Chawla Rohan, Singh Mithalesh K, Singh Lata, Shah Pooja, Kashyap Seema, Azad Shorya, Venkatesh Pradeep, Sen Seema
Associate Professor, Department of Ophthalmology, Dr. R. P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, 110029 India.
Department of Ocular Pathology, Dr. R. P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
Ther Adv Ophthalmol. 2022 Sep 18;14:25158414221123522. doi: 10.1177/25158414221123522. eCollection 2022 Jan-Dec.
The definitive diagnosing of ocular tuberculosis (TB) is difficult; therefore, there is a need of better understanding of investigating TB DNA in presumed ocular TB patients.
The aim of this study is to correlate tubercular DNA PCR of aqueous/vitreous and blood in cases of presumed ocular TB.
A prospective study.
DNA was extracted from aqueous of cases of choroidal tuberculoma (group 1) and serpiginous choroiditis (group 2) and from vitreous of cases of vasculitis (group 3) and macular hole/retinal detachment (group 4). Gel-based PCR and real-time PCR amplification were performed using IS6110 primer on ocular fluids. The same was also performed on the blood samples of cases in which tubercular DNA was detected in the ocular fluids.
Overall, 31 cases were analysed in our study. Tubercular DNA was detected in ocular fluids of seven cases: group 1, two cases (67%); group 2, one case (17%); group 3, four cases (27%); and no case of group 4. Blood samples of six of these seven patients were positive for tubercular DNA. Of these six patients, four had evidence of systemic TB and were on ATT. Two cases had no evidence of active systemic TB, yet PCR was positive from blood and ocular fluids.
Tubercular DNA detected from ocular fluids may possibly be due to bystander DNA and may not indicate primary ocular tubercular infection. Thus, caution must be exercised prior to labelling a case of uveitis as being tubercular based on the results of molecular assays on ocular fluids alone. The results of PCR on ocular fluids should be correlated with PCR on blood and systemic findings.
眼部结核病的明确诊断较为困难；因此，有必要更好地了解在疑似眼部结核病患者中检测结核 DNA 的情况。
本研究的目的是关联疑似眼部结核病病例中房水/玻璃体和血液的结核 DNA PCR 结果。
一项前瞻性研究。
从脉络膜结核瘤病例（第 1 组）和匐行性脉络膜炎病例（第 2 组）的房水中以及血管炎病例（第 3 组）和黄斑裂孔/视网膜脱离病例（第 4 组）的玻璃体中提取 DNA。使用 IS6110 引物对眼内液进行基于凝胶的 PCR 和实时 PCR 扩增。在眼内液中检测到结核 DNA 的病例的血液样本也进行了同样的检测。
总体而言，我们的研究分析了 31 例病例。7 例病例的眼内液中检测到结核 DNA：第 1 组，2 例（67%）；第 2 组，1 例（17%）；第 3 组，4 例（27%）；第 4 组未检测到。这 7 名患者中有 6 名的血液样本结核 DNA 呈阳性。在这 6 名患者中，4 名有系统性结核病的证据且正在接受抗结核治疗。2 例没有活动性系统性结核病的证据，但血液和眼内液的 PCR 呈阳性。
从眼内液中检测到的结核 DNA 可能是由于旁观者 DNA，可能并不表明原发性眼部结核感染。因此，仅根据眼内液分子检测结果将葡萄膜炎病例标记为结核性时必须谨慎。眼内液 PCR 的结果应与血液 PCR 和全身检查结果相关联。
