Nationwide multicenter survey on the pathophysiology of hospital-acquired pneumonia and the use of first-line antibiotics in Japan: Evaluation of clinical position of meropenem in the initial therapy of hospital-acquired pneumonia

Through a nationwide, collaborative, multicenter survey to investigate the pathophysiological profile of hospital-acquired pneumonia (HAP) and the use of first-line antibiotics, we evaluated the clinical position of meropenem (MEPM) in the initial therapy of HAP. A prospective survey was conducted of consecutively-enrolled patients with HAP in the period from June 2002 to May 2004. Data were collected for a total of 1,460 patients from 254 institutions across Japan. Among the cases analyzed for patient profiles (1,356 patients), 661 cases were treated with MEPM among the first-line antibiotic. Of the MEPM-treated cases, monotherapy accounted for 76.6%. Among cases treated with MEPM combination therapy, clindamycin was used in 24.5%, followed in descending order by tetracyclines and aminoglycosides. MEPM was preferably used for serious cases or cases having many risk factors defined in the Japanese Respiratory Society Guidelines for Management of HAP in Adults. As for the distribution of the disease type, moderate pneumonia with a risk factor or severe pneumonia [Group III: type C] and pneumonia with specific conditions [Group IV: type D∼ H] accounted for 91.7% of all cases. The response rate was 54.4% when MEPM was used as a first-line medication, and 47.2% when carbapenems were not used. Most of the MEPM-treated patients were the dosage which is normal in Japan (0.25-0.5 g × 2/day). As the main causative organisms of HAP were antibiotic-resistant bacteria such as Pseudomonas aeruginosa, future revisions of the HAP guideline should incorporate consideration of antibiotics dosage based on the PK/PD theory. As for safety, main adverse drug reactions in MEPM-treated patients were hepatic function disorder. Unlabelled serious adverse drug reactions were not reported. In conclusion, the results from this study suggest that MEPM plays an important role in the initial therapy of HAP.