Undifferentiated connective tissue disease presenting with prevalent interstitial lung disease: case report and review of literature.

Undifferentiated connective tissue diseases (UCTDs) are clinical entities characterised by signs and symptoms suggestive of a systemic autoimmune disease, which do not fulfil the diagnostic criteria for a defined connective tissue disease. Lung involvement can complicate the course and management of the disease, often determining a worse outcome. Respiratory dysfunction as the first clinical manifestation has seldom been reported.We describe a case of a female patient who developed significant respiratory dysfunction as the principal clinical sign. Video-assisted thoracoscopy was performed and a histological pattern of nonspecific interstitial pneumonia (NSIP) was found. A pathological diagnosis suggested careful follow-up with extensive immunological screening which then detected Raynaud's phenomenon and positivity of antinuclear antibodies. After a multidisciplinary discussion (pneumologist, radiologist, pathologist and rheumatologist) a final diagnosis of NSIP associated with UCTD was made. The diagnosis of UCTD should be considered when NSIP is diagnosed even in cases with evident first clinical manifestations of severe respiratory dysfunction. A multidisciplinary approach in the field of interstitial lung disease with NSIP, also including rheumatologic expertise, is fundamental to achieve a prompt and correct diagnosis.