Inflammatory Bowel Disease in Activated PI3Kδ Syndrome: An Uncommon Complication of a Rare Condition

• Published in: BioMed 2024-11, Vol.4 (4), p.493-498
• Main Authors: Dargenio, Vanessa Nadia, Rutigliano, Vincenzo, Martire, Baldassarre, Pigneur, Bénédicte, Dargenio, Costantino, Francavilla, Ruggiero, Cristofori, Fernanda
• Format: Article
• Language: English
• ISSN: 2673-8430; 2673-8430
• DOI: 10.3390/biomed4040037

Background/Objectives: Monogenic primary immunodeficiencies represent a group of disorders with varying levels of severity, many of which remain poorly understood. Activated phosphoinositide-3 kinase delta syndrome (APDS) is a rare genetic condition resulting from dominant point mutations in the phosphoinositide-3 kinase delta (PI3Kδ) gene, which leads to hyperactivation of the PI3Kδ enzyme, primarily expressed in T and B lymphocytes. Children with this mutation often have recurrent sinopulmonary infections and immunodeficiency. Additional complications may include increased susceptibility to herpes virus infections, lymphoid hyperplasia, and autoimmune conditions. In this case, report, we describe the clinical course of a young boy diagnosed with APDS who developed unclassified inflammatory bowel disease (U-IBD) and explore a personalized treatment approach. Methods: We detail the clinical course of a 12-year-old boy with APDS who presented with fever, diarrhea, anemia, and significant weight loss. Diagnostic evaluations, including endoscopy and histological analysis, led to a diagnosis of U-IBD. Genetic testing confirmed a heterozygous PIK3CD mutation (c.G3061A, p.E1021K). Results: Although APDS is characterized by a broad spectrum of immune dysregulation, the occurrence of IBD in this context is rare. We managed the patient’s IBD with exclusively enteral nutrition to induce remission, followed by a maintenance regimen combining the Crohn’s Disease Exclusion Diet (CDED) and mesalamine, achieving sustained long-term clinical remission. Conclusions: This case underscores the importance of personalized treatment approaches in managing the complex manifestations of APDS.