Herpes simplex virus and Meniere's disease

OBJECTIVE/HYPOTHESIS: This study was designed to investigate the hypothesis that Meniere's disease is associated with herpes simplex virus (HSV) reactivation in the vestibular ganglion. STUDY DESIGN: Case control study. METHODS: Vestibular ganglia were obtained from archival surgical pathology specimens from patients undergoing vestibular neurectomy for vertigo caused by Meniere's disease. All patients met criteria for classification as definite Meniere's disease according to American Academy of Otolaryngology/Head and Neck Surgery (AAO-HNS) criteria. Control specimens were obtained from willed body donors. Sections from each ganglion were studied for prevalence of viral DNA using a nested polymerase chain reaction designed to amplify the HSV DNA polymerase gene. Quantitative analysis determined the number of viral copies per standard unit of ganglionic DNA. RESULTS: HSV DNA was more prevalent in paraffin embedded ganglia from patients with Meniere's disease (100%) than in fresh-frozen control ganglia (81%) (P =.02). Fixation and paraffin embedding substantially reduced recovery of HSV virus in selected control specimens. Quantitative analysis found no correlation between viral copy number in control ganglia processed frozen versus formalin fixed and paraffin embedded. CONCLUSIONS: HSV is more commonly isolated from vestibular ganglia of patients with Meniere's disease than the general population. The routine histologic preparation of formalin fixation and paraffin embedding significantly altered the quantity of virus detected though not in a predictable manner. The study provides supportive evidence for a viral etiology in Meniere's disease.     

人疱疹病毒6型对EB病毒复制影响的研究

目的 探讨人疱疹病毒６型（ＨＨＶ－６）对ＥＢ病毒（ＥＢＶ）复制的影响。方法 用ＨＨＶ－６感染Ｒａｊｉ细胞和ＥＢＶ转化的淋巴细胞（ＬＣＬ），并用抗ＨＨＶ－６单克隆抗体（ＭＡｂ）作免疫萤光分析（ＩＦＡ）确定ＨＨＶ－６已感染这二种细胞。用抗ＥＢＶ人血清作ＩＦＡ观察ＥＢＶ抗原表达。结果 ＨＨＶ－６感染Ｒａｊｉ细胞后可见细胞病变效应（ＣＰＥ）；而ＬＣＬ未见ＣＰＥ。这二种细胞株用抗ＨＨＶ－６的ＭＡｂ作ＩＦＡ均     

Oropharyngeal kaposi sarcoma in related persons negative for human immunodeficiency virus

OBJECTIVES: Kaposi sarcoma (KS) is a vascular tumor that can affect the mucosa of the upper aerodigestive tract. Although KS is the most common malignancy in patients with acquired immunodeficiency syndrome, it is rare in immunocompetent persons. We describe an unusual presentation of KS in 2 related individuals and describe our attempts to determine whether oropharyngeal KS is associated with human herpesvirus 8 (HHV-8). METHODS: All relevant clinical and surgical information, including information on tumor histopathologic and human immunodeficiency virus (HIV) serologic tests, was abstracted from the patient charts and electronic databases. HHV-8 immunohistochemistry was performed on paraffin-fixed specimens. RESULTS: Both patient 1 and patient 2 (the nephew of patient 1) were referred for workup of a tonsillar mass that was pathologically confirmed to be KS. In each case, HIV serologic testing was negative, and a screening immunologic workup, including a quantitative natural killer cell count, a B- and T-lymphocyte count, and immunoglobulin analysis, also yielded findings that were within normal limits. Immunohistochemistry performed on 1 pathological specimen showed positive staining for the presence of HHV-8, the etiologic agent of KS. CONCLUSIONS: The presence of oropharyngeal KS in 2 related HIV-negative individuals supports a role for genetic factors in susceptibility to KS, a common exposure to an infectious agent such as HHV-8, or both. Whereas most KS cases in industrialized countries are associated with immunodeficiency, clinical and laboratory data do not suggest that either of the patients described in this report are immunodeficient. Their susceptibility to KS may be secondary to a subtle inherited defect in host resistance to HHV-8, or another unknown factor.     

