New Paper in Neurology

[T_Mom]

In the October 20th issue of Neurology, there is a new retrospective study entitled "Streptococcal infection, Tourette syndrome, and OCD: Is there a connection?" http://www.neurology.org/cgi/reprint/73/16/1256

 

The paper is a UK study paralleling the work by Mell in 2005 "Association between streptococcal infection and obsessive-compulsive disorders, Tourette's syndrome, and tic disorder" http://pediatrics.aappublications.org/cgi/reprint/116/1/56

 

The new paper looked at the coding records of 678,862 patients selecting 4784 patients for the study. The subset was selected by looking for OCD/Tourette's diagnosis and then matching for age. It seemed odd that a pediatrician would diagnose OCD (a psychiatric disorder) rather than referring the child to a psychiatrist, but that's what the study found.

 

In any case, they isolating 129 cases of OCD and 126 cases of TS/tics and used 2211 age-matched controls for OCD and 2308 age-matched controls for TS/tics. Curiously the study found only 22 of the OCD cases had onset < 10 yrs old. The majority of cases (71) had onset > 16.

 

This meant that they found the overall incidence of OCD to be 1:5000, and for children < 10 to be 1:33,000.

 

What was also strange was that only 20 of the OCD or tic cases had a preceding strep infection within the last 2 years. 9 of these cases were not treated and 11 were treated with antibiotics.

 

The study concludes that the data does "not support a strong relationship between streptococcal infections and neuropsychiatric syndromes" however, it did note with caution that incidences of OCD were more likely to have had an untreated possible strep infection (i.e., no antibiotics were prescribed).

 

What I found amazing about the whole study was that in looking at 685 cases of likely strep over a 5 year period, there were only 67 throat swabs and only 6 ASO titers. Thus in > 90% of cases, strep throat was being diagnosed by clinical signs. If the sample on this forum is any indiction, there was probably a lot of undiagnosed strep.

 

 

I'm not sure what to make of the study at this point. It did not look at suddenness of onset, did not apparently look for multiple strep infections, did not look at remission of symptoms. It is impossible to tell if the presented cases differ from traditional OCD. If we assume that the <5% of traditional OCD cases are actually PANDAS, then the study is underpowered and no PANDAS children were likely found.

 

Kurlan and Gilbert have commentary about PANDAS and SC in the same issue but don't really help any (particularly as they fail to acknowledge the finding of higher incidence for untreated strep).

 

Buster

[kim]

Two clinical notes should be made. First, not all

symptom exacerbations were preceded by GABHS infections;

viral infections or other illnesses could also

trigger symptom exacerbations. This is in keeping with

the known models of immune responsivity—primary

responses are specific (e.g., directed against a particular

epitope on the GABHS), while secondary responses

are more generalized. Thus, the lack of evidence for a

preceding strep infection in a particular episode does

not preclude the diagnosis of PANDAS.

 

 

Thanks EAMom. I knew Buster had a thread summerizing findings but I couldn't find it. Located it under the stickies this morning, but thanks for you excerpt anyway!

 

Here is a link to the thread that I was looking for, if anyone else wants to review

http://www.latitudes.org/forums/index.php?...amp;#entry36300

 

Meg's mom, good idea. It seems quite ironic that we couldn't get "not positive" strep cultures for such a long stretch when the boys were younger. I was/am still struggling with the "abrupt onset," criteria. The saving sammy presentation is NOT what we experienced. The "sneezing" little girl, looks a lot closer, if you substitute her tic with head shaking, or other tics. It seems obvious that there are different degrees or maybe totally different things going on here, but overlap too. At any rate, it's good to see research moving forward

[Buster]

We cite the same article but try to provide the simple bulleted list:

• 46% of culture positive children do not have an ASO rise
  
• 54% of culture positive children do not have anti-DNAseB
  
• Contrary to popular opinion, the combination of ASO and Anti-DNAse-B failed to confirm GABHS in 31% of culture positive children.
  

If they bring up carriage, I ask if they mean asymptomatic or symptomatic carriage.

 

The AMA recommends treatment of any symptomatic carriage to prevent dangers of ARF.

 

The estimated asymptomatic carriage rate is estimated as being ~8-10% by WHO, there is no explanation yet widely accepted for this carriage.

 

The asymptomatic cases are treated when there is either prior RF, SC, Kawasaki or one in the household. Asymptomatic carriage is still contageous but just less so than symptomatic carriage. This is why siblings are often treated. With respect to PANDAS and GABHS carriers -- this is not studied.

 

 

Buster

 

 

 

 

 

 

We also observed that, although 136 (67%) of 202

children showed a significant increase in anti-SCPA, only 109

(54%) showed a significant increase in ASO, 91 (45%) in anti–

DNase B, and 127 (63%) in either ASO and/or anti–DNase B

(figure 6). When the 3 antibodies are compared (ASO, anti–

DNase B, or anti-SCPA), the percentage of children showing

an increase in any of these titers was 69%, which is not appreciably

different from the proportion showing a significant

increase in anti-SCPA alone.