Instituto de Patología Experimental, Facultad de Ciencias de la Salud, Universidad Nacional de Salta/Consejo Nacional de Investigaciones Científicas y Técnicas, Salta, Argentina.
BMC Infect Dis. 2012 Aug 15;12:191. doi: 10.1186/1471-2334-12-191.
The diagnosis of the leishmaniases poses enormous challenges in Argentina. The Polymorphism-Specific PCR (PS-PCR) designed and validated in our laboratories has been proven effective for typifying the Leishmania genus from cultured material. Here we evaluated the performance of this method in the diagnosis of American tegumentary leishmaniasis (ATL) and the rapid identification of Leishmania spp. directly from clinical specimens.
A total of 63 patients from northwestern Argentina, with cutaneous or mucocutaneous lesions, underwent an ATL diagnosis protocol which included clinical examination, Leishmanin skin test, and microscopic examination of dermal smears. In addition, we performed PS-PCR on DNA directly extracted from the specimens scraped from the lesions.
Out of the 63 patients, 44 were classified as ATL cases and 19 as non-ATL cases. The diagnostic sensitivity of the microscopic analysis of dermal smears and PS-PCR individually were 70.5% and 81%, respectively. When performing both tests in parallel, this parameter increased significantly to 97.6% (p = 0.0018). The specificities, on the other hand, were 100%, 84.2%, and 83.3% for the combination, respectively (p > 0.05). Using the PS-PCR analysis we successfully identified the Leishmania spp. in 31 out of the 44 ATL cases. Twenty-eight (90.3%) cases were caused by L. (V.) braziliensis, two (6.5%) by L. (V.) guyanensis, and one (3.2%) by L. (V.) panamensis.
The efficacy of the ATL diagnosis was significantly improved by combining the dermal smear examination with a PS-PCR analysis. Our strategy allowed us to reach the diagnosis of ATL with high accuracy regarding the species of the etiological agent in 70.5% of the cases. Moreover, we diagnosed two cases of the disseminated cutaneous form caused by L. (V.) braziliensis and a cutaneous case due to L. (V.) panamensis infection, both findings reported for the first time in Argentina.
在阿根廷，利什曼病的诊断极具挑战性。我们实验室设计和验证的多态性特异性 PCR（PS-PCR）已被证明可有效对培养物中的利什曼属进行分类。在此，我们评估了该方法在诊断美洲皮肤利什曼病（ATL）和直接从临床标本中快速鉴定利什曼物种方面的性能。
对来自阿根廷西北部的 63 名皮肤或黏膜病变患者进行 ATL 诊断方案，包括临床检查、利什曼素皮肤试验和皮肤刮片的显微镜检查。此外，我们还对从病变处刮取的标本直接提取的 DNA 进行 PS-PCR。
63 例患者中，44 例被归类为 ATL 病例，19 例为非 ATL 病例。皮肤刮片显微镜分析和 PS-PCR 的诊断敏感性分别为 70.5%和 81%。当并行进行这两种测试时，该参数显著增加至 97.6%（p=0.0018）。另一方面，组合的特异性分别为 100%、84.2%和 83.3%（p＞0.05）。通过 PS-PCR 分析，我们成功鉴定了 44 例 ATL 病例中的 31 例利什曼物种。28 例（90.3%）为 L.（V.） braziliensis 引起，2 例（6.5%）为 L.（V.）guyanensis 引起，1 例（3.2%）为 L.（V.）panamensis 引起。
通过将皮肤刮片检查与 PS-PCR 分析相结合，显著提高了 ATL 诊断的效果。我们的策略使我们能够以高准确率诊断出 70.5%的病因种属的 ATL，此外，我们还诊断出两例由 L.（V.）braziliensis 引起的播散性皮肤型病例和一例由 L.（V.）panamensis 感染引起的皮肤型病例，这两种发现均为阿根廷首次报道。
