Alveoler ekinokokkozun serolojik tanısında EgHF, Em2 ve EmII/3-10 antijenleri ile hazırlanan ELISA yöntemlerinin tanısal etkinliğinin değerlendirilmesi
Küçük Resim Yok
Tarih
2014
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Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Alveoler ekinokokkoz (AE), insanda Echinococcus multilocularis larvasının neden olduğu ölümcül paraziter hastalıklardan biri olup, özellikle kuzey yarımküredeki birçok ülkede önemli bir halk sağlığı sorunudur. Ülkemizdeki yaşam koşulları ve halkımızın alışkanlıklarıyla parazitin hayat döngüsü arasındaki etkileşim dikkate alındığında, hastalığın bugüne kadar, büyük çoğunluğu Doğu Anadolu bölgesinden bildirilen olgu serilerinden daha yaygın olduğu düşünülmektedir. AE’nin tanısında, dünyada başarıyla kullanılan özgüllüğü yüksek serolojik tanı yöntemlerinin ülkemizde uygulanmıyor olması, radyolo- jik olarak karaciğer lezyonları saptanan hastalarda hatalı malignensi tanılarına yol açmaktadır. Bu çalışmada, AE’nin serolojik tanısında, üç farklı antijen (EgHF, Em2, EmII/3-10) kullanılarak hazırlanan laboratuvar yapımı ELISA testlerinin tanısal etkinliklerinin araştırılması amaçlanmıştır. Çalışmamızda, testlerin duyarlılık ve özgüllüğünü değerlendirmek amacıyla, Bern Üniversitesi Parazitoloji Enstitüsünden sağlanan, tamamı klinik ve parazitolojik ve/veya histopatolojik olarak doğrulanmış, 10 farklı helmint ile enfekte (E.multilocularis, E.granulosus, Taenia solium, Wuchereria bancrofti, Strongyloides stercolaris, Ascaris lumbricoides, Toxocara canis, Trichinella spiralis, Fasciola hepatica, Schistosoma haematobium) 10’ar hasta olmak üzere toplam 100 hastadan alınan serum örnekleri kullanılmıştır. Antijen olarak kullanılan EgHF (E.granulosus hydatid fluid antigen) laboratuvarımızda kistik ekinokokkozlu koyun karaciğer kist sıvılarından hazırlanmış; Em2 (E.multilocularis metacestode-purified laminated layer antigen) ve EmII/3-10 (E.multilocularis recombinant protoscolex tegument antigen) ise Bern Üniversitesi Parazitoloji Enstitüsünden sağlanmıştır. Düz tabanlı ELISA plakları; çukur başına antijen konsantrasyonu EgHF, Em2 ve EmII/3-10 için sırasıyla 2.5 ?g, 1 ?g ve 0.18 ?g olacak şekilde kaplanmış ve EgHF-ELISA, Em2-ELISA ve EmII/3-10-ELISA yöntemleri tüm serumlara uygulanmıştır. Her üç test için belirlenen eşik değerinin (negatif kontrollerin OD ortalaması+2 SD) üstünde reaksiyon veren örnekler pozitif kabul edilmiştir. Çalışmada, EgHF, Em2 ve Em2II/3-10 antijenleri ile uygulanan ELISA yöntemlerinin duyarlılık değerleri sırasıyla %100, %90 ve %90; özgüllük değerleri ise sırasıyla %63, %91 ve %91 olarak hesaplanmıştır. Em2-ELISA ve EmII/3-10- ELISA ile saptanan pozitiflikler birlikte değerlendirildiğinde ise özgüllüğün %96’ya yükseldiği izlenmiştir. Bu verilere göre, AE’nin serolojik tanısı için üç farklı antijenin kullanıldığı ELISA testlerinin birlikte uygulanması halinde, yüksek duyarlılık (EgHF-ELISA ile %100) ve özgüllüğün (Em2-ELISA + EmII/3-10- ELISA ile %96) sağlanacağı görülmektedir. Sonuç olarak, AE açısından endemik olan ülkemizde, büyük ölçüde görüntüleme yöntemleriyle tanımlanan AE’nin erken ve doğru tanısında, Em2-ELISA ve EmII/3- 10-ELISA gibi özgüllüğü yüksek serolojik yöntemlerin güvenle kullanılabileceği ve radyolojik verilere önemli katkıda bulunacağı kanısına varılmıştır.
