Integrating renewable energy in the electricity mix raises several challenges for transmission and distribution system operators. A principal challenge relates to the provision of balancing services from distribution system resources, which requires that the constraints of the distribution network be carefully accounted for when deciding on the dispatch of distribution system resources. In this paper we present a mixed-integer second order cone program for solving a real-time dispatch problem where transmission and distribution are modeled in an integrated fashion. The model offers promising perspectives when tested on real instances of the Italian system.