People who have tics or Tourette Syndrome often also have OCD-like behaviors. Those affected with Obsessive-compulsive disorder (OCD) have agonizing irrational thoughts (obsessions) that lead to a strong emotional reaction, such as anxiety or disgust, and they often use repeated excessive behaviors (compulsions) to reduce this anxiety.
In 2015, NJCTS published these general statistics on comorbidities in TS:
- 25%-50% of people with Tourette or Chronic Tic Disorder meet the criteria for a formal diagnosis of OCD
- 80% of people with Tourette or Chronic tic disorder may have obsessive compulsive behaviors
- 30% of people with OCD have a family history of co-occurring Tourette or Chronic Tic Disorder
A lot of recent research including twin studies, neuroimaging studies, and a genome-wide complex trait analysis, suggest that there is a significant genetic association between TS and OCD.
However, recently it was reported that Pediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal infection (PANDAS) and Pediatric Acute onset Neuropsychiatric Syndrome (PANS) can lead to an onset of OCD and tics. PANDAS can occur when an infection, such as strep, causes the immune system to attack the body’s healthy cells, often, cells in the brain. The strep bacteria disguise themselves to look like normal cells. When the immune system eventually finds and fights them, it sometimes also fights the cells that the strep is imitating. Unlike PANDAS, which only comes from strep, PANS has multiple etiologies and disease mechanisms.
It is frequently asked if Tourette Syndrome is related to PANDAS or PANS. The symptoms may seem similar and a lack of understanding about these complex disorders can result in misdiagnosis. Tourette Syndrome is a neurological disorder. Although the cause is clearly known, genetic studies indicate that TS is inherited as a dominant gene. A person with TS has about a 50 percent chance of passing the gene to one or more of his/her children. This genetic predisposition may express itself as TS, a milder tic disorder or obsessive compulsive symptoms with no tics at all. TS is a diagnosis that doctors make after verifying that the patient has had both motor and vocal tics for at least 1 year.
With PAN or PANDAS, your child may seem to turn into a different person overnight, becoming moody, anxious, aggressive, displaying obsessive compulsive behaviors, and dealing with body movements they can’t control.
“Pediatric Acute-onset Neuropsychiatric Syndrome (PANS) is a clinical diagnosis given to children who have a dramatic – sometimes overnight – onset of neuropsychiatric symptoms including obsessions/compulsions or food restriction. They are often diagnosed with obsessive-compulsive disorder (OCD) or an eating disorder, but the sudden onset of symptoms separates PANS from these other disorders. In addition, they may have symptoms of depression, irritability, anxiety, and have difficulty with schoolwork. The cause of PANS is unknown in most cases but is thought to be triggered by infections, metabolic disturbances, and other inflammatory reactions.
Like PANS, children with Pediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal Infections (PANDAS) have an acute onset – within 2 to 3 days – of neuropsychiatric symptoms, specifically OCD or tics (involuntary, purposeless movements). However, PANDAS patients test positive for a recent streptococcal infection, such as strep throat, peri-anal strep or scarlet fever. Like PANS patients, they also may suffer from uncontrollable emotions, irritability, anxiety and loss of academic ability and handwriting skills. Although PANDAS was identified as a medical syndrome more than a decade before PANS, it has been classified as a subset of PANS. To date, PANDAS is the only known subset of PANS, but we may discover more causes in the future.”Stanford Medical
A test for the strep bacteria or a history of the bacteria is necessary to confirm your child has PANDAS, which can mimic other disorders. If your child doesn’t or didn’t have strep, they don’t have PANDAS, but he or she could be having the symptoms because of PANS. The symptoms are similar, but they may be triggered by something other than strep. Similarly, if the child’s symptoms came on suddenly and reached peak severity within 24-48 hours, the diagnoses of PANS and PANDAS should be considered.
People with PANS/PANDAS can experience symptoms that do not typically occur in people with Tourette Syndrome. Children with PANS/PANDAS sometimes experience a personality change not usually seen in people with TS. Physical symptoms such as increased urinary frequency, involuntary urinations, difficulty swallowing, dilated pupils, and other symptoms may also occur.
However, some people PANS/PANDAS may present predominantly with tics, OCD, and ADHD, so the case may look very similar to TS except for the timing and possibly the existence of strep. Antibiotics often reduced or resolve PANS symptoms, whereas they do not have the same effect on Tourette Syndrome symptoms.
Ultimately, receiving the proper diagnosis will result in the correct care. A thorough understanding of the timing of the onset of symptoms, and any underlying causes such as strep is necessary for reaching the correct conclusion. For an in-depth analysis of PANS/PANDAS and the overlap with other syndromes, visit Aspire Care and Stanford Medicine