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Neuropathy classifications: introduction.pptx
- 1. Peripheral Neuropath y Presented by : ZahraaIsmail, PGY2 Supervised by: Dr Abdallah Rahbani
- 2. Definition: Peripheral neuropathies encompassdisorders of peripheral nerves and fibers, manifesting secondary to a wide range of pathologies. The peripheral nerves comprise sensory, motor and autonomic fibers.
- 3. classification: Based onanatomic pattern: I. Mononeuropathy: i. Simplex: involving only one nerve ( median nerve in carpal tunnel, peroneal nerve in drop foot, etc) ii. Multiplex : two or more large nerves that are not symmetrical (mononeuropathy multiplex) II. Polyneuropathy: affects multiple nerves, most of the time, symmetrically iii. Hereditary: ( CMT, HNPP, Refsum dz) iv. Acquired : a. Acute (<4 weeks) b. Subacute (4–12 weeks) c. Chronic (>12 weeks)
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- 6. Mononeuropathy Simplex: A damagethat occurs to a single nerve that can be caused by a variety of factors including trauma, compression and inflammation Nerves that run close to the skin or near a bone are most likely to be affected. These include: • The median nerve in the wrist ( carpal tunnel syndrome) • The ulnar nerve in the elbow. • The radial nerve in the upper arm. • The peroneal nerve just below the knee. • The lateral femoral cutaneous nerve in the legs (meralgia paresthetica).
- 7. Mononeuropathy Multiplex : Mononeuritismultiplex is an asymmetrical, asynchronous sensory and motor peripheral neuropathy involving isolated damage to at least 2 separate nerve areas. Multiple nerves in random areas of the body can be affected The condition is associated with systemic disorders such as: Diabetes mellitus Vasculitis Amyloidosis Direct tumor involvement - Lymphoma, leukemia Polyarteritis nodusa Rheumatoid arthritis Systemic lupus erythematosus Paraneoplastic syndromes
- 8. Hereditary polyneuropathy: CharcotMarie Tooth CMT is the most common inherited neuropathy CMT is caused by pathogenic variants in various genes leading to abnormalities either in the peripheral nerves or the myelin sheath. The most common initial presentation of CMT is distal weakness and atrophy manifesting with foot drop and pes cavus. Sensory symptoms are often present but tend to be less prominent in most CMT subtypes. Later in the course, foot deformities such as hammertoes ensue, along with hand weakness and atrophy.
- 9. Hereditary polyneuropathy: CharcotMarie Tooth
- 10. Hereditary polyneuropathy ● Hereditaryneuropathy with tendencies to pressure palsies (HNPP) ● Refsum Diseases (a rare disorder of lipid metabolism) ● TTR amyloid polyneuropathy
- 11. Acquired polyneuropathy: ● Acute: Guillain-Barre syndrome: o Acute Inflammatory Demyelinating Polyneuropathy (AIDP) o Acute Motor Axonal Neuropathy (AMAN) o Acute Motor and Sensory Axonal Neuropathy (AMSAN) o Miller Fisher Variant (GQ1b antibody) ● Chronic: Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) Metabolic polyneuropathy Toxic polyneuropathy Immune/inflammatory polyneuropathy
- 12. Guillain-Barre syndrome: • Theacute polyneuropathy of GBS is triggered when an immune response to an antecedent event cross-reacts with shared epitopes on peripheral nerve (molecular mimicry). • Most patients report an antecedent infection or other event in the four weeks prior to GBS. Upper respiratory tract infection and gastroenteritis are the most common infections, and Campylobacter jejuni gastroenteritis is the most commonly identified precipitant of GBS. • The typical clinical features of GBS include progressive and symmetric muscle weakness with absent or depressed deep tendon reflexes. Patients may also have sensory symptoms and dysautonomia. Symptoms typically progress over a period of two weeks • The weakness in GBS can vary from mild difficulty with walking to near complete paralysis of all limb, facial, respiratory, and bulbar muscles, depending on disease severity and
