Chew Yi Rong, Tay Jun Yang, Kyaw Win Mar, Chia Po Ying, Ng Deborah Hee Ling
National Centre for Infectious Diseases, Singapore; Department of Infectious Diseases, Tan Tock Seng Hospital, Singapore.
National Centre for Infectious Diseases, Singapore; Department of Infectious Diseases, Tan Tock Seng Hospital, Singapore.
Int J Infect Dis. 2025 Apr;153:107768. doi: 10.1016/j.ijid.2024.107768. Epub 2024 Dec 24.
Subclinical tuberculosis (TB) is challenging to diagnose due to the lack of a clear definition and symptoms. This study aimed to describe the subclinical disease spectrum among people with culture-confirmed pulmonary TB routinely diagnosed in Singapore, a country with moderate incidence, using different definitions. It also aimed to identify risk factors for subclinical TB and the current diagnostic approaches in detecting subclinical TB.
A retrospective analysis of sputum culture-positive pulmonary TB cases reported to the Singapore National TB Registry from January 1, 2004 to December 31, 2023 was conducted. Two definitions for subclinical TB were used: sputum culture-positive TB with no cough or cough for less than 2 weeks for definition 1 and no cough for definition 2.
Of 18,693 pulmonary TB cases notified, 41.6% and 31.6% met the first and second definition of subclinical TB, respectively. However, neither definition performed better in detecting subclinical TB (receiver operating characteristics curve). The majority of cases (96.7% and 96.0% respectively) had abnormal chest X-ray findings, and a high proportion had smear-positive results (40.0% and 35.6%, respectively). Sputum TB polymerase chain reaction (PCR) was significant in picking up subclinical TB adjusted odds ratio 1.20 (95% confidence interval 1.10-31), although 42.2% with no persistent cough and 41.2% with no cough did not have sputum TB PCR tested, highlighting gaps in diagnostic practices. Together, older adults (aged ≥70 years) and immunocompromised individuals, including those with end-stage renal failure, steroid therapy, malignancy, and HIV, were more likely to have subclinical TB.
Our study suggests that subclinical TB are more likely to occur in those older than 70 years and those with immunocompromising conditions. The use of diagnostics such as chest X-ray and sputum TB PCR are helpful in diagnosing subclinical TB. Further research is necessary to evaluate other screening tools in detecting these early disease states.
由于缺乏明确的定义和症状，亚临床结核病的诊断具有挑战性。本研究旨在描述在发病率中等的新加坡，使用不同定义对常规诊断为痰培养确诊肺结核患者中的亚临床疾病谱。研究还旨在确定亚临床结核病的危险因素以及当前检测亚临床结核病的诊断方法。
对2004年1月1日至2023年12月31日向新加坡国家结核病登记处报告的痰培养阳性肺结核病例进行回顾性分析。采用了两种亚临床结核病的定义：定义1为痰培养阳性且无咳嗽或咳嗽少于2周，定义2为无咳嗽。
在18693例报告的肺结核病例中，分别有41.6%和31.6%符合亚临床结核病的第一和第二个定义。然而，在检测亚临床结核病方面，两种定义的表现均不佳（受试者工作特征曲线）。大多数病例（分别为96.7%和96.0%）胸部X线检查结果异常，且涂片阳性率较高（分别为40.0%和35.
