|
 |
Neurology
| |
EDUCATION
Emory Pediatric Neurology Teaching Syllabus
Emory University School of Medicine
Atlanta, Georgia U.S.A, 404-727-5756
Disorders with Abnormal Movements
Tics are rapid, non-voluntary, repetitive segmental movements. Simple Tics usually occur in one muscle group or segment
and last less than 6 months. Simple tics occur in about 50% of children. Chronic Tics last longer than 6 months. Tics are
usually low amplitude with only mild to moderate forcefullness. However, some tics can be very forceful and strong so that
the child is have discomfort for the intensity of the movement.
Tourette Syndrome
Tourette Syndrome is a condition of motor tics and vocalizations lasting longer than 12 months, starts between 2 and 10 years
of age, and may fluctuate in severity over time. Children have motor tics (blinking, grimacing, shrugging, torso flexion and
jerks of head ...) and vocalizations (vocal or phonic tics such as barking, grunting, sniffling, coughing...) only while
awake. Tics may seem to come and go and often as one tic becomes less frequent or severe, another tic in another muscle group
develops. Mannerism and compulsions are common. Tourette Syndrome is much more common in males with male to female ratios 3:1
to 5:1 reported. The most common ages of onset 4 to 6 years of age with 50% having co-morbid ADHD, LD, or OCD. Remission after
puberty is reported in 2/3s, with about 1/4 staying the same and the rest <1/10 worsening. Coprolalia reported in 8%. Family
History often positive for OCD. Treatment with clonidine (Catapres), haloperidol (Haldol), or pimozide (Orap) for tics with
the latter 2 having risk of acute dystonia, akathesia. 15% may be unmasked (? precipitated) by stimulant medication.
Further Tourette Syndrome Resources
- Tourette Syndrome Association of Georgia, Inc.
P. O. Box 768413
Roswell, Georgia 30076
770-645-5775
Outside Metro-Atlanta Calling Area: 1-888-799-2101 (www.tsaofga-sc.org/a>)
- The National TSA web site is hosted at http://tsa.mgh.harvard.edu.
- The Jim Eisenreich Foundation for Children with Tourette Syndrome www.tourettes.org.
PANDAS
(Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections
PANDAS, is a term used to describe a subset of children who have Obsessive Compulsive Disorder (OCD) and/or tic
disorders such as Tourette's Syndrome, in whom symptoms typically worsen following strep infections such as "Strep throat".
The children usually have dramatic, "overnight" onset of symptoms, including motor or vocal tics, obsessions, compulsions, or
a combination of all. This abrupt onset is generally preceeded by a Strep throat infection.
The mechanism behind this phenomenon is unknown but researchers at the NIMH are pursuing a theory that the mechanism is
similar to that of Rheumatic Fever, an autoimmune disorder triggered by strep. throat infections. In every bacterial
infection, the body produces antibodies against the invading bacteria, and the antibodies help eliminate the bacteria from
the body. However in Rheumatic Fever, the antibodies mistakenly recognize and "attack" the heart valves, joints, and/or
certain parts of the brain. This phenomenon is called "molecular mimicry", which means that proteins on the cell wall of
the strep. bacteria are similar in some way to the proteins of the heart valve, joints, or brain. Because the antibodies
set off an immune reaction which damages those tissues, the child with Rheumatic Fever can get heart disease (especially
mitral valve regurgitation), arthritis, and/or abnormal movements known as Sydenham's Chorea or St. Vitus Dance.
In PANDAS, it is believed that something very similar to Sydenham's Chorea occurs. One part of the brain that is affected
in PANDAS is the Basal Ganglia, which is believed to be responsible for movement and behavior. Thus, the antibodies interact
with the brain to cause tics and/or OCD, instead of Sydenham Chorea.
This statement is an edited version of PANDAS information on the NIMH web site http://intramural.nimh.nih.gov/research/pdn/gen_info.htm
which also has further links.
Because of this suspected auto-immune phenomenon, treatments directed to remove the antibodies or block the action of
antibodies have been tried to treat PANDAS. In trials of Plasma Exchange and Intravenous Immunoglobulin at the NIH no
proven benefit for PANDAS was found and these treatments carry risk for children with PANDAS, Tourette´s Syndrome, and
OCD. Further information on treatment is available at the NIH http://www.nimh.nih.gov/events/pandaalert.cfm.
Chorea
Chorea is slow, large amplitude involuntary movements of proximal more than distal muscles. Causes: post-viral, anti-cardiolipid
syndrome with lupus, toxic(heavy metals), drugs, trauma, post anoxic (asphyxia and hypothermic post cardiopulmonary by-pass),
metabolic encephalopathies (hepatic, renal, parathyroidism, high and low sodium) and strep, i.e.
Sydenham's Chorea. Chorea is a "Major Jones criteria" for Rheumatic Fever. In Sydenham's Chorea, facial and upper
extremity involvement that is often asymmetrical (18% unilateral). There is also hypotonia, and weakness with onset at age
3 to 18 years of age. Sydenham's Chorea is more likely in females more than males and can last from 1 month to 2
years. Dysarthria, dyskinesias, and milk maid grasp. Chorea will suppress with haloperidol.
Ataxia
Ataxia is unsteady movements or inability to control movements and typically is caused by cerebellar dysfunction from
irritation or disruption of cerebellar tracts. Loss of peripheral sensory input can also cause ataxia.
Causes of Ataxia
- drugs: alcohol, anticonvulsants (sedation)
- cerebellar mass: tumor, abscess or hematoma (ICP)
- infection: (Hemophilus influenza meningitis)
- Post- or para-infectious: varicella, measles, mumps
- GBS: areflexia and weakness
- Neuroblastoma: opsoclonus, myoclonus syndrome
Freidreich’s Ataxia
Freidreich’s Ataxia(FA) is an autosomal recessive disorder with onset age 2 -10 years. FA presents with delayed onset
of walking or stumbling, "cerebellar speech" ( staccato, explosive quality from incoordination of respiration
and phonation), ataxia, nystagmus, kyphoscoliosis, pes cavus foot. As FA progresses patients develop dysphagia and
become bed ridden prior to death. Myocarditis occurs in 90% (T wave change, Interventricular septal hypertrophy, heart
block with eventual CHF) and insulin dependent diabetes develops in 25 to 75% of patients.
Ataxia-Telangectasia
Ataxia-Telangectasia is a progressive disorder with ataxia, choreo-athetosis, telangectasia of the lateral sclera, Low
IgA, tendency to develop lymphoreticular malignancies (Burkett’s Lymphoma), and elevated alpha-fetoprotein(AFP). A child
with progressing ataxia can be diagnosed with AT if the AFP is elevated. Caused by "AT Mutant (ATM) gene" (Chromosome
11q22-q23) abnormal DNA repair. Further information available at the Ataxia-Telangectasia Children's Project web site.
Tremor
Tremor is a regular osillatory movement of the extremities related to posture or activity. Benign Familial Tremor (BFT) or
essential tremor can start at any age and is about 3/sec, present in the hands during fine motor activities and with posture
resisting gravity. BFT is not present at rest or when not resisting gravity. Treatment with propranolol will dampen but not
always stopping the tremor. The tremor is magnified with stress and fatigue. Patients with BFT usually have a characteristic
very shakey appearing handwriting. Children with BFT are often referred because of extremely bad penmanship. Education to
accept the tremor and reduce the family's anxiety and conflicts with the school may be sufficient treatment. Resting
tremors are less common in children and can be produced by juvenile Parkinson's, Wilson's disease, drugs, mercury
posioning, or idosynchratic.
|
| Feedback |
|
|
|
