Epstein-Barr virus DNA in cerebrospinal fluid from patients with AIDS-related primary lymphoma of the central nervous system

CD8dim and NKG2D expression defines related subsets of CD4+ T cells in HIV-infected patients with worse prognostic factors

CD4 T lymphocytes expressing CD8dim (DP: CD4 CD8dim) or NKG2D represent cytotoxic effector populations, which have been involved in viral infections and chronic diseases. The frequency of DP cells was analyzed by flow cytometry in 300 consecutive HIV-infected patients and 50 healthy controls. NKG2D expression and memory/effector markers in CD4 T cells were also studied, in addition to virologic and genetic factors involved in DP T-cell expansion. HIV-infected patients showed a significantly higher frequency of DP cells than controls, mainly in patients with advanced disease. Expansion of DP cells was related to NKG2D appearance in CD4 T cells and was predicted by CD4 CD28null T-cell levels. Cells expressing CD8dim and NKG2D cells are closely related populations with a similar pattern of surface markers, perforin expression, and responses to activation. We also found that these subsets seem to share an ontogenic relationship and TcR oligoclonality. In this way, cytomegalovirus infection and certain HLA alleles, such as DR7, conditioned the expansion of DP cells. Their common ontogenic origin and oligoclonality, possibly due to repeated encounters with the same antigen, could result in a limitation of the repertoire of responder cells and in a worse prognosis of HIV infection.

Epstein-Barr Virus DNA Quantification: An Adjunctive Diagnostic Marker for AIDS-Associated Lymphoma

We report an HIV-positive patient who developed a unilateral retinitis and subsequent intracranial lesions. The finding of Epstein Barr virus (EBV) DNA at a > 1-log greater concentration in the vitreous compared to blood raised the possibility of a primary CNS non-Hodgkin's lymphoma, which was subsequently confirmed on brain biopsy. EBV DNA quantification acted as a diagnostic marker that led to a change in the management of our patient.

Unusual presentations of nervous system infection by Cryptococcus neoformans

Nervous system infections by Cryptococcus neoformans may occur not only in congenital or acquired immunodeficiency syndromes, but also in immunocompetent hosts. Neurological manifestations of C. neoformans infection include meningitis and, less commonly, parenchymal CNS granulomatous disease. This paper provides detailed clinical descriptions of highly unusual neurological manifestations of cryptococcal nervous system infections. Medical records and diagnostic data including magnetic resonance imaging, histopathology, serology, and CSF analysis were reviewed. A conus medullaris abscess was found in a patient infected with the human immunodeficiency virus (HIV). A patient with Hodgkin's disease was diagnosed with cryptococcal meningitis and dermatitis mimicking ophthalmic zoster. An immunocompetent patient presented with recurrent cerebral infarctions in the setting of cryptococcal meningitis. Cryptococcal infections of the nervous system can cause severe neurological disability when diagnosis is delayed. Sensitive and specific tests are readily available and should be considered when an unusual clinical presentation is encountered.

Detection of Epstein-Barr virus in recurrent tonsillitis

Recurrent tonsillitis has been the subject of frequent investigation. Misuse of antibiotic therapy in acute tonsillitis, changes to the tonsillar microflora, structural changes to the tonsillar crypts, and viral infections have been listed as predisposing or causal factors for recurrent tonsillitis. Epstein-Barr virus (EBV) infection usually occurs in early childhood and may persist in tonsillar lymphocytes, thus leading to the onset of recurrent tonsillitis. Little is known about the persistence and reactivation of EBV strains in immunocompetent patients. Methods such as in situ hybridization, polymerase chain reaction (PCR), and immunochemistry have been used to study the pathogenesis of the EBV. Aim: this study aims to characterize the association between EBV and recurrent tonsillitis by investigating the presence of EBV through PCR and immunohistochemistry, using viral protein LMP-1 as a target. Study design: this is a cross-sectional study with analysis of sample prevalence. Materials and method: twenty-four paraffin-embedded tonsil specimens from the Pathology Service were selected. The specimens were removed from children aged between 2 and 12 years diagnosed with recurrent tonsillitis. Results: EBV genome was detected in 13 (54.1%) specimens, whereas viral protein LMP-1 was found in 9 (37.5%) specimens. Conclusion: children’s tonsils can be colonized by EBV and such colonies may be associated with the pathogenesis of recurrent tonsillitis.

The predictive value of cerebrospinal fluid Epstein-Barr viral load as a marker of primary central nervous system lymphoma in HIV-infected persons

BACKGROUND

The presence of Epstein-Barr virus (EBV) DNA in cerebrospinal fluid (CSF) is used as a marker of HIV-associated primary central nervous system lymphoma (PCNSL). In our setting, EBV DNA is frequently detected in the CSF of HIV-infected patients with miscellaneous neurological diseases and thus its presence is a poor predictor of PCNSL.

OBJECTIVES

To determine whether quantification of EBV DNA in CSF improves its diagnostic specificity for PCNSL.

STUDY DESIGN

EBV viral loads were determined on CSF samples from 55 HIV-infected patients with CNS disease.

RESULTS

Twenty of the 55 patients had detectable EBV DNA in their CSF (median viral load 6120copies/ml, range 336-1,034,000copies/ml). PCNSL was confirmed in 2 patients. Their CSF EBV loads were 1,034,000 and 15,460copies/ml, respectively. Using a cut-off of 10,000copies/ml improved the specificity and positive predictive value (PPV) compared to a qualitative result for the diagnosis of PCNSL (96% vs. 66% and 50% vs. 10%, respectively).

