[Incidence of colonization and infection by Acinetobacter baumannii in an endemic seting (ICU). Analysis of risk factors by means of a surveillance study].
BACKGROUND
Our ICU has witnessed a gradual increase in infections due to Acinetobacter baumannii complex that has reached a level of stable endemia since 1995. This situation, aggravated by a high degree of resistance, has led to the present prospective study, designed to establish the incidence of Acinetobacter colonization and to investigate the role of risk factors and their relation to environmental colonization.


METHODS
Serial sampling of all patients from the time of ICU admission to discharge. Sample collection from the environment and from hospital personnel. Monitorization of pre-established risk factors and detection of episodes of infection.


RESULTS
One-third of patients were colonized during their stay, with the trachea (43%), rectum (31%), and skin (35%) being the most frequent sites. In 92% of cases, colonization was established within the first 9 days after admission. Significant risk factors included mechanical ventilation (p < 0.01) and previous use of antibiotics (p < 0.007). Acinetobacter was recovered from thermometers (35%), respirator switches (43%), and damp surfaces (54%). Infection developed in 8% of patients; all had been previously colonized.


CONCLUSIONS
In an endemic setting, Acinetobacter colonization can occur in a third of ICU patients. This event is relatively early and often precedes infection. Duration of mechanical ventilation and previous use of antibiotics are the main risk factors. Environmental elements are frequent bacterial reservoirs, but the main reservoir is the colonized patient.
Martínez-Pellús
Antonio
A
Servicios de UCI y Microbiología. Hospital Universitario Virgen de la Arrixaca. Murcia. Spain.
Ruiz Gómez
Joaquín
J
Jaime Sánchez
Francisco
F
Simarro Córdoba
Encarna
E
Fernández Lozano
Juan Antonio
JA
D000150:Acinetobacter / Q000187:drug effects / Q000302:isolation & purification*; D000151:Acinetobacter Infections / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission; D000328:Adult; D000368:Aged; D002353:Carrier State / Q000453:epidemiology; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission; D004197:Disease Reservoirs; D024881:Drug Resistance, Bacterial; D004866:Equipment Contamination; D004865:Equipment and Supplies, Hospital; D005260:Female; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D011446:Prospective Studies; D012007:Rectum / Q000382:microbiology; D012307:Risk Factors; D012867:Skin / Q000382:microbiology; D013030:Spain / Q000453:epidemiology; D015163:Superinfection / Q000453:epidemiology / Q000382:microbiology; D014132:Trachea / Q000382:microbiology