Department of Medicine, Faculty of Health Sciences, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa.
S Afr Med J. 2020 Apr 29;110(5):422-426. doi: 10.7196/SAMJ.2020.v110i5.14035.
Tuberculosis (TB) is currently the leading cause of death from a single infectious agent worldwide. Patients who receive dialysis are particularly vulnerable to TB infection owing to immune dysfunction. Nonetheless, there is a paucity of incidence data on dialysis patients infected with TB in high-burden countries, such as South Africa (SA).
To determine the incidence of TB in prevalent chronic kidney disease stage 5 (CKD-5D) patients on dialysis at a single centre in Eastern Cape Province, SA, and to identify the risk factors associated with TB infection.
We conducted a retrospective cohort study of all consenting CKD-5D patients between April 2010 and March 2014 at Livingstone Hospital Renal Unit, Port Elizabeth, the Eastern Cape. TB was defined as definite or probable according to World Health Organization (WHO) criteria, and the cohort was split into those who developed TB (TB+) and those who did not (TB-).
One hundred and eleven patients were enrolled - predominantly black Africans (73%) and women (53%); the mean age (standard deviation (SD)) was 42 (9.8) years. The prevalence of HIV infection was 11%, all patients were receiving antiretroviral treatment and all had suppressed viral loads. Sixty-eight patients were on haemodialysis and 43 on peritoneal dialysis. Nineteen patients were diagnosed with 20 episodes of TB; 14 cases were pulmonary TB and 6 cases extrapulmonary TB. Of the patients with TB, 2 were HIV-infected, 7 (35%) were definite TB cases and 13 (65%) were probable cases. The calculated incidence rate was 4 505/100 000 patient years. Only informal housing (30% in TB+ v. 12% in TB-; p=0.042) and a history of hospitalisation (90% v. 76%, respectively; p=0.042) were significantly associated with a diagnosis of TB.
Dialysis patients in the Eastern Cape region of SA are at extremely high risk of acquiring TB, with an incidence rate 4.1 times that of the local population and >5 times that of the general SA population. Only informal housing and a history of hospitalisation were identified as positive risk factors for TB in this young population with a low HIV prevalence. Isoniazid prophylaxis in this high-risk group might be of benefit, but further studies are required to inform such treatment.
结核病（TB）是目前全球范围内单一感染源导致死亡的首要原因。由于免疫功能障碍，接受透析的患者尤其容易感染结核分枝杆菌。然而，在南非（SA）等高负担国家，针对透析患者感染结核分枝杆菌的发病率数据仍然较少。
在 SA 东开普省伊丽莎白港利文斯顿医院肾脏科的一个单一中心，确定普遍存在的慢性肾脏病 5 期（CKD-5D）透析患者中结核病的发病率，并确定与结核病感染相关的危险因素。
我们对 2010 年 4 月至 2014 年 3 月期间在伊丽莎白港利文斯顿医院肾脏科接受治疗的所有同意的 CKD-5D 患者进行了回顾性队列研究。根据世界卫生组织（WHO）的标准，结核病被定义为明确或可能，队列分为发生结核病（TB+）和未发生结核病（TB-）的患者。
共纳入 111 例患者，主要为黑非洲人（73%）和女性（53%），平均年龄（标准差）为 42（9.8）岁。HIV 感染率为 11%，所有患者均接受抗逆转录病毒治疗，且病毒载量均受到抑制。68 例患者接受血液透析，43 例患者接受腹膜透析。19 例患者被诊断为 20 例结核病发作，14 例为肺结核，6 例为肺外结核病。在结核病患者中，2 例为 HIV 感染者，7 例（35%）为明确结核病病例，13 例（65%）为可能病例。计算的发病率为 4505/100000 患者年。只有非正规住房（TB+患者中为 30%，TB-患者中为 12%；p=0.042）和住院史（TB+患者中为 90%，TB-患者中为 76%；p=0.042）与结核病的诊断显著相关。
SA 东开普省的透析患者感染结核分枝杆菌的风险极高，发病率是当地人群的 4.1 倍，是 SA 一般人群的 5 倍以上。在 HIV 流行率较低的年轻人群中，只有非正规住房和住院史被确定为结核病的阳性危险因素。在这一高危人群中，异烟肼预防可能有益，但需要进一步研究来确定这种治疗方法。
