Garau J
Hospital de Mutua de Terrassa, Barcelona, Spain.
Intensive Care Med. 1994 Jul;20 Suppl 3:S5-9. doi: 10.1007/BF01745244.
Production of beta-lactamases is the most important means of bacterial resistance to beta-lactam antibiotics. The traditional, plasmid-mediated beta-lactamases were initially confined to Enterobacteriaceae but have now spread to other genera and species including Pseudomonas aeruginosa, Haemophilus influenzae, and Neisseria gonorrhoeae. Extended-spectrum plasmid-mediated beta-lactamases have been identified in Enterobacteriaceae, particularly Klebsiella spp. and Escherichia coli. They are capable of hydrolyzing second- and third-generation cephalosporins and older beta-lactams. Chromosomally mediated beta-lactamases may be produced constitutively or induced by the presence of a beta-lactam. Mutation within the bacterial genome may lead to constitutive enzyme hyperproduction. Strains that produce these enzymes are resistant to practically all beta-lactams, with the exception of carbapenems. The wide-spread occurrence of antibiotic resistance dictates that therapies be judiciously chosen with attention to the resistance patterns of the causative organisms.
产生β-内酰胺酶是细菌对β-内酰胺类抗生素耐药的最重要方式。传统的质粒介导的β-内酰胺酶最初局限于肠杆菌科细菌，但现在已传播到其他属和种，包括铜绿假单胞菌、流感嗜血杆菌和淋病奈瑟菌。在肠杆菌科细菌中已鉴定出超广谱质粒介导的β-内酰胺酶，尤其是克雷伯菌属和大肠埃希菌。它们能够水解第二代和第三代头孢菌素以及较老的β-内酰胺类药物。染色体介导的β-内酰胺酶可以组成性产生，也可由β-内酰胺的存在诱导产生。细菌基因组内的突变可能导致组成性酶的过量产生。产生这些酶的菌株实际上对所有β-内酰胺类药物耐药，但碳青霉烯类除外。抗生素耐药性的广泛出现表明，治疗方法应根据致病微生物的耐药模式谨慎选择。