CONCLUSION

EBV DNA is commonly detected in CSF of HIV-infected patients. Quantitative PCR improves the diagnostic specificity, however, the PPV remains too low for it to be used as an isolated marker for PCNSL.

The significance of Epstein-Barr virus detected in the cerebrospinal fluid of people with HIV infection

INTRODUCTION

Epstein-Barr virus (EBV) is detected in the cerebrospinal fluid (CSF) in people with HIV infection who develop primary cerebral lymphoma (PCL). However, EBV may also be detected in the CSF of patients without PCL, and here the significance is uncertain.

METHODS

Ninety-eight HIV-positive patients had lumbar punctures performed and polymerase chain reaction (PCR) for EBV was undertaken on the CSF. Thirty-eight patients had non-Hodgkin's lymphoma (NHL), including four with PCL. Sixty patients had a CSF examination for other indications. The clinicopathological details, symptoms, diagnosis, CSF and neuroimaging findings and therapy at time of CSF were recorded and correlated with CSF EBV PCR results.

RESULTS

EBV was detected in the CSF in three of four patients (75%) with PCL, one of three (33%) with systemic lymphoma and meningeal involvement, and four of 31 (13%) with systemic lymphoma and no meningeal disease. Seven of 60 patients (12%) without lymphoma were CSF EBV-positive. There were no differences in immunological, clinical, biochemical or radiological parameters between patients with and without EBV in the CSF. After a median follow-up time of 30 weeks (maximum 102 weeks), none of the seven CSF EBV-positive patients has developed PCL.

CONCLUSION

EBV was detected in up to 12% of patients with neurological symptoms but without lymphoma. A positive result did not correlate with more advanced immunosuppression or a particular neurological diagnosis. Patients with EBV in their CSF did not appear to be at increased risk of developing PCL in the short term.

Absence of Epstein-Barr Virus, Human Papillomavirus, and Simian Virus 40 in Patients of Central European Origin With Lymphoepithelioma-like Carcinoma of the Skin

The authors report 10 cases of lymphoepithelioma-like carcinoma (LELC) of the skin and the results of a molecular biological study for HPV, EBV, and SV40 in lesional tissues. All patients originated from Central Europe. There were seven men and three women, ranging in age from 57 to 86 years. Locations included the face (n = 4), scalp (n = 2), penis (n = 2), and retroauricular area (n = 1); location was unknown for one subject. All but two patients presented with a tumor confined to the skin; in both patients with the penile carcinoma, the tumors had metastasized to an inguinal lymph node. Six patients with available follow-up included four individuals with no evidence of tumor metastasis or recurrences at 2, 3, 4, and 5 years, one patient who died with metastatic disease 7 years after diagnosis, and one patient who died of an unrelated course. Microscopically, all cases showed distinctive features of LELC characterized by variably sized and shaped nodules or syncytial sheets of epithelial cells that contained vesicular chromatic and prominent nucleoli and that were permeated and surrounded by small, well-differentiated lymphocytes and plasma cells. Because all 10 cases studied proved negative for EBV, HPV, and SV40, these viruses seem to play no causal role in LELC of the skin in patients from Central Europe.

Lyme disease mimicking central nervous system lymphoma

A 33-year-old male presented with a complaint of intermittently blurred vision and right facial weakness. MRI of the brain and orbits revealed numerous cranial nerve abnormalities. There were no focal brain or spinal cord lesions. Cerebral spinal fluid flow cytometry revealed a monoclonal population of B-lymphoid cells. No other evidence of disease was found. Serum Lyme antibody was reported to be IgM positive. Therapy with ceftriaxone, was followed by improvement in his symptoms. Although flow cytometry is a useful tool in distinguishing malignancy from inflammatory disorders it does not always establish the diagnosis of malignancy by itself.

Non-Hodgkin lymphomas concurrent with HHV8-associated Kaposi's sarcoma in the same lymph node in AIDS and non-AIDS patients

BACKGROUND

The association between lymphomas and Kaposi's sarcoma has been described since 1920. The simultaneous presence of the 2 pathologic entities within the same lymph node is a rare and interesting occurrence. In the few cases described, the presence of human herpesvirus 8 (HHV8) and Epstein-Barr virus (EBV) in the different neoplastic areas was investigated only by immunohistochemistry and in situ hybridization studies.

METHODS

Two cases of concurrent non-Hodgkin lymphoma and Kaposi's sarcoma in the same lymph node are described: a diffuse large B cell lymphoma in an AIDS patient and a T cell-rich large B cell lymphoma in a HIV-negative patient, complete with the clinical, immunohistological and molecular features, the latter ones defined after isolation of the different neoplastic areas by laser capture microdissection.

RESULTS

Polymerase chain reaction assays revealed HHV8 DNA sequences only in the microdissected Kaposi's sarcoma areas and EBV DNA sequences only in the lymphomatous areas in both cases, confirming the HHV8 infection only in the neoplastic sarcomatous cells and evidencing the EBV infection only in the lymphomatous cells.

CONCLUSION

This study represents a further confirmation of the supposed different etiopathogenic mechanisms of the 2 neoplasias, suggesting a coincidental occurrence even when localized in the same lymph node, independently from HIV infection.

