Departamento de Análises Clínicas e Biomedicina, Universidade Estadual de Maringá, PR, Brasil.
Braz J Med Biol Res. 2012 Feb;45(2):153-7. doi: 10.1590/s0100-879x2012007500011. Epub 2012 Feb 2.
Leprosy is an infectious disease caused by Mycobacterium leprae. The polymerase chain reaction (PCR) has been applied to detect M. leprae in different clinical samples and urine seems to be attractive for this purpose. PCR was used to improve the sensitivity for diagnosing leprosy by amplifying a 151-bp PCR fragment of the M. leprae pra gene (PCR-Pra) in urine samples. Seventy-three leprosy patients (39 males and 34 females, 14 to 78 years old) were selected for leprosy diagnosis at a reference laboratory in Maringá, PR, Brazil. Of these, 36 were under anti-leprosy multidrug therapy with dapsone and rifampicin for tuberculoid (TT) and dapsone, rifampicin and clofazimine for borderline (BB) and lepromatous (LL) forms. The control group contained 50 healthy individuals without any clinical history of leprosy. DNA isolated from leprosy patients' urine samples was successfully amplified by PCR-Pra in 46.6% (34/73) of the cases. The positivity of PCR-Pra for patients with the TT form was 75% for both patients under treatment and non-treated patients (P = 0.1306). In patients with the LL form, PCR-Pra positivity was 52 and 30% for patients under treatment and non-treated patients, respectively (P = 0.2386). PCR-Pra showed a statistically significant difference in detecting M. leprae between the TT and LL forms of leprosy in patients under treatment (P = 0.0033). Although the current study showed that the proposed PCR-Pra has some limitations in the detection of M. leprae, this method has the potential to be a useful tool for leprosy diagnosis mainly in TT leprosy where the AFB slit-skin smear is always negative.
麻风病是由麻风分枝杆菌引起的传染病。聚合酶链反应（PCR）已被应用于检测不同临床样本中的麻风分枝杆菌，而尿液似乎对此具有吸引力。PCR 被用于通过扩增麻风分枝杆菌 pra 基因的 151bp PCR 片段（PCR-Pra）来提高诊断麻风病的灵敏度，该片段存在于尿液样本中。73 例麻风病患者（39 名男性和 34 名女性，年龄 14 至 78 岁）在巴西马拉尼昂州马兰加的参考实验室被选来进行麻风病诊断。其中，36 例正在接受抗麻风多药治疗，包括氨苯砜和利福平用于结核样（TT），氨苯砜、利福平利和氯法齐明用于界限类（BB）和瘤型（LL）。对照组包含 50 名无任何麻风病临床病史的健康个体。从麻风病患者的尿液样本中成功提取出 DNA，PCR-Pra 在 46.6%（34/73）的病例中得到扩增。治疗和未治疗的 TT 形式患者的 PCR-Pra 阳性率均为 75%（P=0.1306）。在 LL 形式的患者中，治疗和未治疗的患者的 PCR-Pra 阳性率分别为 52%和 30%（P=0.2386）。在接受治疗的患者中，PCR-Pra 在 TT 和 LL 形式的麻风病之间检测麻风分枝杆菌的差异具有统计学意义（P=0.0033）。尽管本研究表明，所提出的 PCR-Pra 在检测麻风分枝杆菌方面存在一些局限性，但该方法有可能成为麻风病诊断的有用工具，主要是在 AFB 皮肤切片镜检总是阴性的 TT 麻风病中。
