Gwóźdź J M, Reichel M P, Murray A, Manktelow W, West D M, Thompson K G
Department of Veterinary Pathology and Public Health, Massey University, Palmerston North, New Zealand.
Vet Microbiol. 1997 Sep;57(2-3):233-44. doi: 10.1016/s0378-1135(97)00136-3.
A direct polymerase chain reaction (PCR) test was applied to DNA extracted from blood, liver, ileocecal lymph node and ileum from twelve ewes in poor condition with histologically confirmed paratuberculosis and ten clinically normal sheep which had no evidence of paratuberculosis. The assay was compared with four serological tests: complement fixation test (CFT), gel diffusion test (AGID) and two enzyme-linked immunosorbent assays (ELISA). The PCR detection rate of Mycobacterium avium subsp. paratuberculosis, when results of single tests were interpreted in duplicate, was 72% for ileocecal lymph node, 90% for liver, and 100% for ileum in sheep with confirmed paratuberculosis. A single PCR test detected the target DNA in 66% of 0.5 ml blood samples. Sensitivities of serological tests compared with histological diagnosis were: 33% for CFT, 66% for AGID, 75% for the Central Animal Health Laboratory (CAHL) ELISA, and 83% for the 'modified' Commonwealth Serum Laboratories (CSL) ELISA. The PCR assay gave no positive reaction in samples collected from 10 sheep considered to be free of paratuberculosis. Similarly, all four serological tests were also 100% specific. The results raise some hope for the development of a PCR-based test using liver biopsy specimens, or possibly blood, in the diagnosis of paratuberculosis in sheep.
对12只状况不佳且经组织学确诊患有副结核病的母羊以及10只无副结核病迹象的临床正常绵羊的血液、肝脏、回盲部淋巴结和回肠提取的DNA进行了直接聚合酶链反应（PCR）检测。该检测方法与四种血清学检测方法进行了比较：补体结合试验（CFT）、凝胶扩散试验（AGID）和两种酶联免疫吸附试验（ELISA）。在对确诊患有副结核病的绵羊进行检测时，若对单次检测结果进行重复解读，鸟分枝杆菌副结核亚种的PCR检测率在回盲部淋巴结中为72%，在肝脏中为90%，在回肠中为100%。单次PCR检测在66%的0.5毫升血液样本中检测到了目标DNA。与组织学诊断相比，血清学检测的灵敏度分别为：CFT为33%，AGID为66%，中央动物卫生实验室（CAHL）ELISA为75%，“改良”联邦血清实验室（CSL）ELISA为83%。PCR检测在从10只被认为无副结核病的绵羊采集的样本中未出现阳性反应。同样，所有四种血清学检测的特异性也均为100%。这些结果为开发基于PCR的检测方法（使用肝脏活检标本或可能使用血液）用于诊断绵羊副结核病带来了一些希望。
