Diagnostic application of Epstein-Barr virus-encoded RNA in situ hybridisation

Lymphogranuloma venereum (LGV) of the anorectum: evaluation of clinicopathological associations and the utility of a novel RNA in-situ hybridisation stain

AIMS

Recent studies from multiple global regions have reported a resurgence of lymphogranuloma venereum (LGV) proctitis, which is caused by Chlamydia trachomatis (CT). LGV proctitis is histologically indistinguishable from other forms of sexually transmitted proctitis and is difficult to differentiate from inflammatory bowel disease. While immunohistochemical stains are available for syphilis, there is no commonly available stain for the tissue identification of CT.

MATERIALS AND METHODS

From 200 positive CT nucleic acid tests (NAT) from anorectal swabs, we identified 12 patients with biopsies collected from the distal colorectum or anus within 90 days of the positive NAT. We collected basic demographic information and tabulated clinical and histological findings. We examined the performance of a novel RNA in-situ hybridisation (ISH) stain targeting CT 23s rRNA on these 12 cases and 10 controls from the anorectum.

RESULTS

All 12 patients were male; nine were HIV+, two had concurrent gonococcal infection, one had concurrent syphilis and one had cytomegalovirus co-infection. The majority of biopsies (11 of 12) showed mild or moderate acute inflammation, had a prominent lymphoplasmacytic infiltrate (eight of 11) and lacked marked crypt distortion (10 of 10). The RNA ISH stain was positive in 10 of 12 cases (sensitivity 83%). One case showed equivocal staining. No controls showed definitive positive staining (specificity 100%). One had equivocal staining.

CONCLUSION

Our series showed that anorectal LGV had similar histological findings to those of prior STI proctitis series predominantly comprised of syphilis. The novel RNA ISH stain was sensitive and specific and may show utility in differentiating types of STI proctitis.

Primary intracranial leiomyosarcoma among patients with AIDS in the era of new chemotherapeutic and biological agents

Primary intracranial leiomyosarcoma (PIL) is a rare non-infectious aetiology of focal mass lesions among HIV-infected individuals. With only 16 published cases worldwide, information on its pathophysiology, risk factors, clinical course and management options is limited. We report two cases of PIL in HIV-infected Filipino men who presented with 1-3 months history of persistent headache, progressing in severity. Both had cranial MRI revealing intracranial mass diagnosed as leiomyosarcoma by excision biopsy and immunohistochemical staining. Both patients underwent adjuvant cranial radiotherapy and chemotherapy. Biologics were initiated in one patient. Both patients were alive with evidence of the disease.

Diagnosis of Oral Hairy Leukoplakia: The Importance of EBV In Situ Hybridization

Oral hairy leukoplakia (OHL) is caused by the Epstein-Barr virus (EBV), which has been related to HIV infection. In situ hybridization (ISH) is the gold-standard diagnosis of OHL, but some authors believe in the possibility of performing the diagnosis based on clinical basis. The aim of this study is diagnose incipient lesions of OHL by EBV ISH of HIV-infected patients and the possible correlations with clinical characteristics of the patients. Ninety-four patients were examined and those presenting with clinical lesions compatible to OHL were submitted to biopsy prior to EBV ISH. Twenty-eight patients had lesions clinically compatible to the diagnosis of OHL, but only 20 lesions were confirmed by EBV ISH. The patients with OHL had a mean age of 41.9 years and were HIV-infected for 11.2 years, on average, including CD4 count of 504.7 cells/mm³ and log₁₀ viral load = 1.1. Among the quantitative variables, there was a statistically significant correlation with age only (P = 0.030). In conclusion, the presence of OHL in patients with HIV/AIDS results in changes in the epidemiological characteristics of the disease, and this fact allied with subtle clinical-morphological features makes clinical diagnosis very difficult. Therefore, EBV ISH is important for a definitive diagnosis of OHL.

