Jetlund O, Thurmann-Nielsen E, Walstad R A
Department of Otolaryngology, University Clinic, Trondheim, Norway.
Int J Clin Pharmacol Res. 1991;11(1):1-6.
In the study described, the pharmacokinetics of two oral betalactams, cefuroxime axetil and phenoxymethylpenicillin, were compared with respect to their penetration into tonsil tissue. Seventeen patients were given cefuroxime axetil 500 mg single dose and 16 patients were given phenoxymethylpenicillin 650 mg single dose, at different time intervals before tonsillectomy. The tonsils were freeze-dried and the drug concentrations in serum and tissue determined by a high performance liquid chromatographic method. Cefuroxime axetil showed a slightly better penetration ratio (mean 35%, median 32%) than phenoxymethylpenicillin (mean 31%, median 24%) however the difference was not statistically significant. The bioavailability of cefuroxime axetil was low due to being administered in the fasting state. The relatively low penetration ratios of both drugs into samples of whole tissue can be explained by the localization of betalactam antibiotics primarily in the extracellular fluid, with low penetration into normal cells. Both drugs were found to reach concentrations in tonsil tissue above the minimum inhibitory concentration for Group A beta-haemolytic streptococci after a single oral dose. In addition to streptococci, Haemophilus influenzae and beta-lactamase producing Staphylococcus aureus were isolated in a significant number of the tonsils. These bacteria may play a pathogenic role, but this was not investigated.
在所描述的研究中，比较了两种口服β-内酰胺类药物头孢呋辛酯和青霉素V钾的药代动力学及其在扁桃体组织中的渗透情况。17例患者在扁桃体切除术前不同时间间隔单剂量给予500mg头孢呋辛酯，16例患者单剂量给予650mg青霉素V钾。将扁桃体冻干，采用高效液相色谱法测定血清和组织中的药物浓度。头孢呋辛酯的渗透比（平均35%，中位数32%）略高于青霉素V钾（平均31%，中位数24%），但差异无统计学意义。由于在空腹状态下给药，头孢呋辛酯的生物利用度较低。两种药物在全组织样本中的相对低渗透比可以用β-内酰胺类抗生素主要定位于细胞外液且对正常细胞的渗透率低来解释。单次口服给药后，两种药物在扁桃体组织中的浓度均达到高于A组β溶血性链球菌最低抑菌浓度的水平。除链球菌外，在大量扁桃体中还分离出流感嗜血杆菌和产β-内酰胺酶的金黄色葡萄球菌。这些细菌可能起致病作用，但未对此进行研究。
