Metabolic neuropathy - B12 + diabetes Flashcards by Hannah Nolan

Causes ofperipheral metabolic neuropathy

diabetes mellitus, hypoglycemia, uremia, hypothyroidism, hepatic failure, polycythemia, amyloidosis, acromegaly, porphyria, disorders of lipid/glycolipid metabolism, nutritional/vitamin deficiencies, and mitochondrial disorders, among others

How well did you know this?

Not at all

Perfectly

What fibres does diabetic neuropathy affect

Sesory A + C fibres

How well did you know this?

Not at all

Perfectly

What anaemia does B12 deficiency present with

Megaloblastic anaemia

How well did you know this?

Not at all

Perfectly

Who is at risk of B12 deficiency

Chronic malabsorption
History of gastric resections or bypass
Meds eg metformin and PPIs, antiepileptics

How well did you know this?

Not at all

Perfectly

What us B12 deficiency level

<148 = probable
148-258 = possuble

How well did you know this?

Not at all

Perfectly

What can still have if normal serum B12 levels

Pernicious anaemia

How well did you know this?

Not at all

Perfectly

InvestigationsB12 deficiency

FBC, blood smear, serum B12, reticulocyte count
ConsiderL
MMA
Homocysteine
holotrasncobalamin
Anti intrinsic factor antibody

How well did you know this?

Not at all

Perfectly

Treatment for B12 deficiency with neuro nvolvement

Hydroxocobalamin 1mg
IM on alternate days until no further umprovemetn
Then IM HCB 1mg IM every 2 moths

How well did you know this?

Not at all

Perfectly

Treatment of B12 deficiency no neuro involvement

hydroxocobalamin 1 mg intramuscularly three times a week for 2 weeks
Non diet = hydroxyco. ever 2-3 months IM for life
Diet - oral cyanocobalamin 50-150 micrograms daily between meals OR twice yearly hydroxocobalamin 1mg

How well did you know this?

Not at all

Perfectly

Foods high in vit B12

Eggs.
Foods which have been fortified with vitamin B12 (for example some soy products, and some breakfast cereals and breads) are good alternative sources to meat, eggs, and dairy products.
Meat.
Milk and other dairy products.
Salmon and cod.

How well did you know this?

Not at all

Perfectly

First line management for neuropathic pain

One of:
Amitryptilline
Duloxetine
Gabapentin
Pregabalin
Capsaicin cream - avoid/intolerant to oral treatment
Cant have two oral meds together
Short ocourse of tramadol while qiating for referral

How well did you know this?

Not at all

Perfectly

When refer to a specialist pain service

They have severe pain.
Their pain significantly limits their participation in daily activities (including self-care, general tasks and demands, interpersonal interactions and relationships, mobility, and sleeping).
The underlying health condition that is causing neuropathic pain has deteriorate

How well did you know this?

Not at all

Perfectly

Features of SACD

Spasticity and up going plantars = UMN
Reduce proprioception and vibration sense - dorsal column
Normal sensation and fine touch
Bilateral symmetical lower limbs - spinal

How well did you know this?

Not at all

Perfectly

Wha tracts are affeted in SACD

lateral corticospinal tract (motor) and dorsal columns (proprioception and vibration) - highly myelinated ones

How well did you know this?

Not at all

Perfectly

What does length dependent/glove and stocking neuropathy suggest

SACD of cord
Degen of doral and lateral tracts of cord - mixed proprioception loss, ataxia, hyporeflexia with spasticity and upgoing plantars

How well did you know this?

Not at all

Perfectly

Types of nerve damage

Demyelination - AI, GBS, MS, genetic
Axonopathy - chemo, compression, systemic conditions eg DM

How well did you know this?

Not at all

Perfectly

Most to least myelinated neurons

Alpha motor
Sensory - alpha/beta - vibration/proprioception
Sensory - delta- pain/temp
Autonomic C - autonomic control

How well did you know this?

Not at all

Perfectly

Negative sensory symptoms

Numb
Sensory loss
Proprioception loss
Temp sesnation loss

How well did you know this?

Not at all

Perfectly

Positive sensory symptoms

hypersensitivity
Tingling
Pins and needles
Itching
Neuropathic pain

How well did you know this?

Not at all

Perfectly

Negative motor symptoms

Weakess
Muscle wasting
Hyporeflexia

How well did you know this?

