Harold Ramis, known best for his portrayal of Egon Spengler in the Ghostbusters films and as the filmmaker behind several beloved comedies, has died at the age of 69. Ramis died due to complications stemming from autoimmune inflammatory vasculitis, a rare disease that he began battling in 2010. The Chicago Tribune reports that Ramis at one point had to relearn to walk as a result of the disease, which involves swelling of the blood vessels. His health again took a turn for the worse when he suffered a relapse of the vasculitis in 2011. Ramis co-wrote the screenplay to Ghostbusters with Dan Akroyd;