RESUMO
BACKGROUND COVID-19 was declared a pandemic in March 2020 in the United States. It has been associated with high mortality and morbidity all over the world. COVID-19 can cause a significant inflammatory response leading to coagulopathy and this hypercoagulable state has been associated with worse clinical outcomes in these patients. The published data regarding the presence of lupus anticoagulant in critically ill COVID-19-positive patients is limited and indicates varying conclusions so far. CASE REPORT Here, we present a case of a 31-year-old man who was admitted to the hospital with COVID-19 pneumonia, complicated with superadded bacterial empyema and required video-assisted thoracoscopic surgery with decortication. This patient also had prolonged prothrombin time on preoperative labs, which was not corrected with mixing study. Further workup detected positive lupus anticoagulant and anti-cardiolipin IgM along with alteration in other coagulation factor levels. The patient was treated with fresh frozen plasma and vitamin K before surgical intervention. He had an uneventful surgical course. He received prophylactic-dose low molecular weight heparin for venous thromboembolism prophylaxis and did not experience any thrombotic events while hospitalized. CONCLUSIONS COVID-19 infection creates a prothrombotic state in affected patients. The formation of micro-thrombotic emboli results in significantly increased mortality and morbidity. Routine anticoagulation with low molecular weight heparin can prevent thrombotic events and thus can improve patient outcomes. In patients with elevated prothrombin time, lupus anticoagulant/anti-cardiolipin antibody-positivity should be suspected, and anticoagulation prophylaxis should be continued perioperatively for better outcomes.
Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Empiema Pleural/virologia , Inibidor de Coagulação do Lúpus/sangue , Pneumonia Viral/complicações , Adulto , Antifibrinolíticos/uso terapêutico , COVID-19 , Cardiolipinas/imunologia , Tubos Torácicos , Infecções por Coronavirus/diagnóstico , Empiema Pleural/diagnóstico por imagem , Empiema Pleural/terapia , Humanos , Imunoglobulina M/sangue , Coeficiente Internacional Normatizado , Masculino , Pandemias , Tempo de Tromboplastina Parcial , Plasma , Pneumonia Viral/diagnóstico , Tempo de Protrombina , SARS-CoV-2 , Tomografia Computadorizada por Raios X , Tromboembolia Venosa/prevenção & controle , Vitamina K/uso terapêuticoRESUMO
Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphomas associated with chronic inflammation (DLBCL-CI) develop in patients with chronic inflammation but without any predisposing immunodeficiency. Given the expression of the EBV latent genes, DLBCL-CI should have mechanisms for evasion of host antitumor immunity. EBV-positive pyothorax-associated lymphoma (PAL) is a prototype of DLBCL-CI and may provide a valuable model for the study of immune evasion by DLBCL-CI. This study demonstrates that PAL cell lines express and secrete CCL17 and/or CCL22 chemokines, the ligands of C-C motif chemokine receptor 4 (CCR4), in contrast to EBV-negative DLBCL cell lines. Accordingly, culture supernatants of PAL cell lines efficiently attracted CCR4-positive regulatory T (Treg) cells in human peripheral blood mononuclear cells. PAL cells injected into mice also attracted CCR4-expressing Treg cells. Furthermore, this study confirmed that CCR4-expressing Treg cells were abundantly present in primary PAL tissues. Collectively, these findings provide new insight into the mechanisms of immune evasion by PAL, and further studies are warranted on whether such mechanisms eventually lead to the development of DLBCL-CI.