Not at all

Perfectly

Positive motor symptoms

Fasciculations
Cramps

Autonomuc symtoms

Postural hypotension, reduced exercise tolerance
Constipation, gastroparesis
Incontinence, difficulty emptying bladder
Erctility dysfunction
Reduced hypoglycaemia awareness, sweating disturbances

What does parasympathetic NS cause

Safety - constrict pupils, sitmulates saliva, digestion, bile release, peristalsis, bladder contract
Constricts bronchi, slows HR
Vagus nerve, medulla oblongatta

What does sympathetic NS cause

Panic
Dilate pupils
Accelerated HR, dilates bronchi
Inhibits slaive and digestion, peristalsis and secretion
Stimulates glucose release - epinephrine and norepinephrone release
Relaxes bladder
Cahin of sympathetic gagnglia

Timing of neuro symptons - acute, sub acte or chronuc

Acute = hours to days BUT <4 weeks Sub acute = days to weeks. 1-3 minths Chronic = weeks to months >3 months

Areas in nerve damage

Focal - one peripheral nerve- trauma, swelling, compartment, infectionetc Multifocal - more than one area eg mononeuritis multiplex Diffuse - wide area eg bilateral

Types of neuropathy

Sensory Motor Sensorimotor Autonomic

Causes of focal nerve damage

Carpal tunnel syndrome Cubital tunnerl syndrome Meralgia paraesthetica Peroneal nerve injruy

Test for carpal tunnerl

Tinnels and phalens to initiate symptoms - upside down praryer and tap

Risks for carpa tunnel syndrome

- Age, pregnancy, obesity, hypothyroidism Tingling across median distribution, severe causing weakenss

Cubital tunnel syndrome symptoms

Pain, tingling, numbness across ulnar distribution hand, grip/strength problems

What is meralgia paraeesthetica

Entrapment of laterla femoral cutaneous nerve causing pain and paraesthesia over lateral aspect of thigh - sensitive to light touch and heat

What causes meralgia paraesthetica

High weight - compression of nerve by tissue between inguinal ligament and ilium Mangage conservatively - local anaeasthetic

What does foot drop cause

Affects - Biceps, lateral leg compartment and anterior compartment muscles - Sensory - lateral and anterior Abnoraml dorsiflexion, knee flexion, sensory abnormalities in lower leg

What does forehead involevment suggest about a facial palsy

LMN cause - UMN supplies both sides of forehead so would have collateral control

Which nerves are affected first in aconoapthies

Less mmyelinated - pain and temp - first

Causes of axonopathies

- B12 deficiency - Diabetes - Alcohol

What nerves are affeted first in demyelination

Longer more myelinated nerves 0 proprioception, motor control

Causes of demyleination

GBS Chronic inflammatory demyelinating polyneuropathy #Charcot-marie tooth

What antibodies see in [araneoplastic syndrome

Anti-Hu and antiCV2/CRP5 antibodies

What malignancies is paraneoplastic syndrome ass with

small cell lung cancer, B cell lymphoma, waldenstoms macroglobulinaemia

Types of paraneoplastic syndrome

Cerbeallar degneration/ataxia Limbic encephalitis - emotions, behaviours, memory Encephalomyelitis - inflammation of brain and spinal cord Stiff person syndrome Myelopathy - spinal cord Lambert-Eaton myasthenic syndrome Neuromyotonia Opsoclonus-myoclonus

What is lambert eaton syndrome

This is a syndrome caused by disrupted communication between nerves and muscles. Signs and symptoms include pelvic and lower extremity muscle weakness, fatigue, difficulty swallowing, difficulty speaking, irregular eye movement, and double vision. Autonomic nervous system problems can include dry mouth and erectile dysfunction in males. Ass with lung cancer

What conditions can present as a neuropathy

MND Myasthenia gravis Cuada equina Spinal cord cmpression Malignancy

What is first motor loss in peripheral neuropathies

Ankle dorsiflexion

Causes of chronic neuropathies

- Diabetes - Alcohol excess - B12 deficiency - HIV - Medication - chemo, amiodarone, isoniazid - Autoimmune - sjrogens, lupus, sarcoidosis - Lyme disease - Advanced kidney disease - Critical illness - Myeloma/blood dyscrasias

What is charcot marie tooth

Genetic snsorimotor neuropathy - demyelinating. Begins in childhood and causes loss of proprioception and muscle power

Presentation of Charcot marie tooth

Foot drop - hammer toe deformity hooked under Sensorimotor in hands Distal muscle wasting

Genetics of charcot marie tooth

- Duplication of region of short arm chromosome 17 - PMP22 gene involved in myelin synthesis - Autosomal dominant or de novo, some X linked

Investigations for sensorimotor presentation of neuropathy

- FBC - macrocytic anaemia - B12 def, chronic alcohol excess - HbA1c - increased = new diabetes or poorly controlled - U+Es - obvious kidney/electrolyte abnoramlities - CRP/ESR - B12 - TSH - hypothyroidism can cause neuro - HIV/hepatitis - Serum electrophoresis - myeloma MRI brain and spine to exclude central causes NC/EMG