Hepatoid carcinoma of the pancreas with lymphoid stroma: first description of the clinical, morphological, immunohistochemical, and molecular characteristics of an unusual pancreatic carcinoma

We report a case of tumour in the head of the pancreas observed in a 57-year-old man with a history of worsening jaundice and elevated alpha-fetoprotein (AFP) serum level, who underwent Whipple pancreatoduodenectomy. Histologically, the tumour was predominantly composed of solid sheets of large eosinophilic cells with a prominent lymphoid infiltration without association neither with DNA microsatellite instability nor Epstein-Barr virus infection. The tumour was diffusely and strongly positive for hepatocyte paraffin-1 (Hep Par-1) and glypican-3 leading to the diagnosis of hepatoid carcinoma. Strong cytoplasmic staining for AFP was focally observed. Moreover, tumour cells showed countless cytoplasmic eosinophilic globules immunoreactive for the stress protein p62. A primary hepatocellular carcinoma of the liver was ruled out by careful clinical analysis. Hepatoid carcinoma is an extremely rare pancreatic neoplasm, and here, we describe the first case of such variant associated with lymphoid stroma. The characteristic histologic features and the immunophenotypic profile help in distinguishing this carcinoma from other pancreatic tumours, notably from medullary carcinoma.

Methotrexate-associated Lymphoproliferative Disease with Multiple Pulmonary Nodules in a Patient with Rheumatoid Arthritis

Patients with rheumatoid arthritis (RA) treated with methotrexate (MTX) sometimes develop lymphoproliferative disease (LPD). MTX-associated LPD can affect nodal or extranodal sites, including the gastrointestinal tract, skin, lungs, kidneys and soft tissues, at almost equal frequency. However, it is very rare for MTX-associated LPD to manifest as multiple nodules in the lungs. We herein report the case of a RA patient who developed MTX-associated LPD with multiple pulmonary nodules during a 5-year course of MTX therapy.

Epstein-Barr virus (EBV)-encoded RNA: automated in-situ hybridization (ISH) compared with manual ISH and immunohistochemistry for detection of EBV in pediatric lymphoproliferative disorders

Detection of Epstein-Barr virus (EBV) may be achieved by various methods, including EBV-encoded RNA (EBER) in-situ hybridization (ISH) and immunohistochemistry (IHC) for latent membrane protein (LMP-1). We compared novel automated ISH and IHC techniques in pediatric lymphoproliferative disorders with results obtained by manual ISH. Thirty-seven pediatric cases previously studied by manual EBER ISH (including 18 EBER-positive, 15 EBER-negative, and 4 EBER-equivocal cases) were used for the study. Automated EBER ISH and automated LMP-1 IHC were performed using the BondMax autostainer and prediluted EBER probe and EBV cell surface 1 to 4 at 1:50 dilution, respectively. Results of each of the automated techniques for EBV detection were compared with results by manual EBER ISH. Compared with manual EBER ISH as the gold standard, automated ISH had a sensitivity and specificity of 94% and 69%, respectively, accuracy of 83%, positive predictive value (PPV) of 79%, and negative predictive value (NPV) of 90%. Automated IHC had a sensitivity of 44%, specificity of 93%, accuracy of 67%, PPV of 88%, and NPV of 59%. Automated ISH and IHC correlated significantly (P < 0.045). Automated ISH is useful for diagnosis of EBV-related pediatric neoplasms, being easy to perform and interpret and requiring only the technologist's time to set up and having a high sensitivity and NPV The automated IHC protocol is of too low sensitivity for routine use, although results show high specificity and PPV.

Atypical hyperplasia of the marginal zone of B follicles in a polymorphic Epstein-Barr virus-associated lymphoproliferative disorder occurring in an adolescent with human immunodeficiency virus infection

Epstein-Barr virus (EBV)-associated lymphoid proliferations that are similar to post-transplantation lymphoproliferative disorders may occasionally occur in the setting of human immunodeficiency virus (HIV) infection. Herein, we describe such a lesion involving the adenoids in a HIV-seropositive adolescent who acquired immunity against EBV during childhood. On microscopic examination, the marginal zone of B follicles and the interfollicular area were enlarged due to the accumulation of small or intermediate-sized lymphocytes, immunoblasts, epithelioid histiocytes, and plasma cells. A few atypical immunoblasts resembling Reed-Sternberg cells were also present. Most of the cells seen in these expanded regions belonged to the B-cell lineage and displayed a phenotype consistent with that of postgerminal center B cells. No clonal rearrangement of the genes coding for the heavy chain of the immunoglobulin could be demonstrated by polymerase chain reaction analysis. In-situ hybridization studies revealed the presence of EBV early RNA in a significant number of these cells, which suggests the participation of this virus in the pathogenesis of such a B-cell proliferation. The clinical course was benign; no progression or recurrence could be seen more than 24 months after the diagnosis. This atypical lymphoproliferative disorder is probably related to polyclonal reactivation of a latent EBV infection due to a local or systemic immune imbalance induced by HIV replication. Recognition of this reactive condition is important to prevent overtreatment.