Assuntos
Quimiocina CCL17/biossíntese , Quimiocina CCL22/biossíntese , Empiema Pleural/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Linfoma Difuso de Grandes Células B/imunologia , Linfócitos T Reguladores/imunologia , Animais , Linhagem Celular Tumoral , Quimiocina CCL17/imunologia , Quimiocina CCL22/imunologia , Empiema Pleural/patologia , Empiema Pleural/virologia , Infecções por Vírus Epstein-Barr/patologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Inflamação/virologia , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/virologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Receptores CCR4/biossíntese , Receptores CCR4/imunologiaRESUMO
Pyothorax-associated lymphoma (PAL) develops from a pyothorax caused by an artificial pneumothorax created during the treatment of pulmonary tuberculosis or tuberculous pleuritis. We report the first case of Epstein-Barr virus (EBV)-positive PAL arising from a posttraumatic empyema. A 75-year-old woman with chronic posttraumatic empyema presented with a tumor, which was connected to the wall of a pyothorax in the right thoracic cavity. She had a history of trauma to the right chest, which had occurred at the age of 45 years and had caused the chronic posttraumatic empyema. Pathological features of the resected tumor were conclusive for a diagnosis of EBV-positive PAL. Although neither postoperative chemotherapy nor radiotherapy was performed, remission was maintained for 3 years until recurrence in the liver. Combination chemotherapy led to complete remission, and 9 years after the initial diagnosis of PAL, the patient is still alive. An intriguing finding is the phenotypic alteration during the disease course. Although the primary tumor was negative for CD20 and CD3, the recurrent tumor expressed both of these molecules. We discuss this case of PAL, which was not a complication of lung tuberculosis, and the aberrant chronological phenotypic change observed in the lymphoma cells, and compare it with a usual case of PAL.
Assuntos
Empiema Pleural/complicações , Herpesvirus Humano 4/isolamento & purificação , Linfoma/diagnóstico , Traumatismos Torácicos/complicações , Idoso , Empiema Pleural/virologia , Feminino , Humanos , Linfoma/etiologia , Linfoma/patologia , Linfoma/virologia , RecidivaRESUMO
Pyothorax-associated lymphoma (PAL) is a B-cell non-Hodgkin's lymphoma, and develops after 20-40 years of pyothorax or pleuritis including tuberculosis. An 88-year-old Japanese woman developed fever and right pleural effusion. No mycobacterium was recognized by Ziel-Neelsen stain, culture tests and PCR technique in the effusion. The patient was diagnosed as non-specific pleuritis. No tumor formations were seen in the right pleura by imaging modalities, and she was treated by antibiotics. Eight months later, she complained of severe back pain and fever. Imaging modalities revealed many tumors in the right pleura, and biopsy of the tumors was performed. The biopsy showed severe diffuse proliferation of lymphoid cells. The lymphoid cells consisted of atypical large lymphoid cells and small lymphoid cells. The large atypical cells were positive for CD45 and CD20 but negative for CD15 and CD30, thus confirming B cell neoplasm. Ki-67 labeling was 79%. The small cells were positive for CD45, CD20 and CD3, reflecting a mixture of mature B and T-cells. The small cells appeared non-neoplastic inflammatory cells. CD68-positive macrophages were also scattered. In situ hybridization for EB virus DNA showed positive signals in the large atypical B-cells and, to a lesser degree, in the small lymphocytes. The author thinks that this tumor is PAL with inflammatory reaction. The present case shows that the duration between PAL and pleuritis can be very short, and PAL may be associated with inflammatory reaction at the early neoplastic stage.
Assuntos
Empiema Pleural/patologia , Linfoma de Células B/patologia , Doença Aguda , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , DNA Viral/análise , Empiema Pleural/metabolismo , Empiema Pleural/virologia , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/patologia , Feminino , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Humanos , Hibridização In Situ , Linfoma de Células B/metabolismo , Linfoma de Células B/virologia , Derrame Pleural/metabolismo , Derrame Pleural/patologia , Derrame Pleural/virologiaRESUMO
Pandemic influenza A H1N1 virus is likely to cause severe disease in patients who have received solid organs transplants. In these patients pneumonia is the most frequent clinical feature. Parapneumonic empyema (PPE) may represent the evolution of secondary bacterial respiratory infections. To our knowledge this is the first reported case of PPE during H1N1 influenza A in an adult heart transplanted patient. The patient was treated successfully with surgical empyemectomy and lung decortication, broad-spectrum antibiotics and oseltamivir. Eradication of influenza was obtained in the fifth postoperative day.
