 On November 4 , it was confirmed that Lesnar was suffering from mononucleosis and that his bout with Carwin would have to wait a bit longer and the fight for Lesnar 's heavyweight championship was cancelled . On November 14 , at the UFC 105 post @-@ fight conference , Dana White stated , " [ Lesnar ] ' s not well and he 's not going to be getting well anytime soon " and that an interim title match might need to be set up . In addition to mononucleosis , it was revealed that he was suffering from a serious case of diverticulitis , an intestinal disorder , which required surgery . After further diagnosis , Lesnar underwent surgery on November 16 to close a perforation in his intestine that had been leaking fecal matter into his abdomen , causing pain , abscesses , and overtaxing his immune system to the point that he contracted mononucleosis . From the level of damage to Lesnar 's system , the surgeon estimated that the intestinal condition had been ongoing for around a year . 
 On November 4 , it was confirmed that Lesnar was suffering from mononucleosis and that his bout with Carwin would have to wait a bit longer and the fight for Lesnar <a href='null_genetive' title='1'><mark>'s</mark></a>heavyweight championship was cancelled . On November 14 , at the UFC 105 post @-@ fight conference , Dana White<a href='been_done' title='2'><mark></mark></a> stated , " [ Lesnar ] ' s not well and he 's not going to be getting well anytime soon " and that an interim title match might need to be set up . In addition to mononucleosis , it was revealed that he was suffering from a serious case of diverticulitis , an intestinal disorder , which required surgery . After further diagnosis , Lesnar underwent surgery on November 16 to close a perforation in his intestine <a href='null_relcl' title='3'><mark>that</mark></a>had been leaking fecal matter into his abdomen , causing pain , abscesses , and overtaxing his immune system to the point <a href='null_relcl' title='4'><mark>that</mark></a>he contracted mononucleosis . From the level of damage to Lesnar <a href='null_genetive' title='5'><mark>'s</mark></a>system , the surgeon estimated that the intestinal condition had been ongoing for around a year . 
On November 4 , it was confirmed dat Lesnar was suffering from mononucleosis and that his bout with Carwin would gotta wait a bit longer and the fight for Lesnar  heavyweight championship was cancelled . On November 14 , at the UFC 105 post @-@ fight conference , Dana White done stated , " [ Lesnar ] ' s not well and he 's not gnna be getting well anytime soon " and tdatan interim title match might gotta b set up . In addition to mononucleosis , it was revealed that he was suffering from a serious case of diverticulitis , an intestinal disorder , which required surgery . After further diagnosis , Lesnar underwent surgery on November 16 to close a perforation in his intestine had been leaking fecal matter into his abdomen , causing pain , abscesses , and overtaxing his immune system to the point he contracted mononucleosis . From the level of damage to Lesnar  system , the surgeon estimated thdathe intestinal condition had been ongoing for around a year .