The Coventry outfit, who have already lost fly-half Danny Cipriani to a knee injury, saw Hughes forced off at the Ricoh Arena during the defeat at the weekend.
Wasps director of rugby Dai Young has since admitted Hughes may miss the encounter Saracens on Sunday.
"Nathan had quite a bad dead leg," he said. "Hopefully he will recover by next week, but we don't know.
"We've said before it will only be one week and it ends up being longer.
"We said that with Danny Cipriani - one week to 10 days when it was three months, so what do I know?
"It's a bit early to tell, but he's certainly not looking at knee instability or anything like that, it's purely a dead leg. Nathan's a big player for us."
The news will come as a concern for England head coach Eddie Jones, with fellow No.8 Billy Vunipola already ruled out of the autumn internationals against Argentina, Australia and Samoa.