Assuntos
Antibacterianos/uso terapêutico , Antivirais/uso terapêutico , Empiema Pleural/terapia , Transplante de Coração/efeitos adversos , Vírus da Influenza A Subtipo H1N1/patogenicidade , Oseltamivir/uso terapêutico , Pneumonia Viral/terapia , Procedimentos Cirúrgicos Pulmonares , Adulto , Cardiomiopatia Dilatada/cirurgia , Terapia Combinada , Empiema Pleural/diagnóstico , Empiema Pleural/virologia , Humanos , Imunossupressores/efeitos adversos , Masculino , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do TratamentoAssuntos
Empiema Pleural , Infecções por Haemophilus/complicações , Vacinas Anti-Haemophilus/uso terapêutico , Haemophilus influenzae tipo b/isolamento & purificação , Técnicas de Tipagem Bacteriana , Empiema Pleural/diagnóstico por imagem , Empiema Pleural/terapia , Empiema Pleural/virologia , Humanos , Lactente , Masculino , Radiografia Torácica , SorotipagemAssuntos
Empiema Pleural/patologia , Infecções por Vírus Epstein-Barr , Linfoma Difuso de Grandes Células B/patologia , Neoplasias Pleurais/patologia , Adulto , Antígenos CD20/metabolismo , Empiema Pleural/complicações , Empiema Pleural/diagnóstico por imagem , Empiema Pleural/virologia , Humanos , Antígeno Ki-67/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/cirurgia , Linfoma Difuso de Grandes Células B/virologia , Masculino , Neoplasias Pleurais/complicações , Neoplasias Pleurais/metabolismo , Neoplasias Pleurais/cirurgia , Neoplasias Pleurais/virologia , RadiografiaRESUMO
We report a case of rapid progression of bilateral pyothorax exacerbated by viral influenza in an infant. The patient, an 11-month-old girl, was diagnosed with viral influenza, and oseltamivir phosphate was administered. However, after only 4 days the influenza was followed by rapid progression of methicillin-susceptible Staphylococcus aureus (MSSA) pneumonia and pyothorax, resulting in disseminated intravascular coagulation. Because thoracentesis and antibiotics could not control the pyothorax, a serious condition, we performed bilateral video-assisted thoracoscopic decortication on the eighth hospital day. She recovered with excellent lung expansion and was discharged on the 37th hospital day.
Assuntos
Empiema Pleural/microbiologia , Empiema Pleural/cirurgia , Pneumonia Estafilocócica/diagnóstico , Cirurgia Torácica Vídeoassistida , Antibacterianos/uso terapêutico , Coagulação Intravascular Disseminada/microbiologia , Drenagem , Empiema Pleural/virologia , Feminino , Humanos , Lactente , Vírus da Influenza A , Influenza Humana/complicações , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Pneumonia Estafilocócica/tratamento farmacológico , Resultado do TratamentoAssuntos
Empiema Pleural/complicações , Linfoma de Células B/patologia , Linfoma Difuso de Grandes Células B/patologia , Neoplasias Torácicas/patologia , Idoso de 80 Anos ou mais , Doença Crônica , Empiema Pleural/virologia , Infecções por Vírus Epstein-Barr , Evolução Fatal , Humanos , Linfoma de Células B/diagnóstico , Linfoma de Células B/etiologia , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/etiologia , Masculino , Neoplasias Torácicas/diagnóstico , Neoplasias Torácicas/etiologiaAssuntos
Empiema Pleural/diagnóstico por imagem , Empiema Pleural/virologia , Infecções por Vírus Epstein-Barr/complicações , Linfoma de Células B/virologia , Idoso , Empiema Pleural/complicações , Humanos , Linfoma de Células B/complicações , Masculino , Radiografia Torácica , Tomografia Computadorizada por Raios XRESUMO
Malignant lymphoma frequently develops in the pleural cavity of patients with over 20 years' history of pyothorax. The term pyothorax-associated lymphoma (PAL) has been proposed for this type of tumor. We established four novel lymphoma cell lines (OPL-3, -4, -5, and -7) from four patients with PAL. Characteristics of the four cell lines are as follows: B-cell nature with defective expression of B-cell and T-cell surface antigens, monoclonal pattern of Epstein-Barr virus (EBV) infection in lymphoma cells (thus indicating an etiological role of EBV for lymphomagenesis), complicated chromosomal abnormalities with numerous structural and numerical abnormalities, and occasional but distinct genome instability. These abnormalities in cell character might be caused by the specific circumstances of PAL lymphomagenesis, i.e., chronic inflammation. Thus, PAL cell lines could be useful in analysis of molecular mechanisms leading to malignancy in chronic inflammation.
