Elective surgery often seems to result in Lupus flares. (So does required surgery, of course.) With an auto-immune disease, it just isn't known how or why something might cause a flare, and many kinds of stress are culprits, esp. physical stress. Many of us have flares after surgeries, yet others don't - it's pretty much a guessing game.
Unfortunately, we recently had someone with fairly active lupus pass on shortly after gastric surgery. And we have a member who is having great difficultly after her surgery - issues with not-healing, flares, lung collapse, etc.
I don't off the top of my head know of any lupus patients with gastric bypass who have avoided flares -- but it's possible I simply don't remember the successful surgeries.
It is certainly possible that your surgery was involved in progression of your lupus symptoms -- however, there is no remedy for that and no way to prove or disprove that theory. We have to accept that lupus is a rather tricky and elusive disease, and doesn't have the logical straight forward progression (or remission) that other illnesses might have.
The main things to do, are 1) be sure your rheumy is treating you with a disease-inhibiting medication like plaquenil, and 2) make sure your symptoms are being treated.
Hope you feel better soon,
Lynnwood, Lupus & Sjogren's ModeratorDIAGNOSING-LUPUS & LUPUS-RESOURCES
"Life is far too important to be taken seriously" - Oscar Wilde