Cigna are calling up the following clinic and hospitals for gastroenterologists for their members in Santo Domingo:
Clinica Corozones Unidos, Naco 809 567 4421
Centro Medico Univ. Centro del Este, Maximo Gomez, 809 221 0171
Cedimat, Plaza de la Salud, Boca Chica, 809 565 9989
Hospital General de la Plaza de la Salud, Av Ortega y Gasset 12, Ensanche La Fe, 809 565 7477 ext 1009
I have no experience of any, hope this helps.