Peripheral Neuropathy

Routine for examination of lower limbs:

 

Inspect (walking aids, wasting, fasciculations, pes cavus, calluses, ulcers, charcot joint)

Tone

Power

Reflexes

Sensation: light touch, joint position sense, vibration and pin prick if time allows. Be sure to test both proximally and distally and to determine the level at which sensation returns to normal (start distally and work proximally) and test the back of the leg too!

Coordination

Gait and Rhombergs

 

If time allows:

 

Hands: sensation (NB: hands usually only affected if sensory loss in lower limbs is beyond the knees)

General exam for clue to cause: hands (dupuytrens contracture, diabetic fingerprick marks, clubbing, vasculitic changes, wasting), arms (fistula), eyes (conjunctival pallor), abdo (renal, insulin injection sites), thyroid

 

 

Present to the examiner:

 

This patient has a predominantly sensory peripheral polyneuropathy as evidenced by:

 

Distal (a)symmetrical loss of sensation to light touch (and pinprick +/- vibration) in stocking distribution to knees

Loss of joint position sense at toes (+/-ankle etc)

Comment on whether there was a stomping broad based gait and whether Rhombergs was positive

Comment on whether the motor system was intact

Comment on whether the ankle jerk was present/absent

Comment on whether there was any ankle deformity, calluses, ulcers, pes cavus etc.

There was (no) sensory loss in the upper limbs

With regards to a cause, I looked for …….

 

I would complete my examination by examining motor and sensory systems in the upper limbs, cranial nerves and performing fundoscopy.

 

 

Investigations:

 

Level 1:            FBC, U+E, LFT, TFT, ESR, CRP, B12, folate, glucose/hba1c, bone profile

Urine dipstick

Level 2:            ANA, ANCA, Immunoglobulins, RF, complement, serum electrophoresis, urine bence jones proteins, serum ACE, paraneoplastic antibodies (eg. anti-mag, anti-hu, anti-yo), HIV, syphilis, lyme, coeliac serology

CXR

EMG (denervation)

Nerve conduction studies (sensory vs. motor, low amplitude = axonal, low velocity = demyelinating)

 

Level 3:            Lumbar puncture for CSF examination

MRI spine

Nerve/muscle biopsy

Screen for cancer: mammogram, CT, skeletal survey if possible myeloma

Genetic testing

 

Causes of  predominantly sensory peripheral neuropathy:

 

*ABCDEFGHI*

 

A          Alcohol (and liver dysfunction)                                               LFTs

B          B12, B1 deficiency                                                                       FBC, B12

C          Cancer, chemo, CKD, coeliac, connective tissue disease   U+E, multiple myeloma

screen, paraneoplastic screen, CXR, mammogram, coeliac,  ESR, ANA, ANCA, RF, Igs,

complement, etc.

D          Diabetes, Drugs (and toxins)                                                  Hba1c

E          Endocrine                                                                                    TFTs

F          Folate deficiency                                                                         Folate

G          Granulomatous disease eg. sarcoid                                        Calcium, serum ACE

H          Hereditary eg. HSMN

I           Infection eg. leprosy, idiopathic                                              HIV, syphilis, lyme etc.

 

 

Drug causes:

 

Isoniazid, ethambutol

Vincristine, vinblastine

Cisplatin, oxaliplatin

Phenytoin

Metronidazole, nitrofurantoin

Gold, ciclosporin

Amiodarone, hydralazine

Antiretroviral drugs

 

Management:

Conservative: physio, OT, orthotics, social worker, DVLA considerations, stop drinking alcohol if this is the cause/contributing, diabetic specialist nurse and doctor if diabetes is the cause/contributing

Medical: analgesia, treat the underlying cause

 

 

Written by Dr Sarah Kennedy

 

Resources used to write this document are listed in the references section of this webpage