Patients presenting with connective tissue disease symptoms with positive serology, clinical physical findings compatible with connective tissue disease but not fulfilling the specific criteria for one of the established diagnoses defines this process
Connective tissue diseases (CYDs) or characterized by damage caused by autoimmunity in multiple organs including the skin, joints, heart, lungs, and kidneys..
They comprise seven clinical entities: rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, primary Sjogren syndrome, dermatomyositis/polymyositis and its related anti-synthetase syndrome, mixed connective tissue disease, and undifferentiated connective tissue disease.
There is x-ray prevalence of subclinical interstitial lung disease in 33-57% of CTD.
Up to 90% of patients with systemic sclerosis have radiologic features of interstitial lung disease on high-resolution CT and has the highest prevalence, followed by those of dermatomyositis/polymyositis 20-78%, and rheumatoid arthritis 6.5-33%.
The process includes patients with signs and symptoms of a connective tissue disease with positive antinuclear antibody studies and persists for at leas 3 years (Mosca)..
Probably a common process but no sufficient data exists as to its frequency.
Most patients who do not progress in the first year of follow-up to a specific diagnostic connective tissue disease remain in this undifferentiated category.
Almost all patients that progress to a specific connective tissue disease do so by 24 months.overall survival rates for this process are better than for those patients with specific diagnosis for a connective tissue disease.
Patients with early undifferentiated process that go on to a specific diagnostic process have a better prognosis than those who are diagnosed with the specific type of disease from the onset.
Associated morbidity and mortality related to extent of organ involvement.
Female predominance and probably more common in Caucasians.
Onset most common in middle age.
Interstitial lung disease may occur as the only manifestations of undiagnosed connective tissue disease.
Often connective tissue disease-interstitial lung disease have a better prognosis than other non-autoimmune related fibrotic lung diseases such as idiopathic pulmonary fibrosis, but may also have a poor course poorer course tham other connective tissue diseases without interstitial lung disease.
Therapies for connective tissue disease related interstitial lung disease range from the immunosuppressive agents corticosteroids to corticosteroid sparing agents and biological agents, as well as anti-fibfrotic agenyptd and therapies such as hematopoetic stem cell transplant.
Immunosuppression is the mainstay of treatment and is used in progressive cases of those with multi organ involvement. More aggressive immunosuppressive agents, such as cyclophosphamide and rituximab are reserve for refractory, severe or rapidly progressive disease states.
