DM complications Flashcards
Diabetic Neuropathy risk factors
Glucose control
Duration of diabetes
Damage to blood vessels
Mechanical injury to nerves: compression
Autoimmune factors: inflammation of nerves
Genetic susceptibility
Smoking
Diet
Pathogenesis of Diabetic Neuropathy
- Linked to duration of diabetes and level of glucose control
- May affect any part of the nervous system: cranial, peripheral, and autonomic
- MC: lower limbs
- Nerve fiber repair mechanisms: impaired in DM
- Nerve ischemia, or reduced nerve blood flow
metabolic factors: - High blood glucose
- Advanced glycation end products
- Sorbitol
- Abnormal blood fat levels
Signs of autonomic neuropathy
orthostatic hypotension
resting tachycardia
evidence of peripheral dryness or cracking of skin.
screening diabetic neuropathy
Type 2:
- at dx
Type 1: 5 yrs after dx
-annually thereafter
Comprehensive foot exam
- skin integrity (calluses and sores, especially between toes)
Skin sensation: - temperature/pinprick = small fibers
- vibration with 128 Hz tuning fork = large fibers
Quantitative sensorytesting
Monofilaments [10g]: checks for loss of sensation -> ulceration + amputation risk - Nerve conduction studies can detect possible nerve damage by assessing the transmission of nerve impulses
- ultrasound of internal organs such as the bladder can assist in determining if there is any abnormal function or structure to the organ
check annually or at every visit with neuropathy
Treatment of pain: diabetic neuropathy
- Gabapentinoids
- serotonin-norepinephrine reuptake inhibitor
- tricyclic antidepressants
- sodium channel blockers
Symmetric Polyneuropathy
MC!!
“stocking -glove sensory loss”:
- affects distal toes/feet and moves up to calf or begins in hand
Sx:
- pain
- parastesia
- loss of vibratory sensation
- (Thermal sensation)
Amputation - Risk factors
Peripheral neuropathy with loss of protective sensation
Altered biomechanics (with neuropathy)
Evidence of increased pressure (callus)
Peripheral vascular disease
History of ulcers or amputation
Severe nail pathology
Charcot’s Foot
initial stage: acutely swollen foot with negative radiographic changes
Tx:
- appropriate rest
- elevation/immobilization
- refer to professional
daily foot examinations by the patient.
Patients should check for dry, cracking skin, calluses, and signs of infection between the toes and around the toenail.
Treatment of Symmetric Polyneuropathy
Glucose control
Pain control
- Tricyclic antidepressants
- Topical creams
- Anticonvulsants
Foot care: Screening and referral to a podiatrist
Usual locations of ulcers in the diabetic foot.
- dorsal portion of the toes
- plantar aspect of the metatarsal heads
- heel
Nylon monofilament test
10 gauge nylon monofilament pressed in 10 spots -> pt says yes every time they feel it
- 4/10 = loss of protective sensation
Peripheral Autonomic Dysfunction sx
- Neuropathic arthropathy (Charcot foot)
- Aching, pulsation, tightness, cramping, dry skin, pruritus, edema, sweating abnormalities
- Weakening of the bones in the foot leading to fractures
Peripheral Autonomic Dysfunction testing
Direct microelectrode recording of postglanglionic C fibers
Galvanic skin responses:
- measure the presence of sympathetic innervation in hands and feet
Measurement of vascular responses:
- Constriction of the blood vessels to heat = vascular denervation
