Acute Peripheral Neurological Lesions George Filiadis, D. O. November 17, 2005
Peripheral Nervous System
Serves sensory, motor, and autonomic functions
Sensory symptoms-numbness, tingling, dysesthesias, pain, and ataxia, due to proprioceptive dysfunction
Autonomic symptoms-orthostatic symptoms, bowel or bladder dysfunction, gastroparesis, and sexual dysfunction.
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.
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.
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
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.
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
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.
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
Exraoccular movements are sometimes abnormal
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
Most common form of acute generalized neuropathy
Patients often report recent viral illness, especially gastroenteritis
Associated with Campylobacter jejuni
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
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
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
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
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
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
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
Treatment -acyclovir -Steroid controversial -Eye care to avoid corneal abrasions -lacrilube and patching
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
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
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
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
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
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
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
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
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