ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, Utah, USA.
Antimicrob Agents Chemother. 2014;58(2):795-800. doi: 10.1128/AAC.01531-13. Epub 2013 Nov 18.
The genus Nocardia has undergone rapid taxonomic expansion in recent years, and an increasing number of species are recognized as human pathogens. Many established species have predictable antimicrobial susceptibility profiles, but sufficient information is often not available for recently described organisms. Additionally, the effectiveness of sulfonamides as first-line drugs for Nocardia has recently been questioned. This led us to review antimicrobial susceptibility patterns for a large number of molecularly identified clinical isolates. Susceptibility results were available for 1,299 isolates representing 39 different species or complexes, including 11 that were newly described, during a 6-year study period. All tested isolates were susceptible to linezolid. Resistance to trimethoprim-sulfamethoxazole (TMP-SMX) was rare (2%) except among Nocardia pseudobrasiliensis (31%) strains and strains of the N. transvalensis complex (19%). Imipenem susceptibility varied for N. cyriacigeorgica and N. farcinica, as did ceftriaxone susceptibility of the N. nova complex. Resistance to more than one of the most commonly used drugs (amikacin, ceftriaxone, TMP-SMX, and imipenem) was highest for N. pseudobrasiliensis (100%), N. transvalensis complex (83%), N. farcinica (68%), N. puris (57%), N. brasiliensis (51%), N. aobensis (50%), and N. amikacinitolerans (43%). Thus, while antimicrobial resistance can often be predicted, susceptibility testing should still be considered when combination therapy is warranted, for less well characterized species or those with variable susceptibility profiles, and for patients with TMP-SMX intolerance.
近年来，诺卡氏菌属的分类学迅速扩展，越来越多的物种被认为是人类病原体。许多已确立的物种具有可预测的抗菌药物敏感性谱，但对于最近描述的生物体，通常没有足够的信息。此外，磺胺类药物作为诺卡氏菌的一线药物的有效性最近受到了质疑。这促使我们回顾了大量分子鉴定的临床分离株的抗菌药物敏感性模式。在 6 年的研究期间，有 1,299 个分离株代表 39 种不同的种或复合种，包括 11 种新描述的种，可获得药敏结果。所有测试的分离株均对利奈唑胺敏感。除了 Nocardia pseudobrasiliensis（31%）菌株和 Nocardia transvalensis 复合种（19%）菌株外，对 trimethoprim-sulfamethoxazole（TMP-SMX）的耐药性罕见（2%）。Nocardia cyriacigeorgica 和 Nocardia farcinica 对亚胺培南的敏感性不同，Nocardia nova 复合种对头孢曲松的敏感性也不同。对阿米卡星、头孢曲松、TMP-SMX 和亚胺培南等最常用药物中的一种以上耐药的比率最高的是 Nocardia pseudobrasiliensis（100%）、Nocardia transvalensis 复合种（83%）、Nocardia farcinica（68%）、Nocardia puris（57%）、Nocardia brasiliensis（51%）、Nocardia aobensis（50%）和 Nocardia amikacinitolerans（43%）。因此，虽然通常可以预测抗菌药物耐药性，但在需要联合治疗、对特征描述较差的物种或具有可变药敏谱的物种以及对 TMP-SMX 不耐受的患者时，仍应考虑进行药敏试验。
