Hogg was forced off after 15 minutes following a collision with Ireland loose-forward Peter O'Mahony, with reports on Wednesday suggesting he would miss the remainder of the Six Nations.
"Well, it's news to me that he's out for the Six Nations as we're still waiting to see how he recovers," Townsend told reporters.
"He's about to see a specialist, so we'll know more about his chances of playing over the next few weeks after that. I'm very hopeful that he'll get good news and that he'll be available to play some part in the Six Nations."
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Townsend had praise for Hogg’s replacement Blair Kinghorn, as well as the depth in his squad in the back three division.
"Blair obviously had a great game against Italy. He backed that up on his first touch as he got through the Ireland defence on Saturday and being heavily involved in the second half.
"We've got good strength and depth in the back three. We've got Darcy Graham, who has been playing really well for Edinburgh. Tommy Seymour and Sean Maitland have both played at full back and are both very experienced players.
"I believe Byron McGuigan is back for his club (Sale Sharks) this week, so if Stuart is missing – and I really hope that's not the case – then we do have other players who have played international rugby and are in really good form."
Scotland are next in action against France in Paris on Feb. 23. They beat Italy 33-20 in their opener earlier this month.
(Reporting by Nick Said; Editing by Ken Ferris)