- 13. Guillain-Barre syndrome : GBSVariant Type (Demyelinating or Axonal) Time of Onset Peak Time of Symptoms Symptoms Treatment Prognosis AIDP (Acute Inflammatory Demyelinating Polyneuropathy) Demyelinating Days to 4 weeks 2–4 weeks Ascending weakness, areflexia, mild sensory loss IVIG or Plasma Exchange (PLEX), supportive care Good recovery in 6–12 months, ~80% fully recover AMAN (Acute Motor Axonal Neuropathy) Axonal Days to 2 weeks 1–2 weeks Pure motor weakness, rapid progression, no sensory loss IVIG or PLEX, respiratory support if needed Recovery varies; some recover in months, others have residual weakness AMSAN (Acute Motor and Sensory Axonal Neuropathy) Axonal Days to 2 weeks 1–2 weeks Severe motor and sensory loss, rapid progression IVIG or PLEX, aggressive rehab Poorer prognosis, often prolonged recovery Miller-Fisher Syndrome (MFS) Demyelinating (some axonal features) Days to 2 weeks 2–4 weeks Triad: Ophthalmoplegia, ataxia, areflexia, minimal limb weakness IVIG or PLEX, supportive care Good recovery in weeks to months
- 14. Chronic Inflammatory Demyelinating Polyneuropathy(CIDP): • Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) is a chronic, immune- mediated peripheral nerve disorder characterized by progressive or relapsing weakness and sensory loss due to demyelination of peripheral nerves. • It’s caused by an autoimmune-mediated attack on myelin sheath of peripheral nerves by T-cell activation and autoantibody production • Typical CIDP is characterized by a symmetric, motor-predominant peripheral neuropathy that causes both proximal and distal weakness, a sensory impairment that is usually greater for vibration and position sense than for pain and temperature sense, and areflexia.
- 15. CIDP VS GBS Feature CIDP(Chronic Inflammatory Demyelinating Polyneuropathy) GBS (Guillain-Barré Syndrome) Onset Slow, progressive (>8 weeks) Acute, rapid (days to 4 weeks) Course Chronic, relapsing, or progressive Monophasic (one-time episode) Pathogenesis Autoimmune attack on myelin (chronic inflammation) Autoimmune attack on myelin or axons (acute inflammation) Weakness Symmetric, proximal & distal, progressive Symmetric, ascending paralysis (legs → arms → face) Reflexes Absent or reduced (hyporeflexia/areflexia) Absent (areflexia) Sensory Symptoms Numbness, tingling, vibration/proprioception loss Mild sensory loss, tingling Autonomic Dysfunction Less common (some cases) Common (BP fluctuations, arrhythmias) Treatment First-line: IVIG, Plasma Exchange (PLEX), Corticosteroids First-line: IVIG, Plasma Exchange (PLEX)
- 16. Metabolic polyneuropathy: Diabetic •Diabetic polyneuropathy (DPN) is a chronic, progressive nerve disorder caused by long-term hyperglycemia, leading to peripheral nerve damage. It is the most common metabolic polyneuropathy and affects sensory, motor, and autonomic nerves. Hyperglycemia-induced nerve damage via: • Oxidative stress → Mitochondrial dysfunction & nerve injury • Advanced glycation end-products (AGEs) → Disrupt nerve function • Microvascular damage → Reduced blood flow to nerves • Inflammatory processes → Chronic nerve degeneration