EBV-associated diseases in the AIDS patient

EBV-associated malignancies remain a considerable problem in HIV-infected individuals, even in the era of HAART. Although EBV is a common factor, each disease has a unique pathogenesis. Study of these diseases reveals the viral proteins expressed in the malignancies that might contribute to the development of the disease as well as the molecular basis for pathogenesis. It is likely that this knowledge will contribute to the development of novel therapeutics that will result in more favorable outcomes in the future.

Primary central nervous system lymphoma: presentation, diagnosis and staging

Primary central nervous system lymphoma (PCNSL) is a rare form of non-Hodgkin lymphoma that affects the brain, spinal cord, leptomeninges, and eyes. The clinical presentation and neuroimaging appearance of PCNSL differ in immunocompetent patients and in those with acquired immunodeficiency syndrome (AIDS). A magnetic resonance (MR) image of the brain in immunocompetent patients with PCNSL typically demonstrates one or more homogeneously enhancing lesions located in the periventricular white matter, characteristically spanning the corpus callosum. In patients with AIDS, multiple ring-enhancing lesions are more common. After neuroimages raising the suspicion of PCNSL are obtained, a definitive diagnosis should be established in both immunocompetent and AIDS patients by performing pathological analysis of cerebrospinal fluid (CSF), vitreous fluid, or a biopsy specimen. Brain biopsy sampling remains the gold standard for PCNSL diagnosis in all patients, although the possibility of establishing routine, minimally invasive diagnostic procedures in which Epstein-Barr virus polymerase chain reaction (PCR) analysis of the CSF and nuclear imaging are used is currently under investigation in the population of patients with AIDS. At the time of diagnosis, the patient should undergo further evaluation, which should include a physical examination, ophthalmic evaluation with a slit-lamp examination, serum lactate dehydrogenase levels, human immunodeficiency virus testing, computed tomography scans of the chest/abdomen/pelvis, bone marrow biopsy sampling, contrast-enhanced brain MR imaging, and lumbar puncture (LP). Testicular ultrasonography studies should be considered in men. In patients who cannot undergo LP or in those with evidence of spinal cord dysfunction, contrast-enhanced MR imaging of the entire spine should be considered.

Skewed expression of natural-killer (NK)-associated antigens on lymphoproliferations of large granular lymphocytes (LGL)

Killer-immunoglobulin-like receptors (KIR) or C-type lectin-like receptors are heterogeneously expressed on NK cells and small subsets of T cells and might provide a new diagnostic tool for LGL lymphoproliferations (LGLL). We investigated the diagnostic impact of these cell surface molecules in T- and NK-type LGLL. Using three-color flow cytometry we examined the expression patterns of KIR (CD158a/b/e/i), CD85j, lectin-like receptors (CD94, CD161, NKG2A/D) and natural cytotoxicity receptors (NKp30/44/46) in 13 patients with LGLL (10 T-, 3 NK-LGLL) and compared them to those of the corresponding lymphocyte subsets in 20 control subjects. The presence of clonal TCR-gamma rearrangements and of Epstein Barr virus- (EBV) DNA were evaluated by PCR. All patients exhibited an altered expression of NK-associated markers. KIR were either lacking (6/13) or overexpressed (7/13). CD94 expression was significantly higher in all LGLL. NKG2A expression was significantly higher in NK-LGLL. Absence or overexpression was observed for NKG2A in T-LGLL and CD161 in most T/NK-LGLL. In NK-LGLL expression of NKp30 and NKp46 was significantly decreased, whereas CD85j was overexpressed. We consistently found a skewed expression pattern of novel NK markers as a pathological feature of LGLL. These antigens should be included in the diagnostic workup of this rare disease.

Highly Active Antiretroviral Therapy and Human Immunodeficiency Virus–Associated Primary Cerebral Lymphoma

From a cohort of 9621 human immunodeficiency virus type 1-infected individuals, we identified 61 patients with primary central nervous system lymphoma (PCL) who had a median survival of 1.3 months. We compared clinicopathologic variables of patients who were treated in the pre-highly active antiretroviral therapy (HAART) and HAART eras and investigated whether exposure to antiretroviral agents with differing cerebrospinal fluid penetrations was associated with risk for PCL. All statistical tests were two-sided. Incidence of PCL was lower in the HAART era (1.2 cases per 1000 patient-years, 95% confidence interval [CI] = 0.8 to 1.9) than in the pre-HAART era (three cases per 1000 years, 95% CI = 2.1 to 4.0; P<.001), and overall survival was longer (median survival = 32 days, range = 5-315 days, versus 48 days, range = 15-1136 days; log rank P = .03). In the HAART era, fewer patients had prior acquired immunodeficiency syndrome-defining illnesses than in the pre-HAART era (64% versus 90%; P = .013), and patients were more likely to have the diagnosis of PCL confirmed histologically or by polymerase chain reaction (77% versus 26%; P<.001). Exposure to specific antiretroviral agents was not associated with risk for PCL.

Primary cutaneous histiocyte and neutrophil-rich CD30+ and CD56+ anaplastic large-cell lymphoma with prominent angioinvasion and nerve involvement in the forehead and scalp of an immunocompetent woman

BACKGROUND

Cutaneous lymphomas co-expressing CD56 and CD30 are very rare. They share a clinicopathological overlap with natural killer- (NK)/T-cell lymphomas and anaplastic large-cell lymphomas (ALCLs), two entities with widely disparate clinical behavior.

