IntroductionAlthough early use of broad-spectrum antimicrobials in critically ill patients may increase antimicrobial adequacy, uncontrolled use of these agents may select for more-resistant organisms. This study investigated the effects of early use of broad-spectrum antimicrobials in critically ill patients with hospital-acquired pneumonia.MethodsWe compared the early use of broad-spectrum antimicrobials plus subsequent de-escalation (DE) with conventional antimicrobial treatment (non-de-escalation, NDE) in critically ill patients with hospital-acquired pneumonia (HAP). This open-label, randomized clinical trial was performed in patients in a tertiary-care center medical intensive care unit (MICU) in Korea. Patients (n = 54) randomized to the DE group received initial imipenem/cilastatin plus vancomycin with subsequent de-escalation according to culture results, whereas patients randomized to the NDE group (n = 55) received noncarbapenem, nonvancomycin empiric antimicrobials.ResultsBetween November 2004 and October 2006, 109 MICU patients with HAP were enrolled. Initial antimicrobial adequacy was significantly higher in the DE than in the NDE group for Gram-positive organisms (100% versus 14.3%; P < 0.001), but not for Gram-negative organisms (64.3% versus 85.7%; P = 0.190). Mean intensive care unit (ICU) stay, and 14-day, 28-day, and overall mortality rates did not differ in the two groups. Among culture-positive patients, mortality from methicillin-resistant Staphylococcus aureus (MRSA) pneumonia was higher in the DE group, even after early administration of vancomycin. Multidrug-resistant organisms, especially MRSA, were more likely to emerge in the DE group (adjusted hazard ratio for emergence of MRSA, 3.84; 95% confidence interval, 1.06 to 13.91).ConclusionsThe therapeutic advantage of early administration of broad-spectrum antimicrobials, especially with vancomycin, was not evident in this study.

Objective. To assess the incremental costeffectiveness of 3 Pneumocystis carinii pneumonia (PCP) prophylaxis strategies in patients with Wegener's granulomatosis (WG) receiving immunosuppressive therapies: 1) no prophylaxis; 2) trimethoprim/sulfamethoxazole (TMP/SMX) 160 mg/800 mg 3 times a week, which is discontinued if patients experience an adverse drug reaction (ADR); and 3) TMP/SMX 160 mg/800 mg 3 times a week, which is replaced by monthly aerosolized pentamidine (300 mg) if patients experience an ADR.Methods. A Markov state-transition model was developed to follow a hypothetical cohort of WG patients over their lifetimes starting from the time of initial exposure to the immunosuppressive therapy. The effect of PCP prophylaxis on life expectancy, quality-adjusted life expectancy, average discounted lifetime cost (ADLC), and incremental cost-effectiveness was estimated based on data obtained from a literature review. Direct medical costs were examined from a societal perspective, and costs and benefits were discounted at 3% annually.Results. No prophylaxis resulted in a life expectancy of 13.36 quality-adjusted life years (QALY) at an ADLC of $4,538. In comparison, prophylaxis with TMP/ SMX alone increased the QALY to 13.54 and was cost saving, with an ADLC of $3,304. The addition of pentamidine in patients who had an ADR to TMP/SMX resulted in 13.61 QALY, with an ADLC of $7,428. Compared with TMP/SMX alone, TMP/SMX followed by pentamidine increased the QALY by 0.07 at an incremental cost of $58,037 per QALY. Both TMP/SMX alone and TMP/SMX followed by pentamidine prophylaxis strategies dominated the no prophylaxis strategy until the incidence of PCP fell below 0.2% and 2.25%, respectively. Institution of pentamidine therapy for patients with a TMP/SMX ADR increased qualityadjusted life expectancy compared with that with TMP/ SMX alone until the incidence of PCP rose above 7.5%.Conclusion. Prophylaxis using TMP/SMX alone increased life expectancy and reduced cost for patients with WG receiving immunosuppressive therapy. Replacing TMP/SMX with monthly aerosolized pentamidine in cases of ADR further increased life expectancy, although at an increased cost.