[The pathophysiology and immune response to broncho-pulmonary bacterial infections (author's transl)].

This study is in two parts. The first is devoted to a brief reminder of those situations in which pathogenic microbes invade the respiratory tract and is concerned with: the rapid elimination of the pathogen, thanks to the intervention of the first line of defence of the lung; a delayed elimination which sets in action complementary mechanisms inducing an inflammatory response; the overflow of the defence system with the development of the infectious illness. The second part is devoted to a review of the causes of failure of the defence mechanisms against the microbes. Two series of events are discussed: first constitutional immune deficiency and secondly acquired deficiencies.