Drs. Nelson P. Trujillo and Donald O’Kieffe established a Gastroenterology practice in the Washington, D.C., area in the 1960s. In 1985, they were joined in partnership by Michael Weinstein, M.D. Although office endoscopy was being performed at their practice, they decided to expand into a formal facility because of the limited access and increasing cost of out-patient hospital facilities. The Abdominal Pain and Endoscopy Center was licensed in the District of Columbia and received Medicare certification in 1986. The mission of the center was to provide high-quality endoscopic services in the most appropriate and cost effective setting.

The practice also continued to grow and with the addition of Louis Korman, M.D. The center experienced rapid growth as well and moved to a larger space at 2021 K Street, N.W. in Washington, D.C., in 1992. In November 1993, the center formed a limited partnership with AmSurg Corporation in Nashville, Tenn., to jointly manage the renamed Endoscopy Center of Washington, D.C.