DNA-not i and EBER1-RNA immunohistochemical stains of EB virus-induced tonsillar lesions

• Published in: Otolaryngology-head and neck surgery 2004-08, Vol.131 (2), p.P286-P286
• Main Authors: Kurihara, Rika, Sato, Yu-ichi, Nakayama, Meijin, Yao, Kazuo, Okamoto, Makito
• Format: Article
• Language: English
• ISSN: 0194-5998; 1097-6817
• DOI: 10.1016/j.otohns.2004.06.615

Objectives: EB virus infection is known to associate with tonsillar malignant lymphoma and acute tonsillitis, such as infectious mononucleosis. The accurate histopathological diagnosis of these lesions by HE stain alone is difficult. DNA-Not I and EBER1-RNA immunohistochemical stains are used to assist the definite diagnosis of EB virus induced tonsillar lesions. Methods: EBER1-RNA stain detects the RNA of EB virus at its latent phase. While DNA-Not I stain detects the DNA of EB virus at its active phase. A total of 13 specimens were evaluated (4 EB virus induced tonsillitis; 3 tonsillar DLBL malignant lymphoma; 3 chronic tonsillitis; and 3 normal tonsils). Rapid in situ hybridization technique was utilized for staining. Results: Among the 4 cases of EB virus induced tonsillitis, 2 showed positive stains of both DNA-Not I and EBER1-RNA stains and 2 manifested positive stain only in EBER1-RNA. The former 2 cases showed drastic clinical courses were diagnosed as infectious mononucleosis. Among the 3 tonsillar DLBL malignant lymphoma, both stains were negative. All other specimens also showed negative stains. Conclusion: DNA-Not I and EBER1-RNA immunohistochemical stains are positive when the EB virus infection is relatively active such as with infectious mononucleosis. Positive stain was not common with DLBL malignant lymphoma. Both stains are useful for the differential diagnosis between EB virus induced lesions, especially combined with a careful observation of the clinical symptoms.