Missing from the squad is prop BJ Botha who sustained an elbow injury during the second half of last Saturday's home win over Biarritz Olympique. The South African international is due to undergo an operation on Friday.
Speaking at a press conference today, McLaughlin explained: "BJ is having an exploratory operation (on his elbow) on Friday. We'll know more details then.
"It's the ligament. The scan, with the swelling, just wasn't 100% clear. So they've decided that they'll take a look on Friday and see exactly what the problem is.
"If the ligament has to be stitched back on, then they'll do that on Friday as well."
However, hooker and captain Rory Best, who also left the pitch with a rib injury, remains in contention to feature against the Italians.
"Rory threw into the lineouts today. We'll see how he is tomorrow, and take a check then," added McLaughlin.
"He was in a lot of pain. Whatever way it happened, he just got twisted around wrongly and it popped out. The pain dissipated after it popped back in on Sunday.
"We're hopeful that if he comes through the team run and the scrummaging tomorrow, then we'll make a decision after training if there's no reaction."
The rest of the squad is bolstered by the likes of Jamie Smith, Ian Porter, Ryan Caldwell and Thomas Anderson, who played for the Ulster Ravens against Neath last Friday.
A win in Italy this Saturday will see Ulster reach the knockout stages of the Heineken Cup for the first time since the 1998/99 season.
The announcement of the starting line-up and replacements will be made on Friday afternoon.
ULSTER Squad (v Aironi Rugby) - Backs (14): Adam D'Arcy, David McIlwaine, Jamie Smith, Mark McCrea, Andrew Trimble, Simon Danielli, Paddy Wallace, Nevin Spence, Ian Whitten, Ian Humphreys, Niall O'Connor, Ian Porter, Paul Marshall, Ruan Pienaar.
Forwards (18): Tom Court, Declan Fitzpatrick, Jerry Cronin, Bryan Young, Andi Kyriacou, Rory Best, Nigel Brady, Ryan Caldwell, Tim Barker, Dan Tuohy, Johann Muller, Neil McComb, Willie Faloon, Pedrie Wannenburg. Stephen Ferris, Thomas Anderson, Chris Henry, Robbie Diack.