soft markers after anatomy ultrasound

Has anyone had soft markers for exogenic bowel at their anatomy ultrasound? We are currently waiting on blood test results to rule out infections, Downs Syndrome and Cystic fibrosis after his diagnosis at 19 weeks. And we are having another ultrasound at 28 weeks. Has anyone else been through this? If all of your results came back negative- then what did your dr say? Are there any further concerns for the baby? Thanks