PM is an adult disease, usually emerging after the age of twenty. PM and DM are more common in females, more common in Caucasians, and least common in Asians. At any given time, about 35.5 people per million have IBM; it emerges after the age of 30 (usually after 50), and may be more common in males. References


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Mediastinal lymphadenopathy or mediastinal adenopathy is an enlargement of the mediastinal lymph nodes. Causes
There are many possible causes of mediastinal lymphadenopathy, including: 

Tuberculosis
Sarcoidosis
Lung cancer/oesophageal cancer
Lymphangitis carcinomatosa
Cystic fibrosis
Histoplasmosis
Acute lymphoblastic leukemia
Coccidioidomycosis
Lymphoma
Whipples disease
Goodpasture syndrome
Hypersensitivity pneumonitisInflammatory response to Silicone (leaked from ruptured implants) which has migrated and collected in mediastinal lymph nodes. Silicone mediastinal lymphadenopathy. See also
Lymphadenopathy
Mediastinum
Mediastinal lymph node
Mediastinal mass
Neoplasia


== References ==