The role of viruses in idiopathic peripheral facial palsy and cellular immune response

PURPOSE: The purpose of this study is to investigate the role of viruses on the idiopathic peripheral facial palsy and show the interaction of immune system. MATERIALS AND METHODS: The levels of immunoglobulin (Ig) G and IgM antibodies against to varicella-zoster virus (VZV), herpes simplex virus (HSV), cytomegalovirus (CMV), Ebstein-Barr virus (EBV), and mumps virus in venous blood taken from patients in the amount of 10 mL have been investigated by enzyme-linked immunosorbent assay method. Tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), and transforming growth factor-beta (TGF-beta) were also examined. Of lymphocyte subpopulation, antibodies of CD3(+), CD4(+), CD8(+), CD19(+), and CD16(+) plus 56(+) were analyzed. RESULTS: Ten of the patients had HSV-1 IgG; 1 of the patients IgM, 5 of the patients EBV IgG, 6 of the patients VZV IgG, 1 of the patients IgM, 9 of the patients mumps IgG, 1 of the patients IgM, and finally in 7 of the patients CMV IgG antibodies were obtained. It was found that CD4(+) cell and ratio of CD4(+)/CD8(+) lower and the percentage of the CD8(+) and CD16(+) plus 56(+) cells higher compared with the control group (P < .05). The levels of TNF-alpha were lower, whereas IFN-gamma and TGF-beta1 were higher. CONCLUSION: It may be concluded from these results that VZV, HSV-1, CMV, EBV, and mumps virus play a significant role in the etiology of idiopathic peripheral facial palsy and activate the cellular immunity.     

Klinische und histopathologische Charakterisierung oraler Leukoplakien bei Patienten mit HIV-Infektion

The aim of this study was to assess the prevalence of oral leukoplakia (OL) in HIV-positive patients and to evaluate the clinical and histopathological features and the presence of Candida hyphae and viral infections (HSV 1, 2, HPV, EBV and CMV) by immunocytochemical methods using mono- or polyclonal antibodies. A total of 269 HIV-seropositive patients, (222 men, median age 36.7 years and 47 women, median age 32 years) were registered. OL occurred in 20/269 (7.4%) patients (men, smokers, median age 38 years); the non-homogeneous form was observed in 11%. A lesional biopsy specimen was obtained from 8/20 patients. Specimens did not show signs of epithelial dysplasia. Candida hyphae were evident in 2/8 cases. Two patients tested positive for HPV and CMV; antibodies against EBV, HSV1 and 2 were negative. In conclusion, the prevalence of OL is comparatively high in this group of HIV-seropositive patients (7.4% vs. 0.9-2.2%). Moreover, the mean age of the study group at the time of diagnosis for OL was lower (38 years vs. 60 years).     

Parotid localized Castleman’s disease and HHV-8 infection: a case report

Castleman’s disease (CD) is an unusual massive proliferation of lymphoid tissue distinct in two clinical forms, localized and multicentric. The multicentric form has been related to human herpesvirus 8 (HHV-8), especially in HIV-infected patients, whereas the localized form of CD is still unrelated to viral pathogens. We report a case of a HIV-negative 16-year-old male referred to our hospital with a 12-month history of a painless swelling in his right parotid region. A parotidectomy was performed, and histological analysis evidenced a localized CD. The search for HHV-8 revealed an active virus infection. The patient was commenced on corticosteroid therapy and a follow-up was performed every 6 months. The patient was commenced on corticosteroid therapy and there has been no recurrence after 24 months. The authors report a case of localized parotid CD in a patient with evidence of an active HHV-8 infection. The results of this study does for the first time suggest an association between HHV-8 and localized CD in HIV-negative subjects.     

Epstein-Barr virus early ribonucleic acids as a diagnostic adjunct for relapsed metastatic tumors in patients with cured primary undifferentiated nasopharyngeal carcinoma

PURPOSE: Epstein-Barr virus (EBV) has been consistently shown to be associated with undifferentiated nasopharyngeal carcinoma (NPC). In this article, the authors attempt to detect Epstein-Barr virus in distant relapsed metastatic sites in undifferentiated NPC patients with cured primary cancer. MATERIALS AND METHODS: In situ hybridization (ISH) technique is a reliable method to detect EBV early RNAs (EBERs) within NPC cells. We used a nonisotopical ISH technique to examine the presence of EBERs in paraffin-embedded tissues obtained from 1 paired specimen of primary NPC and its metastatic counterpart at liver and 2 metastatic specimens of retroperitoneal lymph nodes and bone. RESULTS: All the primary lesions and the metastatic tumors of NPC with undifferentiated histology contained EBERs that could be clearly detected in the nuclei of cancer cells. CONCLUSIONS: This article shows that EBERs can be successfully detected in cells of the distant relapsed metastatic sites. These results suggest that this nonisotopical ISH method of EBERs can be potentially used to diagnose NPC patients developing distant relapsed metastatic lesions with cured primary cancer early. It can offer quick information as to institute suitable salvage chemotherapy for these patients.     

