[Surface characteristics and antimicrobial sensitivity of clinical strains of Acinetobacter spp]

The treatment of nosocomial infections caused by Acinetobacter baumannii has been hindered by the easiness of this species to acquire antimicrobial resistance.

To study surface hydrophobicity, the presence of capsule and antimicrobial susceptibility of nosocomial Acinetobacter spp strains.

Ninety four Acinetobacter spp strains isolated from a public hospital of Santiago, between July 1995 and April 1996, were studied.

Compared to Acinetobacter genospecies 3 isolates, A baumannii isolates exhibited greater antimicrobial resistance, was uniformly susceptible to imipenem and highly resistant to other antimicrobials of clinical use. Most strains of biotypes 8 and 9 were hydrophilic and encapsulated, whereas those of infrequent biotypes and of Acinetobacter genospecies 3 were, with few exceptions, hydrophobic and not encapsulated.

Capsule production might confer a greater virulence to Acinetobacter baumannii biotypes 8 and 9, and explain their higher prevalence in the studied hospital.