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Start free with EleplanLangerhans cell histiocytosis
ORPHA:389Disease
Also called Histiocytosis X · Langerhans cell granulomatosis
What it is
A rare systemic disease characterized by the accumulation (usually organized in granulomas) of macrophage, bearing the features of Langerhans cells in various tissues.
Key facts
- Prevalence
- 1-9 / 100 000 (Europe)
- Age of onset
- All ages
- Inheritance
- Unknown
- 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.
Signs and symptoms
Sometimes5–29%
15- Ataxia
- Diabetes insipidus
- Dysarthria
- Genital ulcers
- Growth delay
- Hearing impairment
- Hypoalbuminemia
- Leukopenia
and 7 more in this range
These 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.
Genes
Genes reported in subtypes
Orphanet records this gene on 4 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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