Canadian Mom - I had excess skin removed from both my arms and inner thighs and never had any problem with infection. There are visible scars, of course, but they're fading nicely. I knew it was a trade-off between skin and scars and am very happy with my decision.
My plastic surgeon told me that a lot of post-WLS patients have trouble with healing and infection because their metabolic systems are compromised and they aren't absorbing all nutrients due to the WLS. In his experience, non-WLS patients heal much faster and with less infection. So that might be an issue to consider.
I know that I healed really
fast and I attribute that to all the protein I eat. Plus my doctor had me start on vitamin C and bioflavonoids before surgery because vitamin C helps with skin healing and growth. As a matter of fact, I still take them because they really did make my skin nice, plus I never get sick now.
If surgery is something you're contemplating, don't hesitate to consult with a plastic surgeon and ask about his/her experiences with infection and scarring. Those are important questions and you want all the reassurance you can get!
Best of luck to you.