Gut mycobiota dysbiosis and an emergent state of "co-dysbiosis" are associated with IgE sensitization in children with comorbid allergic rhinitis and constipation.

Beta diversity of gut mycobiota was significantly different between ARFC and healthy control children, while alpha diversity was comparable between groups.

• Study included 19 ARFC children and 17 healthy control (HC) children aged 3-6 years
• Metagenomic sequencing was used to characterize gut fungal communities
• Alpha diversity metrics showed no significant differences between ARFC and HC groups
• Beta diversity analysis revealed 'significant structural shifts in the ARFC gut mycobiota'

Key immunomodulatory fungi including Cenococcum, Dentiscutata, Ambispora, and Saccharomyces were markedly depleted in ARFC children compared to healthy controls.

• These four taxa were identified as depleted in the ARFC group relative to HC
• These taxa were described as 'key immunomodulatory fungi'
• The depletion pattern was identified through taxonomic composition analysis
• These fungi were positioned as potentially relevant to gut-immune pathway dysregulation in ARFC

Depleted fungal taxa (Cenococcum, Dentiscutata, Ambispora, and Saccharomyces) served as top discriminators in random forest classification models.

• Random forest models were used to identify taxa that best distinguished ARFC from HC children
• These same four depleted taxa were identified as 'top discriminators' in the random forest models
• This finding supports the biological relevance of the taxonomic differences observed

Depleted fungal taxa exhibited significant inverse correlations with total and allergen-specific IgE levels in ARFC children.

• Cenococcum, Dentiscutata, Ambispora, and Saccharomyces all showed inverse correlations with IgE
• Both total IgE and allergen-specific IgE levels were inversely correlated with these fungal taxa
• The correlations were described as 'significant'
• This positions these fungi as potentially relevant to IgE sensitization mechanisms

Cross-kingdom bacterial-fungal interaction networks showed dramatic ecological restructuring in ARFC, with healthy controls showing competitive interactions while ARFC networks shifted exclusively to positive correlations, a state termed 'co-dysbiosis.'

• Cross-kingdom interaction networks were constructed for both ARFC and HC groups
• HC networks were 'characterized by prevalent competitive interactions' between bacteria and fungi
• ARFC networks 'shifted exclusively to positive correlations'
• The authors coined the term 'co-dysbiosis' to describe this state of cooperative interkingdom interactions
• This represents a novel ecological framing of the bacterial-fungal relationship in allergic-constipation comorbidity

No significant differences were observed in predicted KEGG functional pathways between ARFC and healthy control children.

• Functional potential was predicted using KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis
• Despite structural and taxonomic differences in the mycobiota, functional pathway predictions did not significantly differ
• This dissociation between community structure and predicted function was noted as a finding

This pilot case-control study represents the first characterization of gut mycobiota in children with comorbid allergic rhinitis and functional constipation (ARFC).

• The study enrolled 19 ARFC and 17 HC children aged 3-6 years
• The paper states this provides 'the first evidence that gut mycobiota dysbiosis... is associated with IgE sensitization in ARFC children'
• The study was described as a pilot study
• The authors position the gut mycobiota as 'a novel element of the gut-nose axis in allergic disease'