Peripheral Nerve Diseases word

Peripheral Nerve Diseases

The most common forms of peripheral nerve diseases are:
Peripheral Neuropathy: common peripheral nerve disorder could be sensory presenting with paresthesia, numbness and burning sensation in the feet & fingertips then extend to other regions, or Motor or Mixed.(Glove & Stock)

Causes:

Ideopathic Inflammatory Polyradiculoneuropathy:
Acute AIDP (Guillian Barre Syndrome) GBS
Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP).
Metabolic & Endocrine: DM, Thyroid Disorder, Acromegaly, Uremia, Liver Diseases.
Neutritional deficiency: B12, B6, B1.
Infective & Granulomatous Neuropathy: AIDS, Leprosy, Diphtheria, Sarcoid .....etc
Drugs: Alcohol, INH, Phenytoin, Pyridoxine, Metronidazole, Vincristine .......etc
Toxic Neuropathy: Organic : Organophosphorus
Non organic; LEAD, Hg

Neoplastic Neuropathy: Compression, Infiltration or Paraneoplastic reaction.

Hereditory Neuropathy: as Charcot Marie Tooth Disease, Friedreich Disease ....etc
Metabolic : Porphyria, Refsum's Disease, Abetalipoproteinemia ..
Entrapment Neuropathy: CTS, Ulnar nerve....


Investigations:
Hematology: CBC, ESR, B12, & Folate level.
Biochemistry: RFT, LFT, Glucose, Electrolytes.
Immunology: Autoantibodies (ANF, Rheumatoid Factor), VDRL.
NCS-EMG.
CXR.
Cancer Scanning.
Lumbar Punture.
Nerve & Muscle Bx.

Treatment: includes CONTROL OF UNDERLYING DISEASE

Treatment of Painful Peripheral Neuropathy:
AED.s: Gabapentine, Carbamazepine, Pregabalin, Lamotrigine.
Antidepressants:
TCA: Amitryptilline, nortryptilline, Imipramine.
SSRI: Less effective as Fluoxetine, Sertraline.
SNRI: Duloxetine, Venlafaxine.
Antiarrhythmic Drugs: Mexilietine, Flecainide.
Local Treatment: a- Lidocaine Patch.
b- Capsiacine Ointment.


Guillain Barre Syndrome
Acute syndrome of Inflammatory Demyelinating Polyradiculoneuropathy (AIDP) with 1-4 weeks, in 70% postinfectious after Compylobacter diarrhoea or RTI. Cell mediated immune reaction directed at schwan cell due to Molecular Mimicry with some microorganisms Ag.
Clinical Presentation:
Distal paraesthesia & limb pains (often severe) staring in lower limbs, preceding rapidly progressing weakness (Ascending Fashion) from lower to upper limbs symmetrical or mildly assymetrical (more severe proximally). Girdle
Unilteral or bilateral LMNL VII is found up to& 70% of cases, there may be Bulbar and respiratory weakness in about 20% of cases mandating ICU admission & ventilator support.
O/E: Afebrile, weakness of LMNS, on sensory examination features of posterior column dysfunction, there may be evidence of autonomic dysfunction.
Investigations:
1-
CSF Albuminocytological dissociation, other parameters are normal.10 less
NCS-EMG shows evidence of demyelination.
2-
Ix to look for the cause, CXR, Serology for Compylobacter, CMV, Myocoplasma.....
3-
Secondary Infections, DVT, Hyponatremia should be prevented & looked for & appropriated treated if occurs.
Treatment:
Within first two weeks Plasma Exchange PE or IV IgG shorten the duration of ventilation & improve prognosis.
Monitoring respiration with VC & ABG, if VC less than 1L.
80% recover completely within 3-6 months, 5% die, others suffer variable neurological disability.

Miller Fisher Variant

triad of ( Ataxia, Areflexia & External Ophthalmoplegia) unique antiGQ1b Ab.


- Carpal Tunnel Syndrome:

- Entrapment of Median nerve at wrist under the flexor retinaculum.

- Numbness, tingling, burning sensation in hands & 1st 2 & half fingers.
- Pain in anterior wrist may radiate to anterior forearm, prominently at night, relieved by shaking & wrist extension.
- Weakness in thenar muscles while atrophy is late sign.
- TINEL'S TEST: tapping the wrist elicit pain.
- PHALEN TEST: forced flexion of the wrist produces the symptoms.
- Bilateral in 40%, may be associated with:
- overuse of the wrist. – Pregnancy - Myxedema - Rheumatoid

- Diagnosis: - Clinical - NCS Nerve conduction study

- Treatment: - underlying cause - Wrist Splint - NSAID - Local Steroid Injection - Surgical Decompression

AUTONOMIC NEUROPATHY

Is disease of non sensorimotor nervous system mainly affecting internal organs that regulate pulse rate, blood pressure, bowel & bladder functions, could be primary, or associated with Diabetes mellitus, alcohol, certain drugs.

Trigeminal Neuralgia

Reccurent attacks of lancinating pain in V2, V3 territory distribution, in patients over 50 years.
ETIOLOGY aberrant loop of cerebellar artery compresing the nerve or other compressive lesion ex MS plaque.
CLINICALLY severe repetitive very brief pain causing the patient to flinch as if motor tic (Tic Douloureux), may be precipitated by touch, cold wind, eating. It may show Relapsing Remitting Course over years.
Sensory signs are negative their presence should point toward structural lesion as MS, Tumor…etc


TREATMENT:
1-Carbamazepine or Gabapentine or Pregabalin.
2-Phenol or Alcohol injection into the branch of the nerve.
3-Radiofrequency Ablasion near the Gasserian Ganglion.
4-Vascular Decompression Surgery with substantial success.

Bell's Palsy

- LMNL VII, preceding viral illness in 60%, possible association with herpes simplex.
- Progression to plateau within hours to a day, the weakness is variable.
- Weakness of muscles of facial expression(5), 25% with Taste impairment, 10% ear ( Hyperacusis), eye (Bell's Sign) & (CROCODILE tearing).
- Untreated 85% untreated recover completely.
Nerve Conduction Study: to document & assess severity.
- Treatment: - Prednisolone tab 1mg/kg/d for 5-10 days.
- Aciclovir tab 30mg/kg/day. (controversive)
-Electric Nerve stimulation (controversive)