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Start free with EleplanMixed connective tissue disease
ORPHA:809Disease
Also called MCTD · Sharp syndrome
What it is
Mixed connective tissue disease (MCTD) is a rare connective tissue disorder combining clinical features of systemic lupus erythematosus (SLE), systemic sclerosis (SSc), polymyositis (PM) and/or rheumatoid arthritis (RA).
Key facts
- Prevalence
- 1-9 / 100 000 (Norway)
- Age of onset
- Adolescent, Adult, Childhood
- Inheritance
- Multigenic/multifactorial
- 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
Very common80–99%
12Common30–79%
19- Anti-cyclic citrullinated peptide antibody positivity
- Anti-dsDNA antibody positivity
- Anti-ribosome Po antibody positivity
- Anti-Ro52/TRIM21 antibody positivity
- Anti-U1 ribonucleoprotein antibody positivityDiagnostic criterion
- Arthralgia
- Edema of the dorsum of hands
- Fever
- Increased circulating immunoglobulin concentration
- Joint swelling
- Keratoconjunctivitis sicca
- Myositis
- Pleuritis
- Psychosis
- Raynaud phenomenonDiagnostic criterion
- Rheumatoid factor positive
- Sclerodactyly
- Trigeminal neuralgiaDiagnostic criterion
- Xerostomia
Sometimes5–29%
37- Abnormal EKG
- Abnormality on pulmonary function testing
- Abnormal pulmonary interstitial morphology
- Alopecia
- Anasarca
- Avascular necrosis
- Depression
- Erythema nodosum
and 29 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.
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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