Logically, since Lupus is a disease that causes inflammation in the body's tissues and organs...and an enlarged gall bladder can be caused by inflammation ((cholecystitis - an acute or chronic inflammation of the gallbladder ) it would stand to reason that Lupus can have something to do with your enlarged gall bladder. There have been cases of acute cholecystitis due to vasculitis of the gall bladder in people with systemic lupus erythematosus.
Also, Lupus is a "connective tissue" disease and one of the important parts of the gall bladder is the function of its connective tissue (The gallbladder has a simple columnar epithelial lining characterized by recesses called Aschoff's recesses, which are pouches inside the lining. Under the epithelium there is a layer of connective tissue (lamina propria). Beneath the connective tissue is a wall of smooth muscle (muscularis muscosa) that contracts in response to cholecystokinin, a peptide hormone secreted by the duodenum. There is essentially no submucosa separating the connective tissue from serosa and adventitia.). So, there apparently is an association between Lupus and enlarged gall bladder!
I hope this helped
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