Alveolar echinococcosis (AE), caused by larva stage of Echinococcus multilocularis, is one of the lethal parasitic diseases of man and a major public health problem in many countries in the northern hemi- sphere. When the living conditions and habits in Turkey were considered in terms of relation with the life cycle of the parasite, it was suggested that AE has been much more common than reported mainly from the Eastern Anatolia region of Turkey. Since in vitro serologic diagnosis tests with high specificity for AE have not been used in our country, most of the cases with liver lesions were misdiagnosed by radiological investigations as malignancies. The aim of this study was to evaluate the diagnostic value of the in-house ELISA methods developed by using three different antigens (EgHF, Em2, EmII/3-10) in the serological diagnosis of AE. The study samples included a total of 100 sera provided by Bern University Parasitology Institute where samples were obtained from patients with helminthiasis and all were confirmed by clinical, parasitological and/or histopathological means. Ten samples from each of the cases infected by E.multilocularis, E.granulosus, Taenia solium, Wuchereria bancrofti, Strongyloides stercolaris, Ascaris lumbricoides, Toxocara canis, Trichinella spiralis, Fasciola hepatica and Schistosoma hae- matobium were studied. In the study, EgHF (E.granulosus hydatid fluid) antigens were prepared in our laboratory from the liver cyst fluids of sheeps with cystic echinococcosis, however Em2 (E.multilocularis metacestode-purified laminated layer) and EmII/3-10 (E.multilocularis recombinant protoscolex tegu- ment) antigens were provided by Bern University Parasitology Institute. Flat bottom ELISA plates were covered with EgHF, Em2 and EmII/3-10 antigens in the concentrations of 2.5 μg, 1 μg and 0.18 μg per well, respectively, and all sera were tested by EgHF-ELISA, Em2-ELISA and EmII/3-10-ELISA methods. For each tests, the samples which were reactive above the cut-off value (mean OD of negative controls+2 SD) were accepted as positive. The sensitivity of the ELISA tests performed with EgHF, Em2 and Em2II/3- 10 antigens were estimated as 100%, 90% and 90%, respectively, whereas the specificity were 63%, 91% and 91%, respectively. When Em2-ELISA and EmII/3-10-ELISA tests were evaluated together, the specificity increased to 96%. Our data indicated that the highest sensitivity (100% with EgHF-ELISA) and specificity (96% with Em2-ELISA + EmII/3-10-ELISA) for the serodiagnosis of AE can be achieved by the combined use of the ELISA tests with three different antigens. It was concluded that the early and accurate diagnosis of AE in our country which is endemic for that disease, could be supported by the use of highly specific serological tests such as Em2-ELISA ve EmII/3-10-ELISA contributing radiological data.
Alveolar echinococcosis (AE), caused by larva stage of Echinococcus multilocularis, is one of the lethal parasitic diseases of man and a major public health problem in many countries in the northern hemi- sphere. When the living conditions and habits in Turkey were considered in terms of relation with the life cycle of the parasite, it was suggested that AE has been much more common than reported mainly from the Eastern Anatolia region of Turkey. Since in vitro serologic diagnosis tests with high specificity for AE have not been used in our country, most of the cases with liver lesions were misdiagnosed by radiological investigations as malignancies. The aim of this study was to evaluate the diagnostic value of the in-house ELISA methods developed by using three different antigens (EgHF, Em2, EmII/3-10) in the serological diagnosis of AE. The study samples included a total of 100 sera provided by Bern University Parasitology Institute where samples were obtained from patients with helminthiasis and all were confirmed by clinical, parasitological and/or histopathological means. Ten samples from each of the cases infected by E.multilocularis, E.granulosus, Taenia solium, Wuchereria bancrofti, Strongyloides stercolaris, Ascaris lumbricoides, Toxocara canis, Trichinella spiralis, Fasciola hepatica and Schistosoma hae- matobium were studied. In the study, EgHF (E.granulosus hydatid fluid) antigens were prepared in our laboratory from the liver cyst fluids of sheeps with cystic echinococcosis, however Em2 (E.multilocularis metacestode-purified laminated layer) and EmII/3-10 (E.multilocularis recombinant protoscolex tegu- ment) antigens were provided by Bern University Parasitology Institute. Flat bottom ELISA plates were covered with EgHF, Em2 and EmII/3-10 antigens in the concentrations of 2.5 μg, 1 μg and 0.18 μg per well, respectively, and all sera were tested by EgHF-ELISA, Em2-ELISA and EmII/3-10-ELISA methods. For each tests, the samples which were reactive above the cut-off value (mean OD of negative controls+2 SD) were accepted as positive. The sensitivity of the ELISA tests performed with EgHF, Em2 and Em2II/3- 10 antigens were estimated as 100%, 90% and 90%, respectively, whereas the specificity were 63%, 91% and 91%, respectively. When Em2-ELISA and EmII/3-10-ELISA tests were evaluated together, the specificity increased to 96%. Our data indicated that the highest sensitivity (100% with EgHF-ELISA) and specificity (96% with Em2-ELISA + EmII/3-10-ELISA) for the serodiagnosis of AE can be achieved by the combined use of the ELISA tests with three different antigens. It was concluded that the early and accurate diagnosis of AE in our country which is endemic for that disease, could be supported by the use of highly specific serological tests such as Em2-ELISA ve EmII/3-10-ELISA contributing radiological data.
Açıklama
Anahtar Kelimeler
Mikrobiyoloji
Kaynak
Mikrobiyoloji Bülteni
WoS Q Değeri
Scopus Q Değeri
Cilt
48
Sayı
3