METHODS

We present a case of an immunocompetent 57-year-old Caucasian woman with a rapidly growing, angiodestructive and neuroinvasive primary cutaneous ALCL (PCALCL). The neoplastic population of large anaplastic CD30+ and CD56+ T cells was masked by a massive admixture of histiocytes and neutrophils. The partially ulcerated and pus-secreting tumor involved the forehead and scalp and was assessed as clinical stage IAE.

RESULTS

After chemotherapy (cyclophosphamide, doxorubicin, vincristine, and prednisone), the patient achieved a complete remission. Additionally, high-dose chemotherapy with autologous peripheral blood stem-cell transplantation was administered as a consolidation of complete remission, in which she has remained for 6 years.

CONCLUSIONS

This is the first CD30+ and CD56+ primary skin lymphoma to be reported on the head. The presented case carries a remarkable combination of clinicopathological features of PCALCL and NK-/T-cell lymphoma.

Results of diagnostic accuracy studies are not always validated

BACKGROUND AND OBJECTIVE

Internal validation of a diagnostic test estimates the degree of random error, using the original data of a diagnostic accuracy study. External validation requires a new study in an independent but similar population. Here we describe whether diagnostic research is validated, which technique is used, and to what extent the validation study results differ from the original.

STUDY DESIGN AND SETTING

All original diagnostic accuracy studies published in 1993 in a predefined set of journals were selected. Validation of these studies was assessed in the original article and in articles published within a period of 10 years, through a literature search and contacting the authors.

RESULTS

None of the original studies reported any form of validation. Validation studies published later could be identified for 7 of the 11 original studies. Test characteristics were difficult to compare. Despite what was generally believed, not every validation study showed results inferior to the original. We found more studies that evaluated the test in a different population than in a similar one.

CONCLUSION

Not every diagnostic accuracy study is validated. Diagnostic tests are more often repeated in different populations.

Ganciclovir is associated with low or undetectable Epstein-Barr virus DNA load in cerebrospinal fluid of patients with HIV-related primary central nervous system lymphoma

BACKGROUND

Epstein-Barr virus (EBV) is pathogenically linked to human immunodeficiency virus (HIV)-related primary central nervous system lymphoma (PCNSL) and is found in virtually all HIV-related PCNSL cases. The objective of this study was to assess the effect of ganciclovir on EBV DNA replication in patients with HIV-related PCNSL.

PATIENTS AND METHODS

EBV DNA was measured by real-time polymerase chain reaction in cerebrospinal fluid and plasma samples from 25 patients with HIV-related PCNSL. Eight of these patients were receiving ganciclovir for concurrent cytomegalovirus infections.

RESULTS

EBV DNA was detected in cerebrospinal fluid samples obtained from 15 (88%) of 17 ganciclovir-untreated patients and 4 (50%) of 8 ganciclovir-treated patients (P = .028). EBV DNA load was significantly lower for treated patients, compared with untreated patients (median value, 2.15 vs. 4.16 log copies/mL; P = .001). Analysis of sequential cerebrospinal fluid samples from 7 patients showed that EBV DNA decreased in samples obtained from 2 patients following the start of ganciclovir administration but did not decrease in samples obtained from the 5 untreated patients. In addition, patients who received ganciclovir survived longer than the untreated patients (median duration of survival, 181 vs. 72 days; P = .006).

CONCLUSION

The effect of ganciclovir on EBV DNA load in cerebrospinal fluid supports the hypothesis that EBV is replicating in patients with PCNSL. This observation, together with the effect of ganciclovir therapy on patient survival, suggests that this drug might be useful for the management of PCNSL.

Infectious pulmonary complications after stem cell transplantation or chemotherapy: diagnostic yield of bronchoalveolar lavage

Hematologic patients are at high risk for infectious pulmonary complications after stem cell transplantation (SCT) or chemotherapy. The aim of this study was to detect the range of pulmonary pathogens in these patients, analyzing 95 bronchoalveolar lavage (BAL) samples with classic and molecular (polymerase chain reaction [PCR]) detection methods. Human cytomegalovirus (HCMV) was detected in 33, herpes simplex virus in 21, human herpesvirus 6 in 24, and other viruses in 16 samples. Aspergillus species were detected in 19, Candida species in 25, and Gram-positive bacteria in 29 samples. The additional use of PCR detection methods increased the diagnostic yield from 56% to 73%, especially concerning viral and fungal infections in BAL samples. No infectious agent was detected in 26 samples. Interestingly, a high incidence of polymicrobial infections (50/95) was detected, dominated by HCMV co-infections, especially after allogeneic SCT. Within 3 years of follow-up, a poor outcome of co-infections of Aspergillus species with HCMV in 9 of 10 cases could be documented, whereas only 7 of 20 patients died with noninfectious BAL results. Herpesviruses, fungi, and Gram-positive bacteria were detected most frequently, and in 53%, polymicrobial infections were diagnosed.

AIDS-related lymphoproliferative disease

Not long after the recognition of HIV as the causative agent of AIDS, it was evident that individuals infected with HIV developed lymphoma at a greater rate than the population at large. Approximately two thirds of AIDS-related lymphoma (ARL) cases are categorized as diffuse large B-cell type, with Burkitt lymphomas comprising 25% and other histologies a much smaller proportion. Typically, these individuals have presented with advanced extranodal disease and CD4+ lymphocyte counts of less than 200/mm3. Recent clinical trials have demonstrated a better outcome with chemotherapy for ARL since the introduction of combination antiretroviral treatment, termed highly active antiretroviral therapy (HAART). For patients with relapses, solid evidence points to the safety and utility of hematopoietic-cell transplantation as a salvage modality. Coinfection with other viruses such as Epstein-Barr virus and Kaposi sarcoma-associated herpesvirus have led to the genesis of previously rare or unrecognized lymphoma subtypes such as plasmablastic and primary effusion lymphomas. The immunosuppressive impact of treatment for patients with ARL receiving chemotherapy with HAART appears transient and opportunistic infections have become less problematic than prior to HAART. Significant progress has been made in the understanding and management of ARL but outcomes still remain inferior compared to those achieved in HIV- individuals.

