外排泵的过表达是目前导致鲍曼不动杆菌多重耐药的最重要机制之一，详细了解这一复杂机制有助于尽快找到有效的防治策略。目前，鲍曼不动杆菌中已被报道的外排泵家族包括耐药结节细胞分化(resistance-nodulation-cell division，RND)家族、主要协同转运蛋白超家族(major facilitator superfamily，MFS)、多药及毒性化合物外排(multidrug and toxic compound extrusion，MATE)家族、小多重耐药(small multidrug resistance，SMR)家族。它们之中既有通过染色体介导的外排泵，也有通过质粒等遗传元件介导的外排泵。外排底物可呈现多样性，也可呈现专一性。本文就上述外排泵的种类、功能和调控机制进行综述。

The overexpression of efflux pump is one of the most important multidrug-resistant mechanisms in Acinetobacter baumannii (A. baumannii). The understanding of their complicated mechanisms will help to find out efficient coping strategy. So far four prominent families of efflux transporters in A. baumannii have been reported, including resistance-nodulation-cell division (RND) superfamily, major facilitator superfamily (MFS), multidrug and toxic compound extrusion (MATE) superfamily, and small multidrug resistance (SMR) superfamily. They can be divided into chromosomally encoded efflux system and acquired efflux system. The substrates are also distinguished among different efflux transporters. In this review, the classification, function and regulation of efflux pumps in A. baumannii are described.