- 17. Metabolic polyneuropathy: Diabetic: TypeSymptoms Affected Nerves Distal Symmetric Polyneuropathy (DSPN) (Most common) 🔹 Stocking-glove pattern: Numbness, tingling, burning pain in feet (then hands) 🔹 Loss of vibration & proprioception 🔹 Weakness in severe cases Sensory > Motor Autonomic Neuropathy 🔹 Orthostatic hypotension 🔹 Gastroparesis (nausea, bloating) 🔹 Bladder dysfunction 🔹 Erectile dysfunction 🔹 Sweating abnormalities Autonomic nerves (sympathetic & parasympathetic) Diabetic Amyotrophy (Proximal Neuropathy) 🔹 Severe thigh, hip, or buttock pain 🔹 Weakness in proximal leg muscles 🔹 Muscle atrophy Lumbar plexus (Femoral, Obturator nerves) Mononeuropathy (Focal Neuropathy) 🔹 Sudden cranial or peripheral nerve palsies (e.g., CN III, VI, VII) 🔹 Median nerve (carpal tunnel), Ulnar nerve Single nerve involvement Mononeuritis Multiplex 🔹 Asymmetric, painful weakness in multiple nerves 🔹 Affects random nerves (e.g., peroneal → foot drop, radial → wrist drop) 🔹 Can progress to distal symmetric polyneuropathy if untreated Multiple, patchy peripheral nerves
- 18. Metabolic polyneuropathy: VitB12 Deficiency Vitamin B12 deficiency causes demyelination and axonal degeneration of peripheral nerves, spinal cord (posterior & lateral columns), and the brain, leading to sensory, motor, and autonomic dysfunction. Common causes: • Dietary deficiency (vegan diet) • Malabsorption (pernicious anemia, gastric bypass, Crohn’s disease) • Medications (metformin, PPIs)
- 19. Metabolic polyneuropathy: VitB12 Deficiency: Category Symptoms Pathology Sensory Symptoms 🔹 Glove-and-stocking sensory loss 🔹 Tingling, numbness, burning 🔹 Loss of proprioception & vibration → Ataxia Dorsal column demyelination (posterior cord syndrome) Motor Symptoms 🔹 Weakness (late-stage) 🔹 Spasticity & hyperreflexia in severe cases 🔹 Positive Babinski sign Lateral corticospinal tract demyelination (upper motor neuron involvement) Autonomic Symptoms 🔹 Orthostatic hypotension 🔹 Bladder dysfunction Peripheral & autonomic nerve involvement Neuropsychiatric Symptoms 🔹 Memory loss, confusion 🔹 Depression, irritability 🔹 In severe cases: Dementia, psychosis Brain involvement
- 20. Metabolic polyneuropathy: VitB6 Deficiency: Vitamin B6 (pyridoxine) deficiency leads to peripheral neuropathy, characterized by sensory disturbances, irritability, and in severe cases, seizures. It affects both the central and peripheral nervous systems. Common Causes: • Malnutrition (alcoholism, chronic illness) • Medications (Isoniazid, Hydralazine, Penicillamine, Levodopa) • Pregnancy & Dialysis (Increased B6 demand)
- 21. Other forms ofacquired polyneuropathy: ● Toxic : Arsenic Lead Thallium Organophosphates Drug induced: chemotherapy, metronidazole, nitrofurantoin, lithium ● Immune/Inflammatory: Paraneoplastic Amyloidosis Sarcoidosis Paraproteinemic ● Small sensory fibers polyneuropathy ( ex: Fabry disease) ● Infectious polyneuropathy: HIV-Associated Neuropathy Leprosy (Hansen's Disease) Varicella Zoster Virus (VZV) Neuropathy Cytomegalovirus (CMV) Neuropathy Lyme Disease Hepatitis C Virus (HCV) Neuropathy
- 22. Skin Manifestations associatedwith neuropathies Type of Polyneuropathy Skin Manifestations Diabetic Polyneuropathy 🔹 Dry, cracked skin 🔹 Hair loss on legs 🔹 Shiny, thin skin 🔹 Foot ulcers & poor wound healing Vitamin B12 Deficiency Neuropathy 🔹 Pale skin (pernicious anemia) 🔹 Glossitis (red, swollen tongue) 🔹 Hyperpigmentation (in some cases) Toxic Neuropathy (e.g., Arsenic, Thallium) 🔹 Hyperpigmentation & Mees’ lines (arsenic poisoning) 🔹 Alopecia (hair loss, thallium poisoning) 🔹 Exfoliative dermatitis Alcoholic Neuropathy 🔹 Erythema of palms 🔹 Spider angiomas 🔹 Glossitis & cheilitis (due to vitamin deficiencies) Leprosy (Hansen’s Disease) – Infectious Neuropathy 🔹 Hypopigmented, anesthetic skin patches 🔹 Nodules, thickened skin 🔹 Loss of eyebrows (madarosis) Fabry Disease (Genetic Polyneuropathy) 🔹 Angiokeratomas (small red/purple skin spots) 🔹 Hypohidrosis (reduced sweating) Mees’ lines (arsenic poisoning)
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