Assuntos
Técnicas de Cultura de Células/métodos , Empiema Pleural/patologia , Empiema Pleural/virologia , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/virologia , Linfoma/patologia , Linfoma/virologia , Idoso , Idoso de 80 Anos ou mais , Biópsia , Southern Blotting , Linhagem Celular Tumoral , Empiema Pleural/metabolismo , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Feminino , Citometria de Fluxo , Rearranjo Gênico/genética , Genes Codificadores dos Receptores de Linfócitos T/genética , Herpesvirus Humano 4/fisiologia , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Linfoma/complicações , Linfoma/genética , Masculino , Repetições de Microssatélites/genética , FenótipoRESUMO
We treated a 73-year-old man who developed a pyothorax-associated pleural lymphoma after a 52-year history of tuberculous pleuritis. The lymphoma was classified histologically as a diffuse large, B-cell type. Epstein-Barr virus (EBV) was identified in the tumor by immunocytochemical and molecular methods. Chemotherapy both without and with the addition of rituximab was only minimally effective, but adding radiotherapy to chemotherapy reduced the tumor size, resulting in a partial remission. The EBV load measured by a quantitative real-time polymerase chain reaction correlated well with the tumor size and the serum lactate dehydrogenase concentration. Monitoring the EBV load may be useful in the management of pyothorax-associated lymphoma.
Assuntos
Empiema Pleural/virologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/fisiologia , Linfoma/virologia , Carga Viral , Empiema Pleural/complicações , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/efeitos dos fármacos , Humanos , Linfoma/complicações , MasculinoAssuntos
Empiema Pleural/complicações , Infecções por Vírus Epstein-Barr/complicações , Linfoma Difuso de Grandes Células B/etiologia , Anticorpos Antivirais/sangue , Empiema Pleural/patologia , Empiema Pleural/virologia , Infecções por Vírus Epstein-Barr/diagnóstico , Infecções por Vírus Epstein-Barr/patologia , Antígenos Nucleares do Vírus Epstein-Barr/análise , Humanos , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/virologia , Masculino , Pessoa de Meia-Idade , Pneumotórax Artificial , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/cirurgia , Tuberculose Pulmonar/virologia , Proteínas ViraisAssuntos
Empiema Pleural/virologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/patogenicidade , Linfoma de Células T Periférico/virologia , Neoplasias Pleurais/virologia , Idoso , Anticorpos Antivirais/análise , DNA Viral/análise , Suscetibilidade a Doenças , Antígenos Nucleares do Vírus Epstein-Barr/imunologia , Feminino , Herpesvirus Humano 4/isolamento & purificação , Humanos , Imunofenotipagem , Japão , Linfoma de Células T Periférico/etnologia , Linfoma de Células T Periférico/etiologia , Neoplasias Pleurais/etnologia , Neoplasias Pleurais/etiologia , Pneumotórax Artificial/efeitos adversos , Tuberculose Pulmonar/terapiaRESUMO
B cell lymphoma develops in the pleural cavity of patients affected by long-standing pyothorax resulting from lung tuberculosis, thus termed pyothorax-associated lymphoma (PAL). PAL usually shows a diffuse large cell morphology, and constantly contains Epstein-Barr virus (EBV) genome. To investigate whether PAL cells proliferate in response to specific antigenic stimuli and its stage in B cell differentiation, immunoglobulin heavy chain gene in 7 cases and 2 cell lines from PAL, all confirmed by histological studies to be EBV-positive diffuse large B cell lymphoma, were examined by using polymerase chain reaction (PCR) method. Clonal rearrangement of the gene was detected in 4 cases of PAL tissues and one cell line. As for the usage of the V region gene (V(H)), the V(H)3 family gene was used in 3 of these 5 cases with different homologous germlines, suggesting that the origin of PAL cells from a repertoire of B lymphocytes responsive to specific antigenic epitope was unlikely. Compared to the homologous germline, the mutation frequency of PAL was 9% on average. Only one case might have more replacement mutations in the complementarity-determining regions than expected by chance, thus antigen-selected maturation might not take place in PAL. Intraclonal sequence heterogeneity in the V(H) gene was found in another case. From these findings, it is concluded that PAL is composed of B lymphocytes at the differentiation stage of the postgerminal center. Antigen-selected maturation might not take place in PAL, which is distinct from the majority of B cell lymphomas.
