From a prospective study starting January 8 to 1990 October 20, the authors discuss 70 cases of acute pneumopathy, supposed to be bacteriologic in patients infected by HIV. The observed pneumopathies are more frequent in young adults, with a pic between 20 to 40 (67.15 p.c). The positivity rate of hemocultures was estimated at 17.14 p.c. with a clear predominance of non typhic Salmonellae. The evolution observed, generally favourable at 72.85 p.c was fatal in 17.15 p.c.