诺卡菌病是一类由诺卡菌属感染人体引起的机会性感染性疾病，患者的临床表现多样，常累及肺部、皮肤软组织，也可出现播散性感染，累及中枢神经系统等部位，具有较高的病死率（平均26%）。随着免疫抑制人群数量扩大，诺卡菌病的发病率逐年升高。由于诺卡菌生长缓慢、形态学特征缺乏特异性，传统的培养和显微镜检查在其感染的临床诊断中存在检出率低、确诊时间长等局限，易导致误诊或延迟诊断。此外，诺卡菌属的不同菌种在好发地域、好发致病部位及耐药谱等特征方面均存在差异。近年来，随着分子生物学和高通量检测技术的发展，诺卡菌病的诊断技术取得了显著进展。针对16S rRNA及多基因序列的测定分析技术提高了菌种鉴定的准确率，也发现了多种与药敏试验耐药表型相关的耐药基因；宏基因组测序技术有助于提高检测阳性率、提升诊断速度，同时能够有效诊断混合感染的多种病原体；基质辅助激光解吸电离飞行时间质谱技术在数据库日益完善的条件下可实现比分子检测技术更快速、更经济的常规鉴定。将传统诊断方法与分子技术、质谱快速鉴定技术联合、互补，结合患者病情的紧急危重程度、所在医疗机构的检测条件等综合选择合适的诊断手段，可能可以进一步提高诺卡菌病诊断的准确率和时效性，最终改善患者的预后。

Nocardiosis is an opportunistic infectious disease caused by Nocardia species in humans, with diverse clinical manifestations. It commonly affects the lungs and skin/soft tissues, but can also present as disseminated infection involving the central nervous system and other sites. The disease has a high mortality rate (26% on average). As the population of immunosuppressed individuals continues to grow, the incidence of nocardiosis has been increasing year by year. Due to the slow growth of Nocardia and the lack of specific morphological features, traditional culture and microscopic examination have limitations in clinical diagnosis, such as low detection rates and long turnaround times, which may lead to misdiagnosis or delayed diagnosis. In addition, Nocardia species differ in geographic distribution, common sites of infection, and antimicrobial resistance profiles. In recent years, significant progress has been made in the diagnosis of nocardiosis, driven by advances in molecular biology and high-throughput detection technologies. Techniques targeting 16S rRNA and multilocus sequence analysis have improved the accuracy of species identification and have also revealed various resistance genes associated with resistance phenotypes in antimicrobial susceptibility testing. Metagenomic next-generation sequencing (mNGS) helps improve detection positivity rates and diagnostic speed, while also enabling the effective identification of multiple pathogens in polymicrobial infections. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), with increasingly comprehensive databases, can achieve faster and more cost-effective routine identification compared to molecular detection techniques. Combining traditional diagnostic methods with molecular techniques and rapid mass spectrometric identification in a complementary manner, and selecting appropriate diagnostic methods based on the urgency and severity of the patient's condition and the testing capabilities of the medical institutions may further improve the accuracy and timeliness of nocardiosis diagnosis, ultimately leading to improved patient outcomes.