Assuntos
DNA de Neoplasias/análise , Empiema Pleural/genética , Genes de Imunoglobulinas , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Linfoma de Células B/genética , Neoplasias Pleurais/genética , Idoso , Linfócitos B/imunologia , Sequência de Bases , Primers do DNA/química , Empiema Pleural/imunologia , Empiema Pleural/virologia , Infecções por Vírus Epstein-Barr/virologia , Feminino , Humanos , Linfoma de Células B/imunologia , Linfoma de Células B/virologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Neoplasias Pleurais/imunologia , Neoplasias Pleurais/virologia , Pneumotórax Artificial/efeitos adversos , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Homologia de Sequência do Ácido NucleicoRESUMO
We report 12 European cases of pyothorax-associated lymphomas occurring 30-67 years following artificial pneumothorax for pleuropulmonar tuberculosis. Eleven patients presented with a localized pleural tumor mass, whereas one patient also had liver involvement. Histologic examination showed a diffuse proliferation of large lymphoid cells with frequent plasmacytoid differentiation (n = 8), expressing CD20 (n = 10), CD79a (n = 11), and/or CD138 (n = 5) B-cell antigens. Aberrant expression of T-cell markers (CD2, CD3, CD4) was noted in five cases. The B-cell origin of lymphoma cells was confirmed by the demonstration of immunoglobulin light chain restriction or clonal B cell population in six cases. In 11 of 12 cases in situ hybridization disclosed Epstein-Barr virus genome in most tumor cells and immunohistochemistry a type III LMP-1+/ EBNA-2+ latency profile. HHV-8/ORF73 antigen was not detected in all tested cases (n = 11). All investigated cases (10 of 10) disclosed a uniform CD10-/BCL-6-/MUM1+/CD138+/- phenotype, consistent with a derivation from late germinal center (GC)/post-GC B cells. Clinical outcome was poor with a median survival time of 5 months. Only one patient was in complete remission after 34 months. This study further confirms that pyothorax-associated lymphoma represents a distinct clinicopathologic entity among diffuse large B-cell lymphoma, which is characterized by a peculiar clinical presentation, frequent plasmacytoid features, and a strong association with EBV. Moreover, we show that this lymphoma entity likely originates from B cells at a late stage of differentiation and occasionally shares an aberrant dual B/T phenotype.
Assuntos
Linfócitos B/patologia , Empiema Pleural/complicações , Linfoma de Células B/complicações , Neoplasias Pleurais/complicações , Linfócitos T/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Biópsia , Diferenciação Celular , Empiema Pleural/patologia , Empiema Pleural/virologia , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/patologia , Feminino , Centro Germinativo/patologia , Centro Germinativo/virologia , Herpesvirus Humano 4/isolamento & purificação , Herpesvirus Humano 4/fisiologia , Humanos , Técnicas Imunoenzimáticas , Hibridização In Situ , Linfoma de Células B/patologia , Linfoma de Células B/virologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Neoplasias Pleurais/patologia , Neoplasias Pleurais/virologia , Pneumotórax Artificial/efeitos adversosRESUMO
Pyothorax-associated lymphoma (PAL) is a clinico-pathological entity arising in the pleural cavity of patients with long-standing inflammatory pyothorax. PAL is closely associated with Epstein-Barr virus (EBV), but how this virus contributes to the development of the lymphoma is unknown. We have successfully obtained a novel EBV-infected PAL cell line, designated Pal-1. The cell line and its source coexpressed CD2 and CD20 molecules, but other representative B- and T-cell markers such as CD1, CD3, CD5, CD7, CD10 and CD19 were not found. The B-cell origin of Pal-1 cells was proven by rearrangement of the immunoglobulin heavy- and light-chain genes without rearranged T-cell receptor genes. Both the cell line and primary tumour cells carried monoclonal EBV genome. Although EBV genome is known to be maintained as circular extrachromosomal DNA, neither circular nor linear extrachromosomal EBV DNA was detectable in Pal-1 cells by in situ lysis gel analysis. Fluorescence in situ hybridization demonstrated viral integration at a marker chromosome mostly consisting of the centromere region of chromosome 1. The viral integration event may enhance a chromosomal instability at the insertion site. This cell line represents the first example of EBV integration in PAL and could enable the study of the potential role of integrated viral infection in the development of PAL as well as mechanism of the aberrant phenotype expression.
Assuntos
Empiema Pleural/virologia , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/genética , Linfoma de Células B/virologia , Integração Viral , Idoso , Southern Blotting , Antígenos CD2/análise , Expressão Gênica , Rearranjo Gênico do Linfócito B , Genoma Viral , Genótipