AJ'S DEATH IS RULED A HOMICIDE!

TMZ has learned the death of "Real Housewives of Atlanta" star A.J. Jewell has officially been ruled a homicide -- this according to the Fulton County Medical Examiner.
The cause of death is listed as, "Physical altercation resulting in sickle cell trait related exertional collapse." Contributing factors are listed as, "intestinal myocardial fidrosis," as well as an enlarged heart.

Translation -- the fight triggered a flare up with Jewell's sickle cell disease.

Jewell died after an Atlanta strip club brawl early last month. The other man involved in the fight -- Frederick Richardson -- has since been arrested and charged with voluntary manslaughter.

Richardson's attorney tells us, "It's an unfortunate situation, Frederick is sorry this situation happened and that A.J. died."