EB病毒基因BARF1在鼻咽癌中的表达及其意义

目的 EB病毒与鼻咽癌(特别是低分化鳞癌)密切相关。BARF1基因是EBV裂解期中的早期基因，本研究通过检测BARF1基因在鼻咽癌组织中的表达，希望能进一步揭示EB病毒与鼻咽癌的关系及致癌的可能机制。方法 对经病理确诊的47例鼻咽低分化鳞癌病人分别取癌组织、癌旁组织及相对正常鼻咽黏膜和13例其他头颈部恶性肿瘤癌组织及8例正常人鼻咽黏膜组织(均证实有EB病毒潜伏感染)，采用巢式-PCR技术检测BARF1在这些组织中的表达情况。结果 鼻咽癌组织BARF1基因表达率为91．5％(43／47)，其中39例相对强表达，4例弱表达；癌旁组织BARF1基因表达率为46．8％(22／47)，其中儿例相对强表达，儿例弱表达；相对正常黏膜BARF1基因表达率为6．4％(3／47)，3例均为弱表达；携带EB病毒的其他头颈部恶性肿瘤组织、正常人鼻咽黏膜组织均未检测到：BARY1基因表达。结论 从相对正常鼻咽黏膜到癌旁组织再到鼻咽癌组织BARF1基因的表达趋势为从不表达到表达，从弱表达到强表达。说明EB病毒与鼻咽癌的发生确实存在密切相关性；提示启动BARF1基因的表达有可能是EB病毒致鼻咽癌的重要条件之一。     

Detection of Epstein-Barr virus and subsets of lymphoid cells in adenoid tissue of children under 2 years of age

Epstein-Barr virus (EBV) has been closely associated with undifferentiated nasopharyngeal carcinoma (NPC) and T/NK nasal non Hodgkin lymphoma. Nevertheless, the presence of EBV in non neoplastic lymphoid tissue of the nasopharynx has been rarely investigated. In a previous study by our group, using in situ hybridization to detect EBV in adenoids of children (2-13 years old) resected because of nasal obstruction due to hypertrophy, we found EBV genome in 72% of the cases. It was now intended to study the frequency of EBV expression in adenoids from children that underwent surgical removal, belonging to a lower age group (1-2 years old). It was also intended to establish which lymphoid subsets are involved in this infection. Adenoidal paraffin sections from 21 patients aged 1-2 years old (mean 1.6 years), 15 males and six females were submitted to double labeling: in situ hybridization with EBER 1/2 probes to detect EBV and immunohistochemistry to determine the lymphocyte typing of EBV-positive cells (CD20 for B-lymphocytes, CD3 for T-lymphocytes and CD56 and CD57 for NK-cells). Among 21 patients, seven showed positive lymphoid cells for EBV (33%). In almost all cases, EBV-positive cells were also CD20-positive. Some EBV-positive cells showed no labeling with any of the lymphoid markers, but in no instance they were positive for CD3, CD56 or CD57. This study confirms the preferential infection of B-lymphocytes by EBV, which in some instances can down regulate the expression of CD20.     

Detection of HHV-8 and HPV in laryngeal carcinoma

OBJECTIVE: In this study we aimed to investigate the presence of human herpesvirus 8 (HHV-8) and human papillomavirus (HPV) in laryngeal carcinoma. MATERIALS AND METHODS: Fifty patients operated on because of laryngeal carcinoma were included in the study. Forty-seven had squamous cell carcinoma (SCC) whereas three had verrucous carcinoma. Fresh tumoral tissues, or tumoral tissues obtained from archival paraffin-embedded blocks, were examined. HHV-8 DNA and HPV DNA were detected using polymerase chain reaction (PCR) and viral genotypes of HPV were determined via the hybrid capture method. The presence of HHV-8 DNA and HPV DNA were also investigated in normal appearing laryngeal tissue collected from 50 cadavers at autopsy. RESULTS: HPV DNA was detected in seven patients (7/50; 14%) (5 out of 47 patients with SCC (5/47; 10.6%) and two out of three patients with verrucous carcinoma). HHV-8 DNA was detected in five patients and they all had SCC (5/47; 10.6%). One case had both HHV-8 and HPV DNA. None of the control samples from cadavers harbored HHV-8 DNA, or HPV DNA. There was a statistically significant correlation between HHV-8 DNA and HPV DNA positivity and laryngeal SCC (Fisher exact test; p=0.023 for each). No statistically significant correlations were found between the presence of HHV-8 and/or HPV and age, gender, tumor stage, differentiation, the site of the tumor, smoking and alcohol use. CONCLUSIONS: The findings of the present study suggest that beside HPV, HHV-8 might have a role in laryngeal carcinogenesis. Further investigations are necessary to clarify the exact role of these viruses in laryngeal carcinoma.     

