Bogale Tilahun, Mohammed Temesgen, Zewude Aboma, Khalifa Hazim O, Ameni Gobena
LeDeG Midwifery College Charity Organization, Addis Ababa, Ethiopia.
Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia.
Front Med (Lausanne). 2025 Sep 1;12:1641535. doi: 10.3389/fmed.2025.1641535. eCollection 2025.
Understanding the genetic makeup of complex (MTBC) strains is crucial, as lineage differences influence transmissibility, pathogenicity, and drug resistance patterns, all of which are essential for understanding MTBC transmission dynamics and designing effective TB control strategies. The present study investigated the genetic diversity of complex among pulmonary tuberculosis (TB) patients employed at Metahara Sugar Factory, located in Fentale district, East Showa Zone Oromia, central Ethiopia.
A cross-sectional study was conducted among 390 suspected pulmonary TB patients. Sputum samples were examined using Ziehl-Neelsen staining and cultured, followed by molecular characterizations of the isolates using region of difference 9 (RD9) deletion typing and spoligotyping.
Out of 390 participants, 96 (24.6%) were smear positive, and 89 (22.8%) were culture positive. RD9 deletion typing confirmed 88 isolates as . Further characterization of the 88 isolates using spoligotyping revealed 28 distinct spoligotyping patterns of which 15 unique (single isolates), and 13 shared among 73 clustered isolates. Among these, 19 matched shared international type (SITs) in the SpolDB4 database, while, 9 were novel (orphan) patterns. The predominant SITs were SIT523 (19.32%), SIT53 (13.6%), SIT149 (9.1%) and SIT289 (7.95%). Lineage analysis using TB-insight RUN TB-Lineage classified the strains primarily as Euro-American (63.64%), followed by Indo-Oceanic (20.45%), East-African-Indian (14.77%) and (1.14%).
The high clustering rate observed may suggest recent transmission; however, this must be interpreted cautiously due to the limited discriminatory power of spoligotyping, which may overestimate clustering and underestimate diversity. This underscores the need for targeted TB control strategies informed by enhanced molecular surveillance.
了解复杂的结核分枝杆菌复合群（MTBC）菌株的基因组成至关重要，因为谱系差异会影响传播性、致病性和耐药模式，所有这些对于理解MTBC传播动态和设计有效的结核病控制策略都至关重要。本研究调查了位于埃塞俄比亚中部奥罗米亚州东绍阿区芬塔莱区的梅塔哈拉糖厂工作的肺结核（TB）患者中MTBC复合群的遗传多样性。
对390例疑似肺结核患者进行了横断面研究。使用萋-尼染色法对痰标本进行检查并培养，随后使用差异区域9（RD9）缺失分型和间隔寡核苷酸分型（spoligotyping）对分离株进行分子特征分析。
在390名参与者中，96例（24.6%）涂片阳性，89例（22.8%）培养阳性。RD9缺失分型确认88株分离株为MTBC。使用间隔寡核苷酸分型对这88株分离株进行进一步特征分析，发现了28种不同的间隔寡核苷酸分型模式，其中15种是独特的（单个分离株），13种在73株聚集分离株中共有。其中，19种与SpolDB4数据库中的共享国际型（SITs）匹配，而9种是新的（孤儿）模式。主要的SITs是SIT523（19.32%）、SIT53（13.6%）、SIT149（9.1%）和SIT289（7.95%）。使用TB-insight RUN TB-Lineage进行的谱系分析将菌株主要分类为欧美型（63.64%），其次是印度洋型（20.45%）、东非-印度型（14.77%）和非洲型（1.14%）。
观察到的高聚集率可能表明近期传播；然而，由于间隔寡核苷酸分型的鉴别能力有限，可能会高估聚集率并低估多样性，因此对此必须谨慎解释。这突出了通过加强分子监测制定针对性结核病控制策略的必要性。
