The 19-year-old had been transferred to a Vienna hospital on November 7, after a week of treatment in Bucharest.
Another 40 people remain in hospital in Romania with injuries suffered in the fire that raged through a basement club in the capital on October 30. 28 others have been flown abroad for treatment.
The ill-fated nightclub was packed with some 400 revellers attending a rock concert when fireworks were let off, triggering a blaze and stampede. 26 people died on the spot and nearly 200 were injured.
The venue's three owners are have been charged with manslaughter.
The tragedy sparked mass anti-government protests, which led to the resignation of prime minister Victor Ponta, who had already been under pressure to quit over allegations of tax evasion and money-laundering.
He has been replaced by former EU agriculture commissioner Dacian Ciolos.