Detection of viral DNA in the endolymphatic sac in Ménière's disease by in situ hybridization

The main purpose of this study is to search for a viral etiology in Ménière's disease by examining the presence or absence of herpes family virus DNA in the endolymphatic sac (ES) using the in situ hybridization method. This was a prospective study with the ES from 10 patients with Ménière's disease and from 7 control cases without any pre-mortem ear diseases except a case of acoustic tumor. These 10 patients underwent the ES surgery. The presence of herpes family virus DNA, such as herpes simplex virus types 1 and 2 (HSV1&2), varicella-zoster virus (VZV), Epstein-Barr virus (EBV) and human cytomegalovirus (CMV), was examined using the in situ hybridization method. Serum antibody titers against these viruses just before the ES surgery were studied in these patients. Of the 10 specimens from the patients with Ménière's disease, 7 were positive for VZV, 4 for EBV, 1 for CMV and none for HSV1&2, although the serum antibody titers against these viruses did not show any significant elevation in these patients just before the ES surgery. This result suggests that the viral DNA in the ES is inactive and is present in a latent form. From the statistical analysis, it can be postulated that VZV infection in early childhood may reach the ES and play a role in the pathogenesis of Ménière's disease (p = 0.0235). The double infection with both VZV and EBV tended to be another candidate for the pathogenesis of Ménière's disease (p = 0.0557).     

Epstein-Barr virus detected in a head and neck squamous cell carcinoma cell line derived from an immunocompromised patient

BACKGROUND: DNA tumor viruses potentially play a role in the development of squamous cell carcinoma of the head and neck (SCCHN). Human papillomavirus is found in up to 50% of SCCHN specimens, and Epstein-Barr virus (EBV) has been detected in nasopharyngeal carcinoma, Burkitt lymphoma, and other lymphomas. However, the role of EBV in nonnasopharyngeal SCCHN has not been thoroughly investigated. METHODS: Twenty-one SCCHN cell lines derived from tumors of various subsites were used to screen for EBV DNA as well as latent viral protein expression. The method of EBV DNA detection was polymerase chain reaction with 3 independent primer sets from distinct regions of the genome. Expression of the viral protein EBNA-1, critical for the maintenance of the viral episome, was monitored by immunofluorescence using an antibody specific for EBNA-1. In addition, 12 paraffin-embedded tumor specimens and adjacent normal tissues were analyzed by polymerase chain reaction. These tumor specimens were further characterized by immunohistochemistry with the use of a mouse monoclonal antibody that recognizes EBNA-1. RESULTS: Little or no EBV DNA was detected in 20 of 21 cell lines or in any of the tumor specimens, while detecting approximately 40 genome copies in a control reaction. Accordingly, these cell lines and specimens were negative for EBNA-1 expression. In 1 cell line derived from an immunosuppressed patient, EBV DNA was detected, and on further examination a small percentage of cells expressed EBNA-1 as shown by immunofluorescence. CONCLUSIONS: Although EBV may not be a major cofactor contributing to the proliferation of SCCHN, the limited initial evidence suggests that EBV may be involved in development of SCCHN in immunosuppressed patients.     

Herpesvirus type 1-8 in sinus aspirates from HIV-infected patients and immunocompetent individuals

Sinusitis is frequently occurring in HIV-infected patients, but in a substantial number of cases the etiology is unknown. The purpose of this study was by PCR 1) to determine the prevalence of the eight human herpesviruses in sinus aspirates from 24 HIV-positive/AIDS patients with sinusitis 2) to relate the presence of herpesvirus DNA to clinical and immunological parameters and 3) to compare the prevalence of herpesvirus DNA in sinus aspirates from HIV-infected patients with the prevalence observed in 50 immunocompetent patients with sinusitis. DNA from HSV-1, EBV, CMV and HHV-8 was detected in 8 (33%) of the sinus aspirates from HIV-infected patients. In the immunocompetent patients, one of the herpesviruses, HHV-6, was found in one sinus aspirate. These data indicate that herpesviruses are frequently found in sinus aspirates from HIV-infected patients with sinusitis, whereas they do not seem to be related to clinical signs of sinusitis in immunocompetent individuals. The cause of these discrepancies may be due to uncontrolled reactivation of herpesviruses, which is known to occur in immunocompromised individuals. It remains to be established whether the herpesviruses play a pathogenic role in the development of sinusitis in HIV-infected patients.     

