Lorian V, Waluschka A, Kim Y
J Clin Microbiol. 1982 Aug;16(2):382-6. doi: 10.1128/jcm.16.2.382-386.1982.
Filaments of Klebsiella pneumoniae were observed by Gram stain in the sputum of a patient with a respiratory infection who was treated with half the usual dose of cefazolin. Identical filaments were observed in vitro when this strain was incubated with subminimum inhibitory concentrations of cefazolin. Large gram-positive cocci containing multiple cross walls were observed by electron microscopy in the sputum of a patient with a respiratory infection who was treated with ampicillin and gentamicin. Antibiotic administration was suspended the night before the sputum was obtained. The ultrastructure of these cocci was very similar to the ultrastructure of Staphylococcus aureus incubated with subminimum inhibitory concentrations of cephaloridine or oxacillin. It was suspected that the low dose of cefazolin and the intermittent therapy with ampicillin resulted in a subminimum inhibitory concentration of antibiotic in the respiratory tract which induced the the abnormal morphology of the bacteria observed in the sputum of both patients. The presence of abnormal forms of bacteria in the specimen of a patient, rather than in the culture of a specimen, has clinical significance.
在一名接受常规剂量一半的头孢唑林治疗的呼吸道感染患者的痰液中，通过革兰氏染色观察到肺炎克雷伯菌的丝状体。当该菌株与低于最低抑菌浓度的头孢唑林一起孵育时，在体外观察到了相同的丝状体。在一名接受氨苄西林和庆大霉素治疗的呼吸道感染患者的痰液中，通过电子显微镜观察到含有多个横壁的大革兰氏阳性球菌。在获取痰液的前一天晚上停止了抗生素给药。这些球菌的超微结构与用低于最低抑菌浓度的头孢菌素或苯唑西林孵育的金黄色葡萄球菌的超微结构非常相似。怀疑低剂量的头孢唑林和氨苄西林的间歇治疗导致呼吸道中抗生素处于低于最低抑菌浓度，从而导致在两名患者痰液中观察到细菌的异常形态。患者标本中而非标本培养物中存在异常形态的细菌具有临床意义。
