In one sentence
A sibling-controlled study found that three key inflammatory proteins in stool were not significantly different between autistic children and their non-autistic biological siblings — suggesting some earlier “gut inflammation in autism” findings may partly reflect shared family and environment rather than autism alone.
What the researchers did
Researchers compared alpha-1-antitrypsin (A1AT), immunoglobulin A (IgA), and calprotectin in stool from 57 autistic children (48 boys, 9 girls) and 57 biological siblings without autism (29 boys, 28 girls). Matching siblings helps control shared genetics and home environment. Children were recruited from a university autism centre in Slovenia (2016–2020). Proteins were measured with high-precision laboratory methods. Exploratory analyses also looked at autism severity on the Childhood Autism Rating Scale (CARS). Children with recent antibiotics or active gastrointestinal symptoms were excluded.
What they found
- Overall, none of the three main markers differed statistically between autistic children and their siblings.
- Small trends (slightly higher IgA and calprotectin, slightly lower A1AT in the autism group) could have been chance findings.
- In very small exploratory subgroups, moderate autism showed higher IgA versus siblings, and severe autism (11 pairs) showed an altered calprotectin subunit ratio — treated by the authors as hypothesis-generating, not conclusive.
What this means for families and therapists
- Routine stool testing of these markers is unlikely to diagnose autism or guide autism-specific treatment for most children.
- Gastrointestinal symptoms in an autistic child still deserve ordinary medical work-up; this study does not say gut problems are imaginary.
- Be cautious with commercial “inflammation panels” marketed as autism explanations when sibling-controlled evidence is null for these markers.
Limitations and what we don't know yet
- Sample of 57 pairs; sex balance differed between groups.
- Severity subgroups were underpowered (especially 11 severe pairs).
- Children with current GI symptoms were excluded, so results may not apply to that clinical subgroup.
- Single-centre study; larger, more diverse replications are needed.
This is a plain-language summary of Faecal inflammatory protein markers in children with autism spectrum disorder are comparable to their healthy siblings by Osredkar J., Finderle P., Godnov U. et al., Frontiers in Psychiatry (2026). Source license: CC-BY-4.0. It is not medical advice — talk to a qualified clinician before changing therapy.