection or pus
formation
• May associate with insect bites, trauma or ill fitting shoes
• IV C Pen 2.4 Mu, IV Cloxacillin. Dressing with CHD cream
Cleveland Clinic Journal of Medicine-2012-RAJAN-57-66 8

17. INDICATIONS FOR ADMISSION:-
• Severe or rapidly worsening infection
• Patient systemically unwell
• Uncertainty regarding the diagnosis (need to out rule
DVT)
• Immunocompromised patient. Diabetes mellitus – if
unstable
•Children under one year of age or elderly without good
home support
Johnny Loughnane

18. • An aggressive subcutaneous infection that tracks along
the superficial fascia, which comprises all the tissues
between the skin and underlying muscles
18
• Rapid progression
• Physical exam
✓ Skin bullae
✓ Ischemic patches
✓ Swelling, edema
✓ Crepitus
Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections:
2014 Update by the Infectious Diseases Society of America

19. 19

20. • Features that suggest involvement of deeper tissues
include
(1) severe pain that seems disproportional to the clinical
findings; (2) failure to respond to initial antibiotic therapy;
(3)the hard, wooden feel of the subcutaneous tissue,
extending beyond the area of apparent skin involvement;
(4) systemic toxicity, often with altered mental status;
(5)edema or tenderness extending beyond the cutaneous
erythema;
(6) crepitus, indicating gas in the tissues;
(7) bullous lesions;
(8) skin necrosis or ecchymoses
13
Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections:
2014 Update by the Infectious Diseases Society of America

21. Anaya DA, Dellinger EP. Necrotizing soft-tissue infection :
diagnosis and management. ClinInfect Dis 2007; 44:705–710,
Oxford University Press.
21

22. 22

23. • Surgical debridement
• Antibiotic
1
Type 1 Type 2
Polymicrobial infection.
Immunocompromised.
Group A strep
Cloxacillin 2g IV q4-6h
PLUS
Metronidazole 500mg IV q8h
PLUS
Gentamicin1 5mg/kg IV q24h
Benzylpenicillin 2-4 mega units IV
q4h
PLUS
Clindamycin 600mg IV q8h
National_Antibiotic_Guideline_200
ALTERNATIVES:
3rd gen. Cephalosporins
PLUS
Metronidazole 500mg IV q8h
OR
β-lactam/β-lactamase inhibitors, e.g.
Ampicillin/Sulbactam 1.5g IV q8h
OR
Amoxycillin/Clavulanate 1.2g IV q8h
PLUS/MINUS
Gentamicin1 5mg/kg IV q24h
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