[Intravenous colistin in the treatment of infections due to pan-resistant Gram negative bacilli].
Emergence of panresistant gram negative bacilli has lead to the progressive reintroduction of intravenous colistin.


OBJECTIVE
To describe the clinical experience observed with this compound.


METHODS
A retrospective analysis was performed for all treatments lasting >/= 48 hours. Medical records were analyzed to obtain clinical parameters and microbiological data, evaluate clinical response and evolution until discharge.


RESULTS
24 treatments lasting >/= 48 hours were applied between June 2005 and September 2006. Intravenous colistin was indicated to treat cases of ventilator-associated (VA) pneumonia (n = 10; 41.7%), abscess or collections (12.5%), bloodstream infections, non-VA pneumonia or urinary tract infections (4.2% each one, respectively). Treatment was initiated on average at 3.2 days (+/- 2.85) from diagnosis of infection. All courses were microbiologically-guided, and involved P. aeruginosa or A. baumannii isolates. Susceptibility was evaluated by E-test in 11 isolates (MIC90 3.6 nicrog/mL, range 0.38 to 4 microg/mL). One isolate was resistant to colistin (9%). A favorable response was observed in 12 treatments (50%) with a relapse in 5 cases (41.7%). Being treated for pneumonia was the only factor associated to failure, (p = 0.04) Eradication was documented in 8 cases (33.3%) and persistence in 11 (45.8%). In 5 cases a microbiological follow-up was not available. Survival at time of discharge was 45.5%. (n = 10) None of the treatment courses was associated with nefrotoxicity.


CONCLUSIONS
Intravenous colistin is a safe compound useful to treat various nosocomial infections due to pan-resistant gram negative bacilli. Nonetheless, its clinical efficacy is limited, especially among patients treated for nosocomial pneumonia.
Fica C
Alberto
A
Sección de Infectología, Hospital Clínico Universidad de Chile, Santiago, Chile. afica@redclinicauchile.cl
Céspedes J
Ignacio
I
Gompertz G
Macarena
M
Jalón V
Mauricio
M
Sakurada Z
Andrea
A
Sáez L
Enzo
E
D018806:APACHE; D000151:Acinetobacter Infections / Q000188:drug therapy* / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000187:drug effects*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D003091:Colistin / Q000008:administration & dosage / Q000627:therapeutic use*; D003428:Cross Infection / Q000188:drug therapy / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011552:Pseudomonas Infections / Q000188:drug therapy* / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D012189:Retrospective Studies; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D003091:Colistin