Diabetic Foot Flashcards
What does the term ‘diabetic foot complications’ refer to?
Encompasses the conditions of diabetic foot ulcer (i.e., a full-thickness epithelial defect below/distal to the ankle) and diabetic foot infections (i.e., any soft-tissue or bone infection occurring in the diabetic foot, including osteomyelitis).
What are the risk factors for diabetic foot complications?
- History of diabetes mellitus
- Sensory neuropathy
- Previous history of foot ulcer
- Previous history of partial foot (toe) amputation
- Charcot’s mid-foot deformity
- Chronic kidney disease
Briefly describe diabetic foot ulcers
A full-thickness epithelial defect that has been present for ≥2 weeks. Most occur in the forefoot, the portion of the foot distal to the tarsometatarsal (Lisfranc) joint.
Patients with Charcot’s arthropathy (mid-foot collapse) may develop ulcers in the mid-foot that are associated with structural abnormalities there.
Heel ulcers are often due to decubitus pressure in non-ambulatory patients debilitated by previous stroke.
Whats signs and symptoms would indicate an infection in diabetic foot complications?
The presence of fever, chills, malaise, or anorexia is suggestive of an infection.
How can a neuropathic and ischemic foot ulcer be differentiated?
- Neuropathic: warm, dry skin, foot pulses are palpable
- Ischemic: cool, pale foot with no palpable pulses
What type of arthropathy is the best descrption of a Charcot joint?
Neuropathic
What pulses should be assessed in diabetic foot complications?
- Dorsalid pedis
- Posterior tibial
What investigations should be ordered for diabetic foot complciations?
- FBC
- Glucose level
- X-ray
- Microbial culture
- Doppler ultrasound
- Angiography
Why investigate FBC? And what may this show?
- Ordered in all patients with diabetic foot complications. May suggest the presence of an infection; however, test has poor sensitivity.
- May show leukocytosis with left-shift.
Why investigate blood glucose level? And what may this show?
- Ordered in all patients with diabetic foot complications. Often elevated in the presence of infection.
- May be elevated.
Why investigate using x-ray? And what may this show?
- Ordered in all patients with diabetic foot complications to screen for osteomyelitis, fractures, joint stability, and other deformities.
- May show hypolucencies, cortical destruction/osteolysis and/or joint subluxation.
Why investigate using microbial culture? And what may this show?
- If a diabetic foot infection is suspected, soft tissue or bone samples from the base of the wound can be sent for microbiological evaluation. If this is not possible, a deep swab can be taken as it may provide useful information on the choice of antibiotic treatment.
- Positive for causative organism in infection.
Why investigate using doppler ultrasound? And what may this show?
- Used to assess the peripheral arterial
circulation and determine the extent of vasculopathy - Reduced peripheral arterial circulation
Why investigate using angiography? And what may this show?
- Considered to be the best test for diagnosing peripheral artery disease.
- Haemodynamically significant (i.e., >50%) stenosis or occlusions between the aorta and the foot (if peripheral artery disease present).
What organisms can commonly cause diabetic foot infections?
- Staphylococcus aureus
- Beta-hemolytic streptococci
- Pseudomonas aeruginosa