Changing pattern of primary cerebral lymphoma in the highly active antiretroviral therapy era

Before the introduction of highly active antiretroviral therapy (HAART), human immunodeficiency virus (HIV)-related primary central nervous system lymphoma (PCNSL) represented one of the most prevalent causes of focal brain lesions in HIV-infected people. The prognosis of PCNSL was very poor, with median survival time not exceeding 2 months. Brain biopsy was the method of choice for the definitive diagnosis, but it was and remains an invasive procedure with morbidity and mortality as well as considerable costs in terms of patients' management and quality of life. The strict association between AIDS-PCNSL and Epstein-Barr virus led to the suggestion that EBV DNA in cerebrospinal spinal fluid (CSF) might serve as a diagnostic marker, reducing the time required for diagnosis and allowing a minimally invasive approach. The clinical usefulness of this methodology has been largely demonstrated through clinical practice. After the introduction of HAART in clinical practice, a survival benefit has been observed for most persons with acquired immunodeficiency syndrome (AIDS)-associated opportunistic infections and cancers. In particular, for patients with non-Hodgkin lymphoma, a higher likelihood of response to chemotherapy as well as a longer survival has been found as a consequence of the use of combined antiretroviral therapy. Although larger studies did not show significant changes in survival of HIV-infected patients with PCNSL in the era of HAART, small case series and anecdotal reports showed the benefit of HAART in the treatment of PCNSL. Nevertheless, these patients' survival still remains very poor and it could be hypothesized that, other than specific cancer prognostic determinants and severe immunodeficiency, viral pathogenesis as well as EBV-specific immunologic dysfunction may be responsible.

LT, VP1 and TCR-BKV sequence analysis in a patient with post-transplant BKV nephropathy associated with EBV-related PTLD

A 10-year-old boy kidney transplant recipient (KTR) developed an abdominal post-transplant lymphoproliferative syndrome (PTLD) followed by BK virus nephropathy (BKVN). BK virus (BKV) and Epstein-Barr virus (EBV) were studied in renal and PTLD tissue by polymerase chain reaction (PCR) assay. Afterwards, the patient was monitored in relation to BKV in urine and serum; transcription control region (TCR)-BK polymorphism sequence analysis was also performed. In the PCR assay, both early large T antigen (LT) and late (VP1) transcriptional BKV coding regions were found in renal tissue, whereas EBV and only LT-BK were detected in PTLD abdominal tissue. On the other hand, TCR sequence analysis revealed the AS genomic BK variant.

Viral coinfection in the oral cavity of HIV-infected children: relation among HIV viral load, CD4+T lymphocyte count and detection of EBV, CMV and HSV

Viral coinfection in the oral cavity associated to HIV infection was evaluated in 180 children from birth to 13 years of age of both sexes. The oral examinations were performed at the Pediatric AIDS Outpatient Clinic, São Lucas Hospital and Clinic Hospital, both in Porto Alegre, Brazil and at the School of Dental Medicine, University Hospital Center, State University of New York at Stony Brook, USA. The aim of this study was to identify the presence of viral infections in the oral cavity. PCR technique was used to determine opportunistic viral infections caused by CMV, EBV, and HSV in mucosal swabs. A high frequency of viral infection was detected in the oral cavity of HIV-infected children determined by the PCR technique. HIV-infected children with viruses had a favorable CD4+T lymphocyte count and unfavorable viral load.

Frequent detection of Epstein-Barr Virus and cytomegalovirus but not JC virus DNA in cerebrospinal fluid samples from human immunodeficiency virus-infected patients in northern Thailand

Applying nested-PCRs, we frequently detected DNA of Epstein-Barr virus and cytomegalovirus but not JC virus in cerebrospinal fluid samples from 140 human immunodeficiency virus-infected patients with central nervous system symptoms in northern Thailand. Despite the low incidence of primary central nervous system lymphoma or cytomegalovirus encephalitis among Thai AIDS patients, Epstein-Barr virus and cytomegalovirus infections in the central nervous system are common.

Clinical Features and Diagnosis of Primary Central Nervous System Lymphoma

This article reviews the clinical features of primary central nervous system lymphoma (PCNSL) in immunocompetent and immunocompromised patients. Clinical presentation, differential diagnosis, diagnostic testing, and staging evaluation in both immunocompetent and AIDS patients who have PCNSL are discussed. The differing role of biopsy in these two populations also is addressed.

AIDS-Related Primary Central Nervous System Lymphoma

Primary central nervous system lymphoma (PCNSL) can develop in the setting of profound immunosuppression, including late-stage infection with HIV. The management of such patients has yet to be defined optimally and differs substantially from that of immunocompetent patients who have PCNSL. The clinical features, diagnosis, and management of AIDS-related PCNSL are reviewed. The authors focus on commonly encountered diagnostic and therapeutic dilemmas and explore some promises and pitfalls of Epstein-Barr virus-directed therapies.

