1. Acute Peripheral Neurological Lesions George Filiadis, D. O. November 17, 2005

2. Peripheral Nervous System Serves sensory, motor, and autonomic functions Sensory symptoms-numbness, tingling, dysesthesias, pain, and ataxia, due to proprioceptive dysfunction Motor symptoms-weakness Autonomic symptoms-orthostatic symptoms, bowel or bladder dysfunction, gastroparesis, and sexual dysfunction.

3. Peripheral Nervous System In peripheral nerve process there is reduction or absence of reflexes. When the sensory component is involved, test for proprioception, vibratory sensation, and pain and temperature sensibility When the motor system is involved there is wasting, fasciculations, and weakness. Autonomic dysfunctions may cause anhidrosis, pupillary dysfunction, orthostatic hypotension, and tachy- and bradyarrhythmias.

4. Localization of neurological disease See Figure 233-1 Most muscle-related processes result in weakness of large proximal muscles along as pain, tenderness, and elevation of CK. Diseases that affect other components of the peripheral nervous system seldom cause tenderness and elevation of CK. Neuromuscular junction processes can affect large proximal muscles and affect bulbar musculature resulting in pupillary dysfunction, diplopia, dysarthria, or dysphagia.

5. Myopathies Polyomyositis -Inflammatory myopathy -chronic complaints of proximal symmetric weakness -may have muscle pain and tenderness -may have dysphagia and few progress to respiratory failure -no sensory loss, reflexes should be intact

6. Polyomyositis Management -should be assessed for potential respiratory compromise and aspiration risk. -long term treatment-immunosuppressive agents such as steroids and methotrexate Differential diagnosis includes Lambert-Eaton myasthenic syndrome, inclusion body myositis, toxic myopathies, and dermatomyositis.

7. Myopathies Dermatomyositis -Can affect children -similar to polyomyositis except for violaceous rash over face and hands -muscle weakness -no sensory or reflex abnormalities -treatment is immunosuppression -elevated sed rate and CPK

8. Other Myopathies Drug induced –see table 233-1 Viral myositis causes an acute myopathy involving the heart, associated with febrile illness, myalgia, and elevated CK levels. Suspect trichinosis in pt with myalgias, proximal and bulbar muscle weakness, facial edema, and eosinophilia.

9. Disorders of the Neuromuscular junction- Botulism Ingestion of food contaminated with Clostridium botulinum. Adults often report exposure to home canned foods Infants exposure to honey Bulbar weakness Exraoccular movements are sometimes abnormal

10. Botulinism Absence of pupillary light reflex Proximal limb weakness Sensation is intact, normal mentation, reflexes are usually normal Treatment-antibiotics in infants and immune serum and admission to the hospital

11. Guillain-Bare Syndrome Most common form of acute generalized neuropathy Patients often report recent viral illness, especially gastroenteritis Associated with Campylobacter jejuni

12. Guillain-Barre Syndrome Numbness and tingling of the lower extremities followed by weakness of the legs and then arms. Weakness more pronounced in the legs Lack of deep tendon reflexes May be facial weakness involving the forehead Chance of respiratory failure and lethal autonomic fluctuations

13. Guillain-Barre Syndrome Management -Lumbar puncture (high CSF protein, nl cell count and glucose) -Should be admitted for monitoring -When vital capacity is under 1 liter, intubate. -Plasma exchange or IV immunoglobulin

14. Focal neuropathies-Carpal Tunnel Syndrome Most commonly see entrapment neuropathy. Intermittent pain and/or numbness in the thumb and first two fingers. Symptoms reproduced with compression of the nerve over the carpal tunnel or by tapping over the nerve. Treatment-wrist splints and ortho referral

15. Focal neuropathies Ulnar neuropathy -Numbness of the fourth and fifth fingers -weakness and wasting of hypothenar eminence is late finding Entrapment of deep peroneal nerve -at the fibular head causing foot drop and numbness of the web between great and second toe

16. Focal Neuropathies Meralgia paresthetica -entrapment of lateral femoral cutaneous nerve of the thigh. -numbness and dysesthesias on lateral aspect of upper leg. -usually after weight loss or pelvic procedures

17. Focal neuropathies Mononeuritis multiplex -multiple nerve dysfunctions caused by vasculitis -usually affects both sides of the body -differential diagnosis includes multiple compression neuropathies and multifocal motor neuropathy

18. Focal Neuropathies-Bell’s Palsy Most common cause of acute facial paralysis Sudden facial weakness, difficulty with articulation, problems keeping an eye closed, or inability to keep food in the mouth one side. One sided weakness of the face involving the forehead

19. Bell’s Pulsy Treatment -acyclovir -Steroid controversial -Eye care to avoid corneal abrasions -lacrilube and patching

20. Focal neuropathies-Lyme disease Multiple neurologic manifestations Arthralgias and fatique initially Common neurologic sign is seventh nerve pulsy Weakness in the limbs May see selected decreased deep tendon reflexes

21. Lyme Disease Management -serum and CSF lyme antibodies -CSF pleocytosis and increased protein with a normal glucose -treat with 3 week course of IV antibiotics either rocephin or doxycycline

22. Plexopathies-Brachial Neuritis Affects younger individuals Excruciating back, shoulder, or arm pain followed by weakness of arm or shoulder girdle. On exam there is weakness along the distribution of brachial plexus. Differential diagnosis includes cervical radiculopathies, Pancoast tumor

23. Plexopathies-lumbar Occurs in diabetic patients Presents with back pain followed by weakness. Sensory findings are absent Deep tendon reflexes are diminished on the affected side. Bowel and bladder function are not affected

24. HIV-Associated Peripheral Neurologic Disease CMV radiculitis -may be seen in the latter stages of AIDS -Acutely weak -Primarily lower extremity involvement -Varying degrees of bowel and bladder dysfunction -Hyporeflexia and decreased sensation -Rectal tone may be impaired

25. CMV Radiculitis Management -lumbar puncture reveals pleocytosis and increased protein -MRI of lumbarosacral spine demonstrates swelling and clumping of cauda equina -IV gancyclovir started at 5mg/kg q 12 h X 14 d

26. Questions Which of the following includes bulbar muscle weakness, absent pupillary reflex, and proximal muscle weakness a. polyomyositis b. botulism c. Guillain-Barre d. Lyme disease

27. Questions All of the following are associated with Lyme disease except a. Tick Exposure b. Seventh nerve pulsy c. Arthralgias and fatigue d. abnormal mentantion e. treatment with rocephin or doxycycline. Answers: b, f, t, d

28. Questions In Guillain-Barre Syndrome, deep tendon reflexes are intact T/F Myalgias, proximal and bulbar muscle weakness, facial edema and eosinophilia are associated with Trichinosis T/F