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Start free with EleplanIgG4-related pachymeningitis
ORPHA:449427Clinical subtype
Also called Idiopathic hypertrophic pachymeningitis
What it is
A rare, brain inflammatory disease characterized by thickening of the dura mater of the cranium or spine with at least two histiopatholgical features of IgG4-related disease: dense lymphoplasmacytic infiltrate, storiform fibrosis, and/or obliterative phlebitis. Patients typically have non-specific CSF findings, and might be without systemic involvement or serum IgG4 elevation. Clinical manifestation are caused by mechanical compression of nerve or vascular structure, leading to functional deficit, most commonly headache, cranial nerve palsies, vision problems and motor weakness.
Key facts
- Age of onset
- Adult, Elderly
- Inheritance
- Not applicable
- Classified as
- Clinical subtype
Signs and symptoms
Common30–79%
6These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
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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