Experimental data indicate that bacterial L-forms drastically change not only their morphology but also their life style in vivo - long persistence outside or inside the phagocyte cell due to the ineffectual phagocytosis, digestion and clearance of L-forms. Experimental L-form infections are modified - less intensive, appear later and remain longer than those provoked by the respective parental bacterial form.
L-form conversion might be considered as a phenomenon of adaptation when bacteria are exposed to different damaging factors, particularly in face of host defense mechanisms. It arises along with resistance to these factors and facilitates the bacterial survival and persistence in vivo.
The arguments for or against their significance as infecting agents are limited by difficulties in microbiological determination, cultivation and identification of L-forms. They could be associated with latent, chronic, and relapsing infections, as well as with diseases of unknown infectious-allergic or autoimmune origin.
