Azimi P H, Chase P A
J Pediatr. 1981 Jun;98(6):995-1000. doi: 10.1016/s0022-3476(81)80616-6.
Forty patients with suspected non-CNS Hib infections were treated with cefamandole at a dosage of 100 to 150 mg/kg/day. Hib was isolated from 19 patients; three of the isolates were Blac+. All patients responded well without complications except for two children, both infected with Blac+ organisms, who subsequently developed meningitis, one three weeks following treatment for buccal cellulitis and bacteremia, the other while being treated with cefamandole for empyema. All strains of Hib were uniformly susceptible to cefamandole regardless of beta-lactamase production when tested with an inoculum of 10(4) cfu/ml. With 10(7) cfu/ml an inoculum effect was seen which was more pronounced with Blac+ strains. Moreover, "heavy" inoculum of Blac+ strains inactivated cefamandole in four to eight hours resulting in bacterial overgrowth. Similar results were obtained for ampicillin; chloramphenicol killed all strains regardless of inoculum size or beta-lactamase production. We conclude that cefamandole may be hydrolyzed by Blac+ organisms when present in large numbers, resulting in treatment failure. Extreme care should be taken in the choice of cefamandole for young infants with Hib infections, since this antibiotic neither cures nor prevents meningitis.
40例疑似非中枢神经系统b型流感嗜血杆菌（Hib）感染的患者接受了头孢孟多治疗，剂量为100至150mg/kg/天。从19例患者中分离出Hib；其中3株分离株产β-内酰胺酶（Blac+）。除了两名感染Blac+菌的儿童外，所有患者反应良好，无并发症发生。其中一名儿童在治疗颊部蜂窝织炎和菌血症三周后发生脑膜炎，另一名儿童在接受头孢孟多治疗脓胸时发生脑膜炎。当接种量为10⁴cfu/ml进行检测时，所有Hib菌株对头孢孟多均表现出一致的敏感性，无论其是否产β-内酰胺酶。当接种量为10⁷cfu/ml时，观察到接种量效应，且在Blac+菌株中更为明显。此外，大量的Blac+菌株接种物在4至8小时内使头孢孟多失活，导致细菌过度生长。氨苄西林也得到了类似的结果；氯霉素可杀死所有菌株，无论接种量大小或是否产β-内酰胺酶。我们得出结论，当大量存在时，Blac+菌可能会水解头孢孟多，导致治疗失败。对于患有Hib感染的幼儿，在选择头孢孟多时应格外谨慎，因为这种抗生素既不能治愈也不能预防脑膜炎。
