Epilepsy and Lead Poisoning
Download
Report
Transcript Epilepsy and Lead Poisoning
Lead Poisoning and Seizures
Dayna Ryan, PT, DPT
Winter 2012
Lead Poisoning
Overview
Normal blood lead level is “0”
Toxicity is not evident until blood lead levels build up over
months or years
Toxic threshold is lower in children & pregnant women
High levels can be fatal
Lesion Site
CNS or PNS
In children: brain (encephalopathy with scattered
hemorrhages)
In adults: peripheral myelin or axon (peripheral neuropathy)
Lead Poisoning
Etiology
In children: lead-based paint in old building
(prior to 1978)
Contaminated air, water, soil, toys, glazed
dishware, imported canned food, cosmetics
Onset
After months of exposure unless large amount
Faster absorption with inhalation
Signs & Symptoms
Muscle weakness that can progress to paralysis
Atrophy of muscles
Tremor
Abnormal DTRs (CNS lesion ↑, PNS lesion↓)
Chronic exposure in children
affect UEs more, cause wrist drop
Mental retardation, learning disabilities
Hyperactivity, behavior problems
Loss of appetite, vomiting, abdominal pain
Unusual paleness from anemia
Sluggishness, fatigue
Fasciculations (twitches)
Lead Poisoning
Diagnosis
Prognosis depending on
Blood test
Slowed motor NCVs
Fibrillation potential on EMG
Length & level of lead exposure
Whether myelin (initial exposure) or axon (prolonged exposure)
is damaged
Treatments
Remove the source!
Chelating agents to bind the lead so that it's excreted in the urine
Epilepsy / Seizure
“Electrical storm in the brain”
Epilepsy
Chronic disorder characterized by recurrent episodes of
seizures due to excessive discharge of cerebral neurons
Seizure
Involuntary movement or convulsions
Altered mental awareness
Due to excessive electrical activity in the brain
Etiology
Mostly idiopathic (unknown)
Genetic predisposition in 1% of
cases
Any major disease or illness
In older adults age > 50, CVA is # 1
cause
Chaotic excessive electrical
discharge of large aggregates of
neurons in the brain
Onset
Mostly occur unpredictably at any time
Some are provoked
General Characteristics
Tonic: jaw fixed, hand clenched
Clonic: rhythmic jerky
contractions & relaxation, biting,
froth on lips
Non-convulsive: changes in
behaviors
Classification of Seizure
Partial seizure
Simple partial
Complex partial
(most common)
Generalized seizure
Tonic-Clonic
(i.e. Grand Mal)
Absence
(i.e. petit mal)
**most common type
Sometimes, simple or complex
partial can develop into
generalized tonic-clonic
Simple Partial (focal seizure)
Patients are conscious during seizure
Unilateral hemispheric involvement, from a distinct,
focal area of cerebral cortex
Symptoms could
be motor,
somatosensory, or
visual, depending
on the brain area
involved.
Complex Partial
Altered or loss of consciousness
Involve bilateral hemispheres, usually temporal lobes
Automatic,
involuntary,
repetitive
behaviors
Clumsy
movements
Confused,
mumbling, pulling
clothing, head
turns
Tonic-Clonic (grand mal)
Sudden loss of consciousness & fall
Tonic: generalized rigidity
Clonic: very rapid generalized jerking movements
Postictal: altered speech, weakness, disorientation, muscle
soreness, HA
Absence Seizures (Petit Mal)
Sudden cessation of ongoing
consciousness activity
Stares into space
Only minor convulsive muscle
activity or loss of postural
control
Simple, brief, automatic
movements
More common in children,
usually remit in adulthood
Epilepsy
Diagnosis
Treatment
History from patient & observation from bystanders
EEG
Identify underlying diseases, rule out other causes
Education
Anticonvulsants (e.g. Gabapentin)
Surgery
Vagal nerve stimulation – sends inhibitory signals to cerebrum
Prognosis
Increased mortality rates (due to underlying condition)
Death from asphyxia (eating or swimming during a seizure)
20 X risks of sudden death (cardiac arrhythmia, MI)
Remission = 75% in idiopathic seizure diagnosed before age 10