Tomonari Shigemura, Japan

Shinshu University Pediatrics

Presenter of 1 Presentation

Poster Display Other

EARLY-ONSET INFLAMMATORY BOWEL DISEASE IN A PATIENT WITH X-LINKED SEVERE COMBINED IMMUNODEFICIENCY

Lecture Time
10:45 - 10:46
Room
Poster Area
Date
20.09.2019, Friday
Session Time
10:00 - 17:00
Board Number
147
Presentation Topic
Other

Abstract

Background and Aims

Severe combined immunodeficiency (SCID) is a severe defect in differentiation and function of T cells. The most frequent form of SCID is caused by mutations in the X-linked gene IL2RG. Some patients with X-SCID are often followed by enteropathy and failure to thrive, and rarely present with inflammatory bowel disease (IBD) manifestation in the absence of severe infections. However, detailed reports on pathogenesis about X-SCID with IBD manifestation have not been published.

Methods

A 6-month-old boy was referred to our hospital with a 2-month history of intractable diarrhea and recurrent of perianal abscess with fever. No other pathogenic microbes were detected in stools. Colonoscopy revealed multiple longitudinal ulcers from the transverse to the rectal colon, and biopsies demonstrated neutrophil infiltration, proliferative inflammatory granulation tissues, and small granuloma in colon.

Results

Immunological investigation showed hypogammaglobulinemia and mild lymphopenia. DNA sequencing showed a mutation of the IL2RG gene (p.Leu179Argfsx26), which represents T-B+NK- phenotype of SCID in general. However, low number of CD3+ CD4+ T cells had been observed in the peripheral blood and confirmed by identification of maternal T engraftment using microsatellite chimerism. A large number of maternal T cells were infiltrated in colon which was associated with the presence of proliferative inflammatory granulation tissues, and small granuloma.

Conclusions

We proved presence of maternal cells in the intestinal lesions with significant T cell infiltration in spite of a few T cell in the peripheral blood. Therefore, it is likely that these cells are strongly associated with pathogenesis of early-onset IBD in our patient.

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