PandasChorea

Southern Illinois University School of Medicine

Neurologic Complications of Streptococcal Throat Infections

Streptococcal infections caused by group A beta-hemolytic strep (S. Pyogenes) have been linked to two different neurological syndromes: PANDAS syndrome and Sydenham chorea. These disorders occur in children between the ages of 2 and 12 years, when the incidence of streptococcal throat infections is highest. Although group A streptococci give rise to a long list of infections in humans, throat infections are the main source of neurologic problems. Neuropsychiatric signs and symptoms occur as a delayed sequela of pharyngitis and may be mediated by the immune system. According to prevailing theory, a cross-reaction occurs, and lymphocytes attack the basal ganglia, a cluster of deep brain nuclei that controls movement. They appear to recognize a protein or other substance shared by brain cells and streptococci.

PANDAS Syndrome

First described a few years ago, PANDAS is an acronym for:

P - Pediatric
A - Autoimmune
N - Neuropsychiatric
D - Disorders
A - Associated with
S - Streptococcal Infections

PANDAS Criteria

Presence of OCD and/or tic disorder
Association with streptococcal infection
Episodic course of symptom severity, with "explosive" onset of symptoms, then waxing and waning
Prepubertal symptom onset

PANDAS Features

OCD - Obsessive-compulsive disorder. Having OCD increases the risk of developing tics 10 times.
Tics - involuntary movements of face or shoulders; involuntary sounds. Having tics increases the risk of developing OCD 10 times.
ADHD - attention deficit hyperactivity disorder, which includes distractibility, impulsivity, inattention,m restlessness, and overactivity.
Affective disorder - a disturbance of mood, emotional lability, quick temper.
Anxiety disorder - excessive, inappropriate anxiety.
Choreiform movements - finger twitches when arms are extended (not chorea).

More than 80% of children with PANDAS Syndrome have tics, OCD, and choreiform finger movements. The proportion with ADHD, affective disorder, or anxiety disorder is about 30 to 40%. Three out of four children with PANDAS syndrome are males.

Psychiatric Co-morbidity

Children with PANDAS may display other psychiatric features as well. These alone do not make the diagnosis, as they occur in children without PANDAS syndrome, too.

Avoidant behavior	Enuresis
Bedtime rituals	Nightime fears
Cognitive deficits	Oppositional behaviors
Depression	Overanxious
Emotional lability	Phobias
Encopresis	Separation anxiety

Controversy
PANDAS syndrome is an association with streptococcal infections, not a proven cause and-effect relation. Large epidemiologic studies will be necessary to validate and further define the syndrome.

Syndenham Chorea

Chorea is a major manifestation of acute rheumatic fever (ARF). It is named after Thomas Sydenham, the British physician who first described the clinical features in the late 1600's. Two centuries later, Louis Pasteur first identified streptococci, but another 50 years or so would be required to tighten the links between streptococcal infection and ARF. Also called chorea minor or St. Vitus' dance, after the patron saint of people with chorea, Sydenham chorea may occur without other features of rheumatic fever in about 10 to 20% of patients and take as long as six months after a streptococcal infection to appear. Most episodes last about 3 months. In the absence of an epidemic, acute rheumatic fever occurs in about 0.3% of patients with streptococcal pharyngitis. Girls are affected twice as frequently as boys, but are rarely younger than 5 years old.

Modified Jones Criteria for the Diagnosis of Rheumatic Fever

Major Manifestations
Arthritis	Erythema marginatum
Carditis	Subcutaneous nodules
Chorea

Minor Manifestations
Arthralgia	History of prior rheumatic fever
Fever	Elevated ESR or C-reactive protein
ECG changes
Plus evidence of preceding streptococcal infection

Features
There is an old saying: the child with Sydenham chorea is punished three times-once for general fidgetiness, once for breaking crockery, and once for making faces at his grandmother. The reasons for these behaviors include:

Chorea - involuntary, dance-like movements of limbs on one (20%) or both sides of body (80%) and the face
Dysarthria - jerky, unclear, or absent speech (40%)
Obsessive-compulsive disorder (OCD) - occurs in 70% of the children. Of those, OCD begins before the chorea in 75%.
Hypotonia and muscular weakness - pronator sign, choreic or Warner hand, "milk-maid's grip." Infrequent the weakness is seere (paralytic chorea).
Behavioral poblems - irritabilit, lability, nightmares, agitation or apathy, mental confusion, delusions, hallucinations (chorea insaniens).
Peculiar voluntary movements - desired movements may be performed too rapidly as patient tries to avoid intrusion by chorea, such as in-and-out tongue movement (chameleon tongue).
Seizures - uncommon.

Risks
Chorea recurs in about 20% of patients with Sydenham chorea, usually within 1 to 2 years. Symptoms of Sydenham chorea may return during pregnancy (chorea gravidarum) or while taking oral contraceptives or stimulants (methylphenidate, dextroamphetamine). Recurrent streptococcal pharyngitis can also trigger recurrences. About 25 to 30% of patients develop valvular heart disease.