Definition
These are so-called “unclassified” autoinflammatory diseases to date.
The patients present criteria of autoinflammatory diseases after exclusion of the differential diagnoses, however, one cannot determine a disease defined by a set of criteria and there is no mutation found on the possible genetic analyzes carried out by the techniques available at this day.
Epidemiology
It is estimated that there are several hundred patients in France with a so-called “unclassified” autoinflammatory disease to date.
These diseases can affect patients from birth or occur in adulthood. They may concern patients from all over the world.
Genetic
In the autoinflammatory diseases unclassified to date, no mutation is found in a known gene using the genetic sequencing techniques available in the year in which the blood sample was taken.
This does not mean that there is no genetic cause, but rather we are talking about an inconclusive genetic examination currently. Advances in genetics give hope that in the future we will be able to discover new genes responsible for autoinflammatory diseases that have not yet been classified.
Clinical
Unclassified autoinflammatory diseases can affect the whole body, and this is called “systemic”.
In the event of an outbreak of the disease, there are most often general signs such as fever, fatigue and attacks more specific to each patient, in particular rashes, mouth ulcers, diarrhea, abdominal pain, joint or muscle.
Other manifestations may occur depending on the disease such as red eyes, headaches and lymphadenopathy.
Diagnostic
The diagnosis is based on a bundle of clinical arguments, including the presence of inflammation in the crisis blood (elevation of C-reactive protein) and the exclusion of differential diagnoses, in particular infections.
Genetic analysis can be performed to rule out known MONOGENIC autoinflammatory diseases.
The diagnosis of POLYgenic autoinflammatory disease is not retained if the diagnostic criteria are not met.
Evolution
Usually relapses resolve spontaneously over time. However, they regularly recur without treatment.
Certain complications can occur, especially in the absence of effective treatments, and vary according to the patients or the families.
Treatment
The treatment aims to prevent flare-ups and allow a good quality of life without pain and also to prevent disease complications.
Colchicine can be used if it is effective on fever attacks, abdominal pain and inflammation. We sometimes use treatments called biotherapies which are administered by injection.
Since these diseases are "unclassified", in general a treatment is offered that is usually effective in the autoinflammatory disease that most closely matches the patient's symptoms.
Advice from an expert reference center for unclassified autoinflammatory diseases is recommended to optimize diagnostic investigation and treatment, especially since there are advances in these diseases each year.