There is a sectioN under the discussion section where you makr vs threads. Not in manga.
And on paper it seems like madara would win but for some reasons i want to say itachi. Itachi seems like he would find a way through the over powered madara and his ems, rinnegan and wood style.
................On a serious note, as much as clever and strong Itachi is, without rinnegan he would struggle heavily. The ability to switch back and forth from EMS to Rinnegan is just too much.
Itachi has a decent chance with his Sword of Totsuka and Yata Mirror.
I say 70% Madara/30% Itachi winning chance..but Itachi´s 30% are nearly all due his Susano´o with both spiritual items. Without them Itachi would not even have the slightest chance.