[Role of persistence characteristics of microorganisms in pathogenesis of endogenous infections]. 
Definition of endogenous bacterial infections (EBI) is formulated as well as their nosological variability is demonstrated and clinical and microbiological characteristics are characterized.  Universal scheme of pathogenesis of these infections with separation of key phases of their course: premorbid phase, colonization, alteration, sanation or persistence.  Important role of persistence characteristics of microorganisms for the development of EBI, which provide survival of agents during contacts with humoral and cellular effectors of host's immunity, is substantiated.