Molecular heterogeneity of sporadic adult Burkitt-type leukemia/lymphoma as revealed by PCR and cytogenetics: correlation with morphology, immunology and clinical features

Chromosomal translocations involving the MYC oncogene are a hallmark of Burkitt lymphoma but they are only found in a varying frequency in mature Burkitt-type acute lymphoblastic leukemia (B-ALL). We have investigated samples of 56 sporadic Burkitt leukemia/lymphoma patients for the translocations t(8;14)(q24;q32), t(2;8)(p11;q24) and t(8;22)(q24;q11). Long PCR was used for detecting the immunoglobulin heavy chain (IgH) translocation and cytogenetics and/or fluorescence in situ hybridization for detecting the 'variant' MYC translocations. A total of 29 samples (51.8%) were t(8;14)-positive by long PCR. Approximately one-third had a chromosomal breakpoint in the IgH joining region while the others had breakpoints in the IgH switch regions. Among them were two cases with a previously unreported MYC translocation into the IgE switch region. Long PCR was more reliable compared to conventional cytogenetics for detecting the t(8;14). Epstein-Barr virus was detected in high copy number in two (3.6%) t(8;14)-positive cases by real-time quantitative PCR. Human herpesvirus 8 was not detected in any case by nested PCR. A typical L3 or L3-compatible cytomorphology was highly predictive (>80%) but not specific of a MYC translocation. A total of 34 patients were treated according to the GMALL B-ALL therapy protocols and there was no significant difference in overall survival between patients with or without t(8;14).

Involvement of adenovirus in clinical mononucleosis-like syndromes in young children

Although Epstein-Barr virus (EBV) commonly causes infectious mononucleosis (IM) or IM-like syndromes, other agents can be implicated. In this study, viral and parasitic screening was performed to determine the etiological agent of pediatric IM-like syndromes in 38 children. Adenovirus was the agent most frequently detected (47.3%), followed by EBV (31.5%) and cytomegalovirus (2.6%). Although the statistically significant difference between viral detection rates observed in patients who fulfilled clinical and hematological criteria and detection rates in those who presented clinical symptoms only (91.6% vs. 64.3%) indicates that hematological abnormalities are common in viral IM-like syndromes, the existence of syndromes of viral etiology without hematological criteria cannot be discarded. A further analysis showed an absence of lymphocytosis in adenovirus infections as well as a low number (14.3%) of EBV infections associated with increased neutrophils. These data suggest the usefulness of appropriate virological techniques for the detection of adenovirus in pediatric IM-like syndromes.

Detection of Coxsackievirus B3 RNA in mouse myocarditis by nested polymerase chain reaction

BACKGROUND

A majority of cases of viral myocarditis are associated with group B Coxsackieviruses (CVB) and the persistence of these viruses in the myocardium is associated with the progression of acute myocarditis to chronic dilated cardiomyopathy. A highly sensitive nested polymerase chain reaction (NPCR) is required to study the mechanisms of viral persistence in the myocardium.

OBJECTIVES

To develop an enterovirus group-specific NPCR system, to compare it to the reverse-transcription PCR (RT-PCR) plus Southern hybridisation and to investigate the dynamics of viral RNA in a murine model of myocarditis induced by CVB3.

STUDY DESIGN

Primers corresponding to the conserved sequences in the 5'-nontranslated region of enteroviruses were designed to ensure a broad specificity. The specificity of PCR products was confirmed by Southern hybridisation. The sensitivity of RT-PCR or NPCR was assessed using reconstructed infected muscle samples. The myocardial samples of the SWR murine model of CVB3-myocarditis were collected from day 1 to 30 after infection. The presence of viral RNA was detected by the RT-PCR or NPCR and infectious virus was isolated by cell culture.

RESULTS

Both RT-PCR and NPCR could detect all 11 representative enteroviruses. The NPCR could detect as few as 0.01 plaque forming unit of virus, 100 times more sensitive than the RT-PCR. Virus was isolated from the myocardium in acute phase, but was no longer recoverable after 9 days. Viral RNA was detected by the NPCR technique throughout the studied period.

CONCLUSIONS

An enterovirus group-specific NPCR system was developed and was much more sensitive than the RT-PCR technique. It can replace the Southern hybridisation of RT-PCR products. The presence of viral RNA in the myocardium after acute phase indicates a possibility of CVB3 shifting to persistent infection in the SWR mice.

Molecular methods for diagnosis of viral encephalitis

Hundreds of viruses cause central nervous system (CNS) disease, including meningoencephalitis and postinfectious encephalomyelitis, in humans. The cerebrospinal fluid (CSF) is abnormal in >90% of cases; however, routine CSF studies only rarely lead to identification of a specific etiologic agent. Diagnosis of viral infections of the CNS has been revolutionized by the advent of new molecular diagnostic technologies to amplify viral nucleic acid from CSF, including PCR, nucleic acid sequence-based amplification, and branched-DNA assay. PCR is ideally suited for identifying fastidious organisms that may be difficult or impossible to culture and has been widely applied for detection of both DNA and RNA viruses in CSF. The technique can be performed rapidly and inexpensively and has become an integral component of diagnostic medical practice in the United States and other developed countries. In addition to its use for identification of etiologic agents of CNS disease in the clinical setting, PCR has also been used to quantitate viral load and monitor duration and adequacy of antiviral drug therapy. PCR has also been applied in the research setting to help discriminate active versus postinfectious immune-mediate disease, identify determinants of drug resistance, and investigate the etiology of neurologic disease of uncertain cause. This review discusses general principles of PCR and reverse transcription-PCR, including qualitative, quantitative, and multiplex techniques, with comment on issues of sensitivity, specificity, and positive and negative predictive values. The application of molecular diagnostic methods for diagnosis of specific infectious entities is reviewed in detail, including viruses for which PCR is of proven efficacy and is widely available, viruses for which PCR is less widely available or for which PCR has unproven sensitivity and specificity, and nonviral entities which can mimic viral CNS disease.