Prognostic factors in major salivary gland cancer

OBJECTIVE: To identify features of major salivary gland cancers that are prognostic for disease-free survival. STUDY DESIGN: A retrospective study of 78 patients with major salivary gland cancer (64 parotid and 14 submandibular gland) who underwent surgery for definitive treatment from 1976 to 1996. A select group of patients also received adjuvant radiation (56%) and/or chemotherapy (13%). METHOD: Clinical and pathological risk factors were obtained from patients' charts and pathology reports. Age, gender, tumor site, T-stage, facial paralysis, histologic neck involvement, perineural invasion, and cancer grade were analyzed with respect to disease-free survival. The role of adjuvant treatment in terms of clinical outcome was also investigated. RESULTS: In our series, the 5-year disease-free survival was 65%. Examining clinical and histologic features one at a time, we found poorer prognosis was associated with submandibular tumors compared with parotid (P =.02), higher T-stage (P =.001), positive cervical nodes (P <.001), perineural invasion (P =.002), and high-grade or adenoid cystic tumors (P =.002). A multivariable analysis indicated that positive lymph nodes (P =.07) and perineural invasion (P =.03) were important histologic predictors of shorter disease-free survival. Receipt of both adjuvant radiation and cisplatin-based chemotherapy (P =.05) was an independent predictor of longer disease-free survival. CONCLUSION: Our study indicated that the presence of positive lymph nodes and perineural invasion is important independent predictors of disease-free survival. Our limited data also suggest that adjuvant chemotherapy and radiation therapy may improve disease-free survival.     

Clinicopathological features of Epstein-Barr virus-associated nasal T/NK cell lymphomas in southern Japan

OBJECTIVE: Nasal T/natural killer cell lymphomas (NTCL) are highly prevalent among Oriental populations. However the characteristic immunophenotype of NTCL is still controversial and it can be difficult to make a firm histologic diagnosis of malignancy. Therefore, 14 cases of NTCL in patients from southern Japan were evaluated for clinicopathological features and immunophenotypic status. Furthermore, the genetic variations in the latent membrane protein 1 (LMP-1) gene of Epstein-Barr virus (EBV)-related NTCL were evaluated. METHODS: Biopsy specimens were fixed in formalin and embedded in paraffin before examination using in situ hybridization for EBV-encoded RNA-1 (EBER-1) as well as immunohistochemical staining for CD3, CD3epsilon, CD4, CD8, CD43, CD45RA, and CD45RO. To detect genetic variations, single-strand conformation polymorphism (SSCP) analysis and DNA sequencing were applied. RESULTS: Clinically, 14 cases were divided into two groups. The first group consisting of eight patients showed good prognosis. The other group consisting of six patients showed poor prognosis. The vast majority of neoplastic cells in NTCL were EBER-1 positive. These cells did not express CD4, CD8, or CD45RA, but often expressed CD43 and CD45RO. In addition, they were negative for CD3 when stained with a mouse monoclonal antibody but stained for CD3epsilon when a rabbit polyclonal was used. The 3'-terminal of LMP-1 gene of seven cases were amplified and all of them have 30 base pair (bp) deletion. CONCLUSION: NTCL are a heterogeneous mix of cell types although EBV-associated NTCL in patients from southern Japan appear to originate from natural killer cells rather than T cells, and also prognosis is variable and not always poor. The ability to make a firm diagnosis can be enhanced through the combined use of in situ hybridization and immunohistochemistry. High prevalence of the 30-bp deletions of the LMP-1 gene in EBV-related NTCL may also reflect the prevalence of the deletion variant in the normal population in Japan.     