A case of lymphomatoid granulomatosis followed for 14 months on the basis of clinical and histological findings

Lymphomatoid granulomatosis (LYG) is a systemic granulomatous disease characterized by B-cell proliferation of uncertain malignant potential. It most frequently affects the lungs but also occasionally affects the central nervous system. Its pathophysiology is unclear in numerous respects, thus making it difficult to diagnose and treat. We recently encountered a case of LYG that was followed clinically and histologically for 14 months. A 55-year-old man was hospitalized with multiple brain tumors for which the final diagnosis was not made until the second surgery, 14 months after the first intervention. Following the diagnosis, he was treated with steroid pulse therapy. At present, 3.5 years after the onset of LYG, the patient is in good condition with no signs of tumor recurrence. Although LYG is usually graded on the basis of histological findings, this patient showed no histological changes or any increase in disease grade during the 14-month follow-up period.

Persistent anemia in a patient with diffuse large B cell lymphoma: pure red cell aplasia associated with latent Epstein-Barr virus infection in bone marrow

We report a case of pure red cell aplasia (PRCA), which was initially suspected as a result of bone marrow involvement of diffuse large B cell lymphoma. Persistent anemia without an obvious cause was observed in a 47-yr-old man diagnosed with relapsed diffuse large B cell lymphoma. The bone marrow study showed only erythroid hypoplasia without the evidence of bone marrow involvement with lymphoma cells, thus PRCA was suggested. However, parvovirus infection was excluded as a potential cause of PRCA because of negative IgM anti-parvovirus B19 antibody and negative parvovirus PCR in the serum. Latent Epstein-Barr virus (EBV) infection of bone marrow was suggested by in situ hybridization with EBV-encoded small RNA (EBER) that showed a strong positive expression in bone marrow cells. Thus, PRCA was thought to be associated with latent EBV infection in bone marrow cells. Although the finding of unexplained anemia is a possible predictor of bone marrow involvement with lymphoma cells, PRCA as a result of a viral infection including EBV should be considered in lymphoma patients. This is the first report of the occurrence of PRCA associated with latent EBV infection in a patient with non-Hodgkin's lymphoma.

Epstein-Barr Virus Associated Nasopharyngeal Carcinoma and Local Polymorphic B-Cell Lymphoproliferative Disorder in a Patient With HIV Disease

A rare case report of HIV-associated nasopharyngeal carcinoma concurrent with local polymorphic B-cell lymphoproliferative disorder is reported and discussed on the ground of the most recent literature evidences. Only very few reports of nasopharyngeal carcinoma have been described until now in patients infected with HIV (one case in adults), and a coexisting lymphoid cell proliferation with a concurrent role of Epstein-Barr virus in prompting both disorders was never reported to date. The relevant pathogenetic, diagnostic, and therapeutic questions raised by this infrequent intriguing association retrieved in a patient with prominent HIV-related immunodeficiency are focused on.

Development of a quality control method for the characterization of oligonucleotides by capillary zone electrophoresis-electrospray ionization-quadrupole time of flight-mass spectrometry

A capillary zone electrophoresis-negative electrospray ionization-quadrupole time of flight-mass spectrometric method was developed for the characterization of oligonucleotides after synthesis, using model compounds. The major difficulty is the adduction of metal cations to the polyanionic backbone of the oligonucleotide sample, resulting in complex spectra and decreased sensitivity. Several approaches were investigated to circumvent this problem. Separation was performed in an ammonium carbonate buffer. During separation, the interfering metal ions were exchanged for ammonium ions, which are less tightly bound to the oligonucleotide when ionized. The influence of the addition of piperidine and imidazole or trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid (CDTA) to the running buffer for further reduction of cation adduction was investigated. Addition of CDTA to the buffer system resulted in a deconvoluted spectrum with very little adducts. On-line sample stacking proved vital to preconcentrate the samples. The pH and the concentration of the ammonium carbonate buffer as well as the electrophoresis voltage were optimized to achieve the best signal response for the oligonucleotides and a maximum reduction of the cation adducts as well as a short analysis time. Finally, the sheath liquid composition was examined for further improvement of the signal. The developed method was used to analyze different oligonucleotides (5000-9200 Da) in light of its use as a final quality control method for oligonucleotides in terms of purity and sequence homogeneity of the synthesized products. In all cases, very little adducts were observed in the deconvoluted spectra, and the relative errors of the measured molecular masses ranged from 3 to 35 ppm.