1. Lead Poisoning and Seizures Dayna Ryan, PT, DPT Winter 2012

2.  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

3.  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 Lead Poisoning

4. Signs & Symptoms  Muscle weakness that can progress to paralysis  affect UEs more, cause wrist drop  Atrophy of muscles  Tremor  Abnormal DTRs (CNS lesion ↑, PNS lesion ↓ )  Chronic exposure in children  Mental retardation, learning disabilities  Hyperactivity, behavior problems  Loss of appetite, vomiting, abdominal pain  Unusual paleness from anemia  Sluggishness, fatigue  Fasciculations (twitches)

5.  Diagnosis  Blood test  Slowed motor NCVs  Fibrillation potential on EMG  Prognosis depending on  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 Lead Poisoning

6. 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

7.  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

8.  General Characteristics  Tonic: jaw fixed, hand clenched  Clonic: rhythmic jerky contractions & relaxation, biting, froth on lips  Non-convulsive: changes in behaviors  Onset  Mostly occur unpredictably at any time  Some are provoked

9. 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

10. 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.

11.  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

12.  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

13.  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 Absence Seizures (Petit Mal)

14.  Diagnosis  History from patient & observation from bystanders  EEG  Identify underlying diseases, rule out other causes  Treatment  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 Epilepsy