lupus can represent it self in many ways.
even the one symptom, can show itself in different ways.
lupus can cause the muscles to inflame.
inflames muscles of the bowel can represent itself in two ways.
they can constrict the bowel causing constapation....
or thay can inflame the bowel causing diareah.
so yes constapation can be caused by lupus.
of course it can also be caused by lots of other things.
if constapation is prolonged, please see a doctor, to rule out other possabilities.