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Start free with EleplanHyper-IgM syndrome without susceptibility to opportunistic infections
ORPHA:183666Disease
Also called HIGM without susceptibility to opportunistic infections
What it is
Hyper-IgM syndrome without susceptibility to opportunistic infections is a rare, genetic, primary immunodeficiency due to a defect in adaptive immunity disorder characterized by normal or elevated IgM serum levels with low or absent IgG, IgA and IgE serum concentrations, which manifests with recurrent bacterial sinopulmonary and gastrointestinal infections, with frequent lymphoid hyperplasia (peripheral lymphadenopathy, tonsillar hypertrophy), with no increased susceptibility to opportunistic infections. Autoimmune manifestations (including immune cytopenias, arthritis and hepatitis) are occasionally associated. Immunologic findings reveal absent immunoglobulin class switch recombination and lack of defect of immunoglobulin somatic hypermutations in the presence of normal numbers of CD27+ memory B cells.
Key facts
- Classified as
- Disease
Genes reported in subtypes
Orphanet records these genes on 3 more specific entries under this disorder, not on this entry itself:
A well-studied disease is usually split into subtypes, and the gene is curated on whichever one the evidence belongs to. Open a subtype to see which gene goes with it.
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.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
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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