Typically, rank adaptation (RA) algorithms are aimed at balancing the trade-off between increasing the spatial gain and improving the interference resilience property. In this paper, we consider a small-cell/local area cellular system and propose a simple and distributed interference-aware rank adaptation algorithm aimed at maximizing the system sum throughput. The performance of the proposed algorithm is numerically evaluated in terms of the system sum throughput. Simulation results show that the proposed algorithm results in close to optimum throughput performance, and can provide up to 40% throughput gain over interference-unaware RA schemes.