This will come as no surprise to those parents out there who have dealt with the nightmare symptoms of PANS or PANDAS in their children. Researchers in Rome collected stool samples from 30 patients with PANS/PANDAS, aged 4-16 years old, and compared them to 70 unaffected normal peers.[i] “An altered bacterial community structure was detected in PANS/PANDAS patients when compared to controls.”[ii] All the affected children had lower levels of bacterial diversity than did their typical peers.
They found that the younger group of children (aged 4-8) had a more limited loss of biodiversity. In this group, they found a reduction of the Firmicutes species and a significant increase in Bacteroidetes. Just such an altered ratio has been associated with metabolic disorders like obesity. They also found, in the younger group, a decrease in anti-inflammatory short chain fatty acids and other important anti-inflammatory elements.
The older group of children (9-16) had a less uniform bacterial profile and showed no consistent distinct biomarkers. The researchers explained this by pointing out that these older children would have had a much greater exposure over time to antibiotic, which is a first-line treatment for PANS/PANDAS.
Two more interesting findings:
- The control children had higher levels of Roseburia genus members, which helps preserve gut barrier function and produces the highly anti-inflammatory butyrate (a short chain fatty acid).
- The researchers noted that in children with very high strep antibodies (an ASO over 500), there is a significant correlation with bacterial alterations: “…these data suggest that streptococcal influence may influence gut microbiota composition and host inflammation, contributing to the development of disease.”
Apparently, then, the presence of strep causes alterations in the bacterial microbiome which, in turn, lead to high levels of inflammation. The article does not, unfortunately, explain why some children are more susceptible to this effect from strep, which is a pretty common illness. I wonder if there’s any correlation to early antibiotic use before the first symptoms appear?
[i] Quagliariello A, Del Chierico F, Russo A, et al. Gut microbiota profiling and gut-brain crosstalk in children affected by pediatric acute-onset neuropsychiatric syndrome and pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections. Front Microbiol. 2018. doi: 10.3389/fmicb.2018.00675.