Braun P, Tillotson J R, Wilcox C, Finland M
Appl Microbiol. 1968 Nov;16(11):1684-94. doi: 10.1128/am.16.11.1684-1694.1968.
A large number of recently isolated bacterial pathogens were tested for susceptibility to cephalexin and cephaloglycin by the replica inoculating method. Strains of group A hemolytic streptococci, viridans (alpha and gamma) streptococci, pneumococci, gonococci, meningococci, and penicillin G-sensitive Staphylococcus aureus were all moderately to highly susceptible to both of these cephalosporin analogues, nearly all of the strains being two to eight (median four) times more susceptible to cephaloglycin than to cephalexin. The penicillin G-resistant, penicillinase-producing strains of S. aureus varied in their susceptibility; many were moderately resistant to both analogues, particularly to cephalexin. Strains of enterococci, Haemophilus influenzae, and most of the common gram-negative bacilli were moderately to highly resistant. Reducing the size of the inoculum had variable effects on inhibition by these drugs, depending on the species or strain. The activity of cephalexin was very little affected by pH of the medium within the clinical range or by incubation at 37 C in broth for up to 24 hr. In contrast, cephaloglycin in broth deteriorated rapidly at 37 C, and its activity was markedly reduced in alkaline medium. Both cephalexin and cephaloglycin were rapidly absorbed and excreted into the urine after single oral doses of 500 mg. Much higher levels were achieved and sustained with the former. Absorption of both analogues was delayed when taken with food, and the levels in the serum were significantly higher and better sustained when probenecid was also given. Very high concentrations of cephalexin were excreted into the urine during the first 4 hr, and the levels were still high in the 4- to 8-hr collection. The concentrations of cephaloglycin in the urine at these times were much lower. An average of 80 to 93% of the dose of cephalexin and 25 to 30% of the cephaloglycin were accounted for as active drug in the urine collected in 8 hr. Both analogues were well tolerated.
采用影印接种法对大量近期分离出的细菌病原体进行了头孢氨苄和头孢甘氨酸敏感性测试。A组溶血性链球菌、草绿色（α和γ）链球菌、肺炎球菌、淋球菌、脑膜炎球菌以及对青霉素G敏感的金黄色葡萄球菌菌株对这两种头孢菌素类似物均表现出中度至高度敏感性，几乎所有菌株对头孢甘氨酸的敏感性比对头孢氨苄高两至八倍（中位数为四倍）。耐青霉素G、产青霉素酶的金黄色葡萄球菌菌株的敏感性各不相同；许多菌株对这两种类似物均表现出中度耐药，尤其对头孢氨苄。肠球菌、流感嗜血杆菌以及大多数常见革兰氏阴性杆菌菌株表现出中度至高度耐药。接种物大小的减小对这些药物的抑制作用有不同影响，这取决于菌种或菌株。在临床范围内，培养基的pH值或在肉汤中37℃孵育长达24小时对头孢氨苄的活性影响很小。相比之下，肉汤中的头孢甘氨酸在37℃时迅速降解，其活性在碱性培养基中显著降低。单次口服500毫克后，头孢氨苄和头孢甘氨酸均迅速被吸收并排泄到尿液中。前者达到并维持的水平要高得多。与食物一起服用时，两种类似物的吸收均延迟，同时给予丙磺舒时，血清中的水平显著更高且维持得更好。头孢氨苄在最初4小时内大量排泄到尿液中，在4至8小时收集的尿液中水平仍然很高。此时尿液中头孢甘氨酸的浓度要低得多。在8小时收集的尿液中，平均80%至93%的头孢氨苄剂量和25%至30%的头孢甘氨酸剂量被视为活性药物。两种类似物的耐受性都很好。