Untersuchungen zur Persistenz von Epstein-Barr-Virus

Summary Primary infection with Epstein-Barr virus is followed by a lifelong carrier state. Virus can be isolated from the saliva for many months or years.It was not clear, however, whether circulating lymphocytes which are enriched in the oropharyngeal tissue may occasionally enter a lytic circle or if if EBV is produced in a specific site of the body resembling the behaviour of Marek's disease Herpes virus.In situ hybridization with frozen section from tonsils, parotid glands and other tissues revealed that EBV genomes are present in the tissue of the parotid gland of healthy persons. The data from in situ hybridizations could be confirmed using stringent reassociation kinetic.Isolation of EBV from the ducts of the parotid gland has been reported during the course of our work by Morgan et al. (1979). This finding is in perfect agreement with our data.     

Coinfection by multiple strains of Epstein-Barr virus in infectious mononucleosis in immunocompetent patients

OBJECTIVE: A molecular study of Epstein-Barr virus (EBV)-induced infectious mononucleosis (IM) was performed. The presence of a 30-bp deletion on the latent membrane protein-1 (LMP-1) oncogene from EBV in Caucasian IM patients was evaluated. MATERIAL AND METHODS: Peripheral blood mononuclear cells were obtained from 27 IM patients and 18 adenoids, 28 tonsils and 16 EBV-related reactive lymphadenitis specimens were used as controls. DNA isolation, EBV polymerase chain reaction (PCR) and LMP-1 oncogene PCR analysis were performed. RESULTS: The 30-bp deletion on LMP-1 was identified in 29.6% of IM patients, but was always seen in conjunction with full-length LMP-1. Although the LMP-1-deleted strain seemed to be more prevalent in IM (29.6%) and EBV-related reactive lymphadenitis (37.5%,) than in adenoid (0%) or tonsil specimens (21.4%), these differences were not significant (p > 0.05; chi2). Thus, a 30-bp deletion on LMP-1 was present in almost a third of Caucasian IM patients. CONCLUSION: The finding of coinfections in IM patients confirms that primary infection by more than one EBV strain is possible.     

应用PCR技术检测分泌性中耳炎病人中耳积液病毒基因

目的：评价分泌性中耳炎中耳积液中多种病毒、支原体、衣原体及细菌的感染率。方法：应用PCR技术检测48例（55耳）中耳积液中腺病毒（ADV）,EB病毒（EBV）,呼吸道合胞病毒（RSV）,肺炎支原体（MP）及沙眼衣原体（CT）基因,并对中耳积液行常规细菌培养。结果：78．2％患者发病初期有感冒病史。病原微生物基因总检出率为70．9％（39／55）,其中ADV阳性率29．1％（16／55）;EBV为12．7％（7／55）;RSV为7．3％（4／55）;MP为10．9％（6／55）;CT为10．9％（6／55）。两种病毒感染阳性者为14．5％（8／55）,均为ADV感染合并其它病原体感染。对28例行常规细菌培养均为阴性。87．2％的患者经临床常规治疗获治愈。结论：分泌性中耳炎存在多种病毒、支原体、衣原体混合感染,春季是本病易发季节（4．0％）;防治感冒是预防本病的关键。     

Prevalence of Epstein-Barr virus in tonsils and adenoids of United Arab Emirates nationals

Objective

Given that Epstein-Barr virus (EBV) often inhabits human tonsils and adenoids, it remains to be distinctively determined its prevalence and in which cell and microenvironment the virus is present.

Methods

To determine the prevalence of EBV in the tonsils and adenoids of the United Arab Emirates (UAE) nationals and to provide a basis for understanding the origin and biology of EBV-infected cells, the immunophenotype of all EBV-infected cells in 46 tonsils and 46 adenoids was determined by EBER in situ hybridization and immunohistochemistry with monoclonal antibodies to T cells (CD3), B cells (CD20), and epithelial cells (cytokeratin AE1/AE3), as well as immunostaining with antibodies to EBV latent membrane protein-1 (LMP-1).

Results

EBV was found in 43% of tonsillectomy specimens and 15% of adenoidectomy specimens. All EBV-infected cells were found to be B lymphocytes. About 90% of the infected B cells are found in the interfollicular regions of tonsils and adenoids and the remaining 10% are found within the follicles. There is no significant association between EBV infection, age (P = 0.324) and gender (P = 0.442).

Conclusion

EBV is associated with tonsillar hypertrophy and is prevalent in 43% of our cases. EBV is only detected in B lymphocytes and we believe that B lymphocytes are sites of primary infection and latency. In situ hybridization is the gold standard for the detection of EBV in tissue.