Treatment for MRSA with glycopeptides (鄭正威醫師)

Teicoplanin 是屬於複合物，由主結構以及R-side chain 的fatty acid組成。裏頭各複合物的組成比例主要受到製成過程的影響，因此製成過程若是不專一，產出的複合物比例就會不均。

複合物組成比例不一會造成體內BE的改變而影響組織濃度分布。在歐盟曾有Teicoplanin generic送審結果發現因複合物比例不一，Generic teicoplanin在體內內代謝的速度較快，無法維持有效血中濃度。基於以上理由，EMA並無核准Generic Teicoplanin在歐盟上市。

( 5-15 mg/L in 2004 Guideline)

A subgroup analysis of patients with MSSA pneumonia determined to be correctly treated with either vancomycin or cloxacillin showed significantly greater infection-related mortality in the vancomycin group as compared to the cloxacillin group (47% vs 0%, respectively, P<0.01)1

Reference: 1. González C, Rubio M, Romero-Vivas J, González M, Picazo JJ. Bacteremia pneumonia due to Staphylococcus aureus: a comparison of disease caused by methicillin-resistant and methicillin-susceptible organisms. Clin Infect Dis. 1999;29:1171-1177.

Lamer et al1 studied the penetration of vancomycin in the lung epithelial lining fluid (ELF) of 14 critically ill, ventilated patients who had received vancomycin for at least 5 days at an initial dose of 15 mg/kg.

Using fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) just prior to the next planned injection of vancomycin (at a time approximating the minimal concentration of vancomycin in plasma), the investigators determined1:

Mean vancomycin concentration in ELF was 4.5 ± 2.3 µg/mL (range = 0.4–8.1 µg/mL). The mean vancomycin concentration in plasma was 24 ± 10 µg/mL
However, 5/14 (36%) patients exhibited ELF concentrations less than 4 µg/mL, the breakpoint for susceptible S aureus
Vancomycin mean simultaneous plasma concentration was high (24 µg/mL)

Results were obtained for 14 patients.1

Reference: 1. Lamer C, De Beco V, Soler P, et al. Analysis of vancomycin entry into pulmonary lining fluid by bronchoalveolar lavage in critically ill patients. Antimicrob Agents Chemother. 1993;37:281-286.