Ballam L D, Mendall M A, Asante M, Morris J, Strachan D P, Whincup P H, Cook D G
GEMS Division, St George's Hospital Medical School, London, UK.
J Clin Pathol. 2000 Apr;53(4):314-7. doi: 10.1136/jcp.53.4.314.
The salivary diagnosis of Helicobacter pylori infection offers attractive possibilities for the epidemiological study of infection in children. Salivary enzyme linked immunosorbent assay (ELISA) is less reliable then serum ELISA, owing to variable transudation of immunoglobulin. In addition, children are more difficult to study because of lower specific serum antibody concentrations to H pylori. The performance of salivary western blotting in comparison with serum western blotting and serum ELISA was investigated in school children.
Paired serum and saliva specimens were obtained from 669 [corrected] school children aged 9-11 in 10 British towns. All saliva and serum specimens were first analysed by ELISA; subsequently, western blotting of both specimens was performed on 31 and 34 specimens, respectively, to establish the criteria for positivity for western blotting. The remaining 121 specimens were then tested blindly and saliva was compared with the serum.
The sensitivity and specificity of salivary ELISA in the 669 [corrected] specimens was 32 of 50 (64%) and 530 of 619 (86%) [corrected], respectively, when compared with serum ELISA. The western blotting validation was performed on 28 subjects with positive serum and positive salivary ELISA, 28 saliva positives with negative serum, 16 saliva negatives with positive serum, and 50 doubly negative subjects. Compared with serum western blots, the sensitivity and specificity of salivary western blots was 38 of 47 (81%) and 68 of 75 (91%), respectively. Using serum ELISA as the gold standard, the sensitivity and specificity were 32 of 44 (73%) and 72 of 78 (92%), respectively, the specificity being significantly higher than salivary ELISA (p < 0.001).
Salivary western blotting for IgG is useful in the diagnosis of H pylori infection and is superior to ELISA. It also permits the identification of pathogenic strains.
幽门螺杆菌感染的唾液诊断为儿童感染的流行病学研究提供了有吸引力的可能性。由于免疫球蛋白渗出量的变化，唾液酶联免疫吸附测定（ELISA）不如血清ELISA可靠。此外，由于儿童对幽门螺杆菌的特异性血清抗体浓度较低，对其进行研究更加困难。本研究在学龄儿童中比较了唾液免疫印迹法与血清免疫印迹法及血清ELISA的性能。
从英国10个城镇的669名9至11岁学龄儿童中获取配对的血清和唾液标本。所有唾液和血清标本首先通过ELISA进行分析；随后，分别对31份和34份标本进行了两种标本的免疫印迹，以确定免疫印迹阳性标准。然后对其余121份标本进行盲测，并将唾液与血清进行比较。
与血清ELISA相比，669份标本中唾液ELISA的敏感性和特异性分别为50份中的32份（64%）和619份中的530份（86%）。对28名血清阳性且唾液ELISA阳性的受试者、28名唾液阳性但血清阴性的受试者、16名唾液阴性但血清阳性的受试者以及50名双阴性受试者进行了免疫印迹验证。与血清免疫印迹相比，唾液免疫印迹的敏感性和特异性分别为47份中的38份（81%）和75份中的68份（91%）。以血清ELISA作为金标准，敏感性和特异性分别为44份中的32份（73%）和78份中的72份（92%），特异性显著高于唾液ELISA（p < 0.001）。
IgG唾液免疫印迹法对幽门螺杆菌感染的诊断有用，且优于ELISA。它还能识别致病菌株。
