[Treatment of severe respiratory infection. Legionella pneumonia]

This paper discusses the evaluation of new macrolides and new quinolones for the treatment of Legionnaires' disease in in vitro susceptibility test, penetration to polynuclear leukocytes and treatment in an animal model. Some kinds of biological response modifier (BRMs) such as granulocyte colony stimulating factor (GCSF), monocyte CSF (M-CSF), GM-CSF, recombinant interleukin-1 (IL-1) and IL-2 were also evaluated. The antimicrobial activity (MIC) of new macrolides to Legionella pneumophila (45 strains) showed the highest activity in TE-031 (Taisho Pharmaceutical Co., Tokyo, Japan) and then rokitamycin (RKM), RU-28965 (Roussel, France), erythromycin (EM), josamycin (JM) in decreasing order of activity. According to the results of the data of cell-penetration and survival rate after treatment of guinea pigs with experimental Legionella pneumonia, the new macrolides such as TE-031, RKM and RU-28965 are expected to be more effective in the treatment of Legionnaires' disease than EM. New quinolones such as ciprofloxatin (CPFX), NY-198 (Hokuriku Pharmaceutical Co., Japan) or T-3262 (Toyama Kagaku Pharmaceutical Co., Toyama Japan) were compared to ofloxacin (OFLX), enoxacin (ENX) or rifampin (RFP) for evaluation. These drugs showed excellent activity against L. pneumophila and good penetration to polynuclear leukocytes. Regarding the treatment of guinea pig with legionella pneumonia, OFLX was the most effective, and NY-198 or T-3262 were more effective than EM treatment. The highest survival rate was obtained with IL-2 in infected guinea pigs. We also observed the efficacy of combined use of IL-2 and HR-8 10 (Horchst FRG) which is a newly developed cephem antibiotic.(ABSTRACT TRUNCATED AT 250 WORDS)