This profile screens for the two most common antibodies against streptococcus, DNase antibodies in serum (ADB); antistreptolysin O titer (ASO). These antibodies may cross-react with brain tissue causing abnormal behaviors. Both of these tests are performed to identify a previous infection of group A beta-hemolytic Streptococcus. These infections cause rheumatic fever or a kidney disease called glomerulonephritis, poststreptococcal versions of these diseases, as well as scarlet fever.
Recently, high titers of these antibodies have been associated with PANDAS (Pediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal Infections) and with autism, Tourette syndrome, tic disorder, Parkinson's disease, and OCD.
WHAT ARE PANDAS?
Group A β-hemolytic streptococci (GABHS) infections can cause several immune-mediated diseases. Rheumatic fever (RF), primarily a childhood disease, is a classic example of a complication resulting from a GABHS infection. RF is an inflammatory disease of the heart, joints, and central nervous system that occurs two to three weeks after a GABHS infection. Antibodies that formed against the GABHS organisms cross-react with normal human tissues, causing heart valve damage, inflamed joints and neurological disorders. Sydenham's Chorea, characterized by uncontrolled movements of the face, hands, and feet is a common neurological disorder seen in rheumatic fever caused by the cross reactivity of antibodies with brain tissue. These movements are strikingly similar to motor tics, and many patients also display phonic tics, OCD, and ADHD. This observation, along with reports of sudden-onset tics and psychiatric disorders following an outbreak of GABHS in Rhode Island in the early 1990's, lead to a new diagnostic subcategory of Tourette's syndrome called PANDAs. Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections, or PANDAs, display episodic symptoms of Tourette's syndrome following streptococcal infections. There is often a recovery period as the GABHS antibodies reduce to normal. Helping the brain recover with nutrients may reduce vulnerability to further damage by the strep antibodies.
Serum: 1 mL of serum in a gold-topped SST or royal blue-topped no additive tube.