Unexplained long-lasting…

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Unexplained long-lasting fever/inflammatory syndrome

ORPHA:251332Disease

Also called Persistent fever/inflammation of unknown origin

What it is

A rare systemic disease characterized by febrile illness (body temperature >38.3°C on several occasions) or inflammation (elevated serum C-reactive protein and erythrocyte sedimentation rate) lasting at least three weeks and for which no specific diagnosis is achieved despite extended diagnostics.

Key facts

Age of onset
All ages
Classified as
Disease

ICD-10 codes

R50.8filed under a broader ICD-10 category

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

MONDO 0016666UMLS C5679630

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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