Children with disabilities dapsone side effects acne Van der Sloot was transferred last month from Piedras Gordas penitentiary, on the outskirts of Lima, to the Challapalca prison, which sits at an altitude of 4,800 meters (15,737 feet) in a remote area of southern Peru where temperatures can plunge from 9 C (48 F) in the daytime to minus 20 C (minus 4 F) at night.