Clinical and immunologic phenotype associated with activated phosphoinositide 3-kinase δ syndrome 2: A cohort study
- J Allergy Clin Immunol. 2016 Jul;138(1):210-218.e9. doi: 10.1016/j.jaci.2016.03.022.
- 1. Department of Pediatric Immunology, Hematology and Rheumatology, AP-HP, Necker Children's Hospital, Paris, France; INSERM UMR1163, Paris, France.
- 2. Department of Pediatric Immunology, Hematology and Rheumatology, AP-HP, Necker Children's Hospital, Paris, France; INSERM UMR1163, Paris, France; Université Paris Descartes-Sorbonne Paris Cité, Institut Imagine, Paris, France.
- 3. Université Paris Descartes-Sorbonne Paris Cité, Institut Imagine, Paris, France; Department of Pathology, Hôpital Necker-Enfants Malades, Assistance Publique des Hôpitaux de Paris, Paris, France.
- 4. Department of Pediatrics, National Defense Medical College, Saitama, Japan.
- 5. Départment de Biothérapie, Centre d'Investigation Clinique intégré en Biothérapies, Necker Children's Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France.
- 6. INSERM UMR1163, Paris, France; Université Paris Descartes-Sorbonne Paris Cité, Institut Imagine, Paris, France.
- 7. Laboratory of Immunology, Molecular Development of the Immune System Section, NIAID Clinical Genomics Program, NIAID, NIH, Bethesda, Md.
- 8. Belarusian Research Center for Pediatric Oncology, Hematology and Immunology, Minsk, Belarus.
- 9. Department of Medicine, University of Cambridge, Cambridge, United Kingdom.
- 10. Division of Immunology, University Children's Hospital Zurich, Children's Research Center, Competence Center for Applied Biotechnology and Molecular Medicine and the Swiss Center for Regenerative Medicine, University Zurich, Zurich, Switzerland.
- 11. Service de Pédiatrie, Centre Hospitalier Annecy Genevois, Metz-Tessy, France.
- 12. Centre for Genomic & Experimental Medicine, Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom.
- 13. Department of Clinical Immunology and Allergy, St James's University Hospital, Leeds, United Kingdom.
- 14. Nottingham University Hospitals, Nottingham, United Kingdom.
- 15. Pediatric Immunology Division, Uludag University Medical Faculty, Department of Pediatrics, Bursa, Turkey.
- 16. Department of Pediatrics and Developmental Biology, School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
- 17. Oncological Practice Oldenburg/Delmenhorst, Oldenburg, Germany.
- 18. Institute of Cellular Medicine, Paediatric Immunology Department, Great North Children's Hospital, Newcastle upon Tyne, United Kingdom.
- 19. Department of Immunology, School of Medicine, Trinity College Dublin, St James's Hospital, Dublin, Ireland; Department of Pediatric Immunology and Infectious Diseases, Our Lady's Children's Hospital Crumlin, Dublin, Ireland.
- 20. Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy.
- 21. Department of Pediatric, Hôpital Nord, Saint-Etienne, France.
- 22. Pediatrics Clinic and Institute for Molecular Medicine A. Nocivelli, Department of Clinical and Experimental Sciences, University of Brescia, Spedali Civili di Brescia, Brescia, Italy.
- 23. Children's Hospital, Skåne University Hospital, Lund, Sweden.
- 24. Service d'Hématologie Pédiatrique, Marseille, France.
- 25. Department of Pediatrics, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan.
- 26. Clinical Immunology Department, Hôpital Saint Louis, Assistance Publique Hôpitaux de Paris, Université Paris Diderot, Paris, France.
- 27. Department of Pediatrics, National Defense Medical College, Saitama, Japan; Department of Pediatrics, Tokyo Medical and Dental University, Tokyo, Japan.
- 28. INSERM UMR1163, Paris, France; Université Paris Descartes-Sorbonne Paris Cité, Institut Imagine, Paris, France; Study Center for Primary Immunodeficiencies, Assistance Publique Hôpitaux de Paris, Necker Hospital, Paris, France.
- 29. Centre for Genomic & Experimental Medicine, Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom; National Institute for Health Research-Leeds Musculoskeletal Biomedical Research Unit (NIHR-LMBRU) and Leeds Institute of Rheumatic and Musculoskeletal Medicine (LIRMM), St James's University Hospital, Leeds, United Kingdom.
- 30. INSERM UMR1163, Paris, France; Université Paris Descartes-Sorbonne Paris Cité, Institut Imagine, Paris, France; Départment de Biothérapie, Centre d'Investigation Clinique intégré en Biothérapies, Necker Children's Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France.
- 31. Department of Pediatric Immunology, Hematology and Rheumatology, AP-HP, Necker Children's Hospital, Paris, France; INSERM UMR1163, Paris, France; Université Paris Descartes-Sorbonne Paris Cité, Institut Imagine, Paris, France; Collège de France, Paris, France.
- 32. INSERM UMR1163, Paris, France; Université Paris Descartes-Sorbonne Paris Cité, Institut Imagine, Paris, France. Electronic address: [email protected].
Background: Activated phosphoinositide 3-kinase δ syndrome (APDS) 2 (p110δ-activating mutations causing senescent T cells, lymphadenopathy, and immunodeficiency [PASLI]-R1), a recently described primary immunodeficiency, results from autosomal dominant mutations in PIK3R1, the gene encoding the regulatory subunit (p85α, p55α, and p50α) of class IA phosphoinositide 3-kinases.
Objectives: We sought to review the clinical, immunologic, and histopathologic phenotypes of APDS2 in a genetically defined international patient cohort.
Methods: The medical and biological records of 36 patients with genetically diagnosed APDS2 were collected and reviewed.
Results: Mutations within splice acceptor and donor sites of exon 11 of the PIK3R1 gene lead to APDS2. Recurrent upper respiratory tract infections (100%), pneumonitis (71%), and chronic lymphoproliferation (89%, including adenopathy [75%], splenomegaly [43%], and upper respiratory tract lymphoid hyperplasia [48%]) were the most common features. Growth retardation was frequently noticed (45%). Other complications were mild neurodevelopmental delay (31%); malignant diseases (28%), most of them being B-cell lymphomas; autoimmunity (17%); bronchiectasis (18%); and chronic diarrhea (24%). Decreased serum IgA and IgG levels (87%), increased IgM levels (58%), B-cell lymphopenia (88%) associated with an increased frequency of transitional B cells (93%), and decreased numbers of naive CD4 and naive CD8 cells but increased numbers of CD8 effector/memory T cells were predominant immunologic features. The majority of patients (89%) received immunoglobulin replacement; 3 patients were treated with rituximab, and 6 were treated with rapamycin initiated after diagnosis of APDS2. Five patients died from APDS2-related complications.
Conclusion: APDS2 is a combined immunodeficiency with a variable clinical phenotype. Complications are frequent, such as severe Bacterial and viral infections, lymphoproliferation, and lymphoma similar to APDS1/PASLI-CD. Immunoglobulin replacement therapy, rapamycin, and, likely in the near future, selective phosphoinositide 3-kinase δ inhibitors are possible treatment options.