OCD After a Sore Throat?

Mindd Foundation


Dr Leila Mason on how OCD can result from a sore throat

In my practice I regularly see children who have all of a sudden become very anxious. They present with a change in personality from a confident and happy child to one with severe separation anxiety, new fears and sometimes OCD behaviours and tics.

Along with the parent, I try to figure out what the source of this change could be: stress at home, pre-school, or school?  If we do find a possible reason this needs to be addressed by the family and school; a counsellor or therapist may be helpful.

Is a Sore Throat the Culprit for OCD?

However, sometimes we do not come up with any obvious psychological reason for the anxiety, OCD behaviours, and tics.  But when I go through the medical history I find out more often than not that the child had a sore throat in the recent past. Could it be that the sore throat had something to do with the OCD behaviour and anxiety?

What the Reseach shows

Researchers from the National Institutes of Health in the USA have done research on this association and given it a name: PANDAS or paediatric autoimmune neuropsychiatric disorders associated with streptococcal infections.

What happens in the body is fascinating: the immune system produces antibodies against the streptococci in the throat to fight the infection. Streptococci have evolved to hide from our immune system by covering themselves with proteins that look very similar to the proteins on human organs – this is called molecular mimicry and allows strep to survive “undercover”.

Antibodies Attack Vital Organs including the Brain

In some people, the antibodies produced to kill streptococci recognize cells in the human body, for example, cells in the heart (this is called rheumatic fever), the kidneys, the skin, the joints, and even the brain, and start attacking them as well.

In the case of the brain, the immune reaction attacks the basal ganglia and causes inflammation.

Typically a child between 3-14 years of age:

  • suddenly becomes scared of separation
  • develops new intense fears
  • OCD behaviours
  • tics and
  • their handwriting changes drastically
  • maths skills may deteriorate
  • the child may have problems sleeping and need to urinate frequently
  • the behavior can regress to that of a younger age and
  • some children become oppositional and aggressive or depressed.

I find that many children will also develop a spotty rash on the buttocks – possibly from streptococci overgrowing in the gut (remember that the throat is connected to the rest of the gut and if you have a florid strep throat, you will swallow strep bacteria and they may survive in the gut and grow all the way into the colon, then exit the body through the anus with a few bacteria spreading to the skin, ie the buttocks and cause pimples there).

The hallmark of the diagnosis though is the sudden onset of anxiety and obsessive behavior.

How the OCD Diagnosis is Made

The diagnosis is made with

  1. a throat swab for streptococci and
  2. a simple blood test for antibodies to streptococci.

The throat swab will only be positive if the infection is still present. Sometimes the auto-immune reaction happens 2-4 or even more weeks after the throat infection and by then the throat swab is most likely negative.

The blood tests for antibodies are called ASOT (Anti-Streptolysin O titre) and anti-DNAse B. They are ideally done twice – within 2 weeks of the onset of the symptoms and again 4-8 weeks later. If the result increases fourfold, this is indicative of PANDAS. If it has been longer than 2 weeks since the beginning of the symptoms and you cannot get the two separate blood tests done, just one blood test that is elevated is enough to give you an idea as to whether you are dealing with PANDAS or not, but cannot definitively prove it. A low blood level of ASO alone does not rule out PANDAS. If your child has the combination of a history of a sore throat and sudden onset of anxiety, OCD behavior and tics, I would be very concerned about PANDAS and find a doctor who can assess and treat your child.

How to Treat the Infection and Cause of the Symptoms

Since the cause of the sudden anxiety, in this case, is an infection, the treatment consists of antibiotics. Usually, Penicillin will be prescribed, just as for rheumatic fever, where the streptococci attack the heart.

Often the symptoms will improve dramatically within a few days of taking antibiotics. I recommend a course of probiotics along with the antibiotics. It is important to choose the appropriate probiotics – streptococci produce lactic acid; as the name suggests this increases the acidity in the body; I try to avoid other lactic-acid producing probiotics (such as lactobacilli) and may choose E coli or bifidobacter bacteria containing probiotics for that reason.

The child may also benefit from immune-boosting nutrient support: typically children with a poor immune system may lack zinc, selenium, or vitamin D. Vitamin C may also be helpful in overcoming infections and is safe to take.

Once the antibiotics are stopped, it may be helpful to continue with a herbal supplement that suppresses the growth of streptococci, such as olive leaf extract.

The diet should be low in sugar, as sugar is the preferred food of streptococci. Legumes, on the other hand, are the ideal food for growing E coli, beneficial gut bacteria that can suppress the growth of streptococci in the gut.

In my experience, most children respond quickly to treatment with antibiotics, supported by probiotics. Some children develop the same symptoms again several months or a year later. I always wonder why this may be happening: could it be due to another streptococcal infection, exposure to a friend or family member who carries the bacteria in their throat or nose without being sick, some kind of immune suppression, for example through stress, a diet high in sugar, or low in zinc and selenium?

Get Support from an Integrative Paediatric Health Care Professional

If your child had a sudden onset of anxiety and the standard psychological and supportive measures have not helped, it may be a good idea to have him or her assessed for PANDAS. Not every doctor is familiar with this diagnosis, but immunology and rheumatology specialists generally are. To complicate things even more, not only strep but many other bacteria and even viruses may be able to cause a similar auto-immune reaction with brain inflammation. So if the streptococcal tests are all negative, and you are still suspecting an infectious cause of your child’s acute onset of anxiety, it may be PANS – paediatric autoimmune neuropsychiatric syndrome. I recommend that you find a health professional who will help you find the cause of your child’s anxiety by doing the appropriate tests.

Written by Dr Leila Masson, Paediatrician

Dr Leila Masson is a consultant paediatrician in Bondi Beach, Sydney and the author of

“Children’s Health A-Z” www.drleilamasson.com

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