Data_Sheet_1_Case Report: Metagenomic Next-Generation Sequencing in Diagnosis of Disseminated Tuberculosis of an Immunocompetent Patient.docx

Disseminated tuberculosis (TB) is a rare disease and mainly occurs in immunodeficient patients. It is marked by hematogenous or lymphatic dissemination of Mycobacterium tuberculosis, causing tuberculous infection involving any organ system. Here, we report a case of disseminated TB involving lung, liver, spine, mediastinum, and prostate in an immunocompetent man. The present patient found a hepatic mass without any symptom during health examination. In the next 2 years, further examinations revealed multiple lesions in the lung, mediastinum, spine, and prostate. Imaging examinations, such as contrast-enhanced abdominal CT, F-18 FDG-PET/CT, and radionuclide bone scan, suggested the diagnosis of malignancy or metastatic tumor. Furthermore, histopathological results of the biopsies of the hepatic mass, mediastinal mass, and prostatic mass demonstrated granulomatous inflammation. Therefore, metagenomic next-generation sequencing (mNGS) was utilized to confirm the diagnosis. Mycobacterium tuberculosis complex was simultaneously detected in the spinal surgical resection specimens and bronchoalveolar lavage fluid (BALF), indicating the diagnosis of disseminated TB. mNGS is an emerging molecular diagnostic technology, and its application in disseminated TB has been rarely reported. We highlight that disseminated TB should be considered even in an immunocompetent patient, and mNGS can be performed when the diagnosis is difficult.

播散型结核病（disseminated tuberculosis, TB）是一种罕见疾病，主要发生于免疫功能低下患者，其病理特征为结核分枝杆菌经血行或淋巴道播散，导致累及任一器官系统的结核分枝杆菌感染。本文报道1例免疫功能正常男性患者罹患累及肺、肝、脊柱、纵隔及前列腺的播散型结核病。本例患者在健康体检时发现肝脏占位，无任何临床症状。后续2年间，进一步检查发现肺、纵隔、脊柱及前列腺存在多发病灶。影像学检查包括腹部增强CT、氟-18氟代脱氧葡萄糖正电子发射断层显像/计算机断层扫描（F-18 FDG-PET/CT）、放射性核素骨扫描，均提示为恶性肿瘤或转移性肿瘤。此外，肝脏占位、纵隔占位及前列腺占位的活检组织病理结果均提示肉芽肿性炎。因此，遂采用宏基因组二代测序（metagenomic next-generation sequencing，mNGS）以明确诊断。脊柱手术切除标本及支气管肺泡灌洗液（bronchoalveolar lavage fluid，BALF）中同时检出结核分枝杆菌复合群，据此确诊播散型结核病。宏基因组二代测序是一种新兴的分子诊断技术，其在播散型结核病中的应用报道较为少见。本文强调，即便患者免疫功能正常，也应考虑播散型结核病的可能；当诊断困难时，可采用宏基因组二代测序辅助检测。