By Mitch Phillips LONDON, Oct 3 (Reuters) - Double Olympic triathlon champion Alistair Brownlee was among the latest batch of athletes to have their therapeutic use exemptions (TUEs) leaked on Monday, with the Briton explaining the drug he used in 2013 was to treat altitude sickness. In the sixth tranche of personal records released by hackers at the group called Fancy Bears, Brownlee was revealed to have used acetazolamide, banned by WADA, on Oct. 10 and 11 2013, having been given an exemption by UK anti-doping. Brownlee said last week that he had one TUE for the drug after suffering altitude sickness while climbing Kilimanjaro and reconfirmed that in a tweet on Monday. More...