AUTHOR=Mettman Daniel , Thiffault Isabelle , Dinakar Chitra , Saunders Carol 

TITLE=Immunodeficiency-Associated Lymphoid Hyperplasia As a Cause of Intussusception in a Case of Activated PI3K-δ Syndrome

JOURNAL=Frontiers in Pediatrics

VOLUME=5

YEAR=2017

URL=https://www.frontiersin.org/journals/pediatrics/articles/10.3389/fped.2017.00071

DOI=10.3389/fped.2017.00071

ISSN=2296-2360

ABSTRACT=<p>Activated PI3K-δ syndrome refers to a recently described primary immunodeficiency syndrome consisting of recurrent sinopulmonary infections, lymphadenopathy, mucosal lymphoid aggregates, increased susceptibility to Epstein–Barr virus and cytomegalovirus, and increased incidence of B-cell lymphomas. Variants in <italic>PIK3CD</italic>, which encodes the phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit delta isoform, enhance membrane association and kinase activity, resulting in increased signal transduction through the PI3K–Akt pathway. Whole-exome sequencing revealed a pathogenic <italic>PIK3CD</italic> variant in a patient with history of immunologic impairment, recurrent sinopulmonary infections, and lymphoid hyperplasia presenting as intussusception. This case illustrates that while lymphoid hyperplasia secondary to immunodeficiency is most often unsurprising and non-threatening, it can present as an emergency-like intussusception.</p>