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Start free with EleplanX-linked lymphoproliferative disease due to SAP deficiency
ORPHA:538931Disease
Also called X-linked lymphoproliferative disease due to Signaling lymphocyte activation molecule-associated protein deficiency · X-linked lymphoproliferative syndrome type 1 · XLP1 · X-linked lymphoproliferative disease due to SH2 domain containing 1A protein deficiency · X-linked lymphoproliferative disease due to SH2D1A deficiency
What it is
A rare, genetic, primary immunodeficiency disorder characterized by an abnormal immune response to Epstein-Barr virus (EBV) infection, caused by hemizygous mutations in the X-linked SH2D1A gene, resulting in B cell lymphoproliferation and manifesting with various phenotypes which include EBV-driven severe or fulminant mononucleosis, hemophagocytic lymphohistiocytosis (presenting with fulminant hepatitis, hepatic necrosis, bone marrow hypoplasia, and neurological involvement), hypogammaglobulinemia, and B-cell lymphoma. Additional variable manifestations include vasculitis, lymphomatoid granulomatosis, aplastic anemia, and chronic gastritis. Occasionally, T-cell lymphoma may be observed. Laboratory findings include normal or increased activated T cells and reduced memory B cells.
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Adolescent, Adult, Childhood, Infancy
- Inheritance
- X-linked recessive
- Classified as
- Disease
Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.
Gene
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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