Hamdan Ibrahim Al MOHAMMAD, Magdy Hassan BALAHA, Tarek Tawfik AMIN, Eman El Masry El DAMARANY, Ashraf DWEDAR

The accuracy of IgG avidity for detection of acute toxoplasmosis among pregnant saudi women

AMAÇ: Akut toksoplazmanın teşhisi immunoglobulin M’in (IgM) varlığına bağlıdır ancak, bazı durumlarda IgM varlığı uzun süre devam edebilmektedir. Bu çalışmanın amacı, erken gebelikte Akut Toksoplazmoz Tespitininde IgG aviditesinini rolü ve tutarlılığının değerlendirilmesidir. METOD: Çalışmaya 160 kadın katılmıştır. Kadınlardan alınan serumlarda anti-toksoplasma IgG ve IgM ile Ig G aviditesi ELIZA yöntemi ile analiz edilmiştir. Seçilen örnek gruplarında PCR kullanılarak doğrulama yapılmıştır. Bu çalışma Suudi Arabistan’ın Kral Faysal Üniversitesi Tıp Fakültesi’nde Ocak 2008, Nisan 2009 tarihleri arasında gerçekleştirilmiştir. BULGULAR: Negatif IgM ve düşük avidite taspit edilen 32 vakanın yanında15 vakada, pozitif IgM ve yüksek avidite tespit edilmiştir. 16 vakada ise pozitif IgG’nin yanında düşük avidite tespit edilmiştir. Pozitif IgM tespit edilenlerle ilgili olarak düşük avidite tutarlılığının duyarlılığı, seçiciliği, positif ve negatif prediktif değeri ve olabilirlik oranı sırasıyla; 77.0%, 51.5%, 64.0%, 66.7% ve 1.58 bulunmuştur. SONUÇ: IgM’in negative bulunması, toxoplazma enfeksiyonunu dışlamamaktadır. IgG’nin pozitif olması ise daha önceki enfeksiyonlardan kaynaklanmış olabilmektedir. IgG avidite testleri daha önce geçirilmiş enfeksiyonların hassas olarak dışlanmasına yardım edebilmektedir

Hamile suudi kadınlarda akut toksoplazmoz tespiti için kullanılan IgG aviditesinin tutarlılığı

AIM: The diagnosis of acute toxoplasmosis depends on the presence of immunoglobulin M (IgM), but it may persist for a long time in some cases. The objective of this study was to determine the role and accuracy of IgG avidity for the detection of acute Toxoplasmosis in early pregnancy. METHOD: The study included 160 women. Sera were screened for anti-Toxoplasma IgG and IgM and for IgG-avidity using ELIZA. PCR was done for confirmation in selected group of specimens. This study was performed at the College of Medicine, King Faisal University, Saudi Arabia from January 2008 through April 2009. RESULTS: 32 cases of low avidity were negative IgM while 15 cases of high avidity were positive IgM. 16 cases of low avidity were positive IgG. The accuracy of low avidity in relation to positive IgM revealed a sensitivity, specificity, positive predictive value, negative predictive value and likelihood ratio of 77.0%, 51.5%, 64.0%, 66.7% and 1.58 respectively. The accuracy of low IgG avidity in comparison with PCR demonstrated 91%, 45.7%, 60.4% and 84.2% respectively. CONCLUSION: Negative IgM didn’t exclude recent Toxoplasma infection and positive IgG may be present with recent infection. IgG avidity testing help in accurate differentiation of recent infections.

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