Objective:

To describe a unique case of Autoinflammation with Infantile Enterocolitis (AIFEC) caused by a novel mutation in the NLRC4 gene and to review existing literature on the condition.

Approach:

• Case Presentation: A 2-year-and-4-month-old female presented with recurrent fever, chronic diarrhea, mucous bloody stools, and multi-system involvement. Laboratory investigations revealed significantly elevated inflammatory markers, and endoscopy showed multiple ulcers in the ileocolonic region. Whole-exome sequencing identified a de novo heterozygous mutation c.167A > G (p.His56Arg) in the CARD domain of NLRC4, validated by Sanger sequencing and functionally assessed for pathogenicity.

Key Findings:

• A novel heterozygous mutation c.167A > G (p.His56Arg) in the CARD domain of NLRC4 was identified, validated by Sanger sequencing and functionally assessed for pathogenicity.
• The patient achieved clinical remission following infliximab treatment.
• This case expands the known mutational and phenotypic spectrum of AIFEC.

Interpretation:

The findings suggest that mutations in the CARD domain of NLRC4 may lead to distinct clinical presentations and that infliximab could be a potential therapeutic option for AIFEC.

Limitations:

• The case report is based on a single patient, limiting generalizability.
• The mutation identified has not been previously reported, necessitating further validation.

Conclusion:

This case highlights a novel NLRC4 variant associated with AIFEC and suggests the potential utility of infliximab as a targeted therapy.