Acinetobacter spp was detected around the 20th century by famous bacteriologist Beijerinck, but it was not until 1960 that A.baumannii was declared in hospital. Belongs to the large family of non-fermentable gram-negative bacteria capable of harming patients in surgical intensive care . During the 20 past years it has developed a capital importance and its classification among the nosocomial infections makes it a priority to all the public health organizations considering its increase and recurrence. A.baumannii is much more present in humans and is the origins of multiple diseases like septic fever, pneumonitis pachymeningitis and other disease. Over time it has gained its resistance through diverse modifications and is presently resistant to approximately all the various groups of antibiotics even the most widely used drugs (fluoroquinolones, macrolides, trimethoprim, b-lactams, tetracyclines, aminoglycosides, and chloramphenicol). Нe bacterial efflux operation causes the formation of toxins and rejects antibiotics from the cells, which confers a specific invulnerability to antibiotics. Multidrug resistant (MDR) efflux pumps are now present in almost all microorganisms, in which bacteria it is one of the main causes of obstruction to action of drugs; several works have concluded that MDR is on origin of the decline progressive of drugs sensitization by bacterial mutation that reduce largely the valid drug for cure.