Gastroenterology Associates Category: Clinic About This Location Gastroenterology Associates has temporarily been relocated to Southwest MS Regional Medical Center215 Marion Avenue6th FloorMcComb, MS 39648Please enter through the Main Front Lobby and there will be someone to assist you. Providers at this location Stephen Keith, MDJoseph A. Richard, CFNPMichelle Thomas, CFNPMary Thornton, CFNP Our Services Gastroenterology Search for services at other locations: Select a Service GastroenterologyMaternity SuitesWomen's Care Search