Factors influencing PCR detection of viruses in cerebrospinal fluid of patients with suspected CNS infections

BACKGROUND

Polymerase chain reaction (PCR) is used to detect viruses in the cerebrospinal fluid (CSF) of patients with neurological disease. However, data to assist its use or interpretation are limited.

OBJECTIVE

We investigated factors possibly influencing viral detection in CSF by PCR, which will also help clinicians interpret positive and negative results.

METHODS

CSF from patients with was tested for human herpesviruses types 1-6, JC virus, enteroviruses, and Toxoplasma gondii. The likelihood of central nervous system (CNS) infection was classified as likely, possible, or unlikely. PCR findings in these categories were compared using single variable and logistic regression analysis.

RESULTS

Of 787 samples tested, 97 (12%) were PCR positive for one or more viruses. Of episodes likely to be CNS viral infections, 30% were PCR positive compared to 5% categorised as unlikely. The most frequent positive findings were Epstein Barr virus (EBV), enteroviruses, and herpes simplex virus (HSV). Enteroviruses and HSV were found predominantly in the likely CNS viral infection group, whereas EBV was found mainly in the unlikely group. Positive PCR results were more likely when there were 3-14 days between symptom onset and lumbar puncture, and when CSF white cell count was abnormal, although a normal CSF did not exclude a viral infection.

CONCLUSIONS

The diagnostic yield of PCR can be maximised by using sensitive assays to detect a range of pathogens in appropriately timed CSF samples. PCR results, in particular EBV, should be interpreted cautiously when symptoms cannot readily be attributed to the virus detected.

AIDS-related cancer in the era of highly active antiretroviral therapy (HAART): a model of the interplay of the immune system, virus, and cancer. "On the offensive--the Trojan Horse is being destroyed"--Part B: Malignant lymphoma

The impact of highly active antiretroviral therapy (HAART) on the incidence of non-Hodgkin's lymphoma was less obvious initially, although primary central nervous system lymphoma (PCNSL) has dropped precipitously since the introduction of HAART. The pathogenesis of acquired immunodeficiency syndrome-related lymphoma is multifactorial. Epstein-Barr virus plays a significant role in these diseases, especially Burkitt lymphoma and PCNSL. Data regarding the effect of HAART on the natural history and treatment outcomes of these malignancies are emerging. The possibility of direct and indirect roles of human immunodeficiency virus in the carcinogenesis suggests that antiretroviral therapy may be an important component of the treatment for these malignancies. The simultaneous administration of HAART and chemotherapy does not appear to significantly alter the toxicity profile, although the information with respect to the interaction of HAART and chemotherapy is limited. The use of biological agents, for example, monoclonal antibody against CD-20, is being explored to improve the clinical outcome of this disease.

Human herpes virus 6 or Epstein-Barr virus were not detected in Guthrie cards from children who later developed leukaemia

To investigate if children who later developed acute lymphoblastic leukaemia (ALL) were prenatally infected with HHV-6 and/or EBV, Guthrie cards taken at birth were analysed by PCR. Guthrie cards from 54 patients with ALL and 47 healthy controls matched for age and birth place were tested negative for both HHV-6 and EBV DNA. All samples contained amplifiable DNA when tested by HLA-DQ PCR. Our negative findings suggest that childhood ALL is unlikely to be associated with an in utero infection with EBV or HHV-6.

The epidemiology of non-Hodgkin's lymphoma

The incidence of non-Hodgkin's lymphoma (NHL) has doubled over the past two decades in the US and most other westernized countries. While improved cancer reporting, changes in lymphoma classification, and increases in AIDS-associated lymphomas have contributed to the startling escalation of disease incidence, these factors are estimated to account for only about 50% of the increase in observed incidence. The elucidation of etiologic factors and their mechanistic role in the pathogenesis of this malignancy are critical to advancements in disease prevention and treatment. Current evidence suggests that factors/conditions that precipitate either chronic antigenic stimulation or immunosuppression may provide a preferential milieu for development of NHL. High rates of lymphoma have been observed among individuals with autoimmune disease, organ transplants, and primary or acquired immunodeficiencies. Ultraviolet radiation, previously demonstrated to have an immunosuppressive effect, has also been suggested as a possible risk factor for NHL. Several pathogens have been linked to the risk of lymphoma, including Epstein-Barr virus, human immunodeficiency virus, human T-cell lymphotropic virus-1, Helicobacter pylori, hepatitis C, and simian virus 40. Whether these microbes are responsible for specific genetic mutations that initiate tumor growth, antigenic stimulation leading to B-cell proliferation, and increased potential of random cell replication errors, or immunosuppression, which thereby promotes tumor growth, has not been clearly delineated. Other exogenous factors which have been implicated in lymphomagenesis are chemicals and agricultural exposures, hair dyes, and blood transfusions. We must build on our current knowledge regarding the etiology of NHL in order that prevention, treatment, and ultimately, cure of this malignancy becomes a reality.

Guidelines for the diagnosis and management of neurological complications of HIV infection

The spectrum of neurological complications of HIV-infection has remained unchanged through the years, but its epidemiology changed remarkably as a result of the introduction of highly active antiretroviral therapy (HAART). Guidelines for the diagnosis and treatment of cerebral toxoplasmosis, cryptococcal meningitis, progressive multifocal leukoencephalopathy, CMV encephalitis, CMV polyradiculomyelitis, tuberculous meningitis, primary CNS lymphoma, HIV dementia, HIV myelopathy and HIV polyneuropathy are given with a grading of evidence and recommendations.

Varicella-zoster viral meningitis mimicking lymphoma

We report the case of a 30-year-old HIV-infected man admitted for a meningeal syndrome and a zoster rash. The CSF had cytological features suggesting a primary CNS lymphoma (PCNSL). The large lymphoid cells had a fine chromatin with nucleoli, a basophilic cytoplasm with azurophilic granules and high mitotic activity. Several arguments demonstrated the viral origin of the meningitis: the large lymphoid cells were of T origin with no evidence of clonal TCR gamma gene rearrangement. The PCR was positive for Varicella-Zoster Virus (VZV) and EBV DNA. Clinical evolution was favorable under acyclovir. We should be cautious in the differential diagnosis between viral meningitis and PCNSL.

Predictive Value of Polymerase Chain Reaction of Cerebrospinal Fluid for Detection of Epstein-Barr Virus to Establish the Diagnosis of HIV-Related Primary Central Nervous System Lymphoma

Polymerase chain reaction (PCR) of cerebrospinal fluid (CSF) for detection of Epstein-Barr virus (EBV) DNA has been proposed as a minimally invasive method for establishing the diagnosis of human immunodeficiency virus-related primary central nervous system lymphoma (PCNSL). In a review of the operational characteristics of this test in our clinical practice, the positive predictive value of CSF PCR for EBV for establishing the diagnosis of PCNSL was only 29%. Of 7 patients with CSF PCR positive for EBV, 2 had PCNSL, and 5 received alternative diagnoses (specificity, 79.1%).

B cell clonality in multiple localizations of primary central nervous system lymphomas in AIDS patients

The aim of our study was to investigate B cell clonality of distinct localizations of primary central nervous system lymphomas (PCNSL) in AIDS patients. We selected seven autoptic cases of AIDS PCNSL with at least two separated localizations of the disease in the central nervous system (CNS). Clonality was investigated by immunoglobulin light chain restriction and by semi-nested PCR for the immunoglobulin heavy chain (IgH). Three cases showed a concordant restriction in the two lesions. In an additional case, an identical IgH sequence was found. The remaining three cases did not provide consistent information because of extensive necrosis in the lesions. Our findings suggest that multifocality of PCNSL is due to dissemination of a single neoplastic clone rather than to a synchronous transformation of multiple B cell clones.

Detection of TT virus in lymph node biopsies of B-cell lymphoma and Hodgkin's disease, and its association with EBV infection

Human TT virus (TTV) recently isolated from the serum of a patient with post-transfusion hepatitis does seem to have only hepatopathic effect. The virus can also infect the serum, peripheral blood mononuclear cells (PBMC) and bone marrow cells (BMC ). Additional evidence has indicated that TTV is also present in the serum of people with hematopoietic malignancies. A significant increase in the incidence of lymphoma has recently been observed worldwide. We have investigated the presence of TTV DNA in lymph node biopsies of Italian patients affected with the most common lymphoma types in Western Countries: follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL) and nodular sclerosis Hodgkin's disease (NS-HD). The possible role of a co-infection with Epstein-Barr virus (EBV) has also been investigated. DNA was extracted from 73 paraffin-embedded and 38 snap-frozen tissue specimens. From these, only 67 samples (29 paraffin-embedded and 38 snap-frozen tissues) from a total of 56 patients, were suitable for PCR analysis. TTV and EBV were detected by PCR using primers from two different conserved region in TTV and EBV genomes respectively. TTV DNA was detected in 30.0-50.0% of FL, 30.8% of DLBCL and 30.0-50.0% of NS-HD cases, depending on the primers used. All cases of non-specific reactive lymphoid hyperplasia (RLH), used as a putative control, were negative. The two major TTV genotypes circulating in Italy (G1 and G2) were detected in the analysed lymphoid neoplasms. EBV DNA was detected in 40.0% of FL, in 72.7%of DLBCL, in 80.0% of SN-HD and in 40.0% of RLH cases. EBV co-infection was found in 90% of TTV positive cases. The in situ hybridization assay was performed in TTV positive frozen samples. The significant prevalence of TTV DNA in lymphocytes circulating in the lymph nodes of both B-cell lymphomas and HD reported herewith suggests an implication of TTV infection in the development of these lymphoproliferative disorders.

Update on the Pathogenesis, Diagnosis, and Therapy of AIDS-related Lymphoma

AIDS-related non-Hodgkin's lymphoma (ARL) is an opportunistic malignancy that foreshortens life more than any other commonly occurring HIV-associated cancer. Treatment strategies include low-dose chemotherapy, chemotherapy given with antiretroviral therapy, and infusional chemotherapy regimens. Rituximab, an anti-CD20 monoclonal antibody, has been found to be useful in non-HIV-associated lymphomas and is of interest in ARL as well. Since the advent of highly active antiretroviral therapy, the ARL incidence and survival has changed. This paper reviews the epidemiologic, biologic, and clinical features of ARL with the aim of presenting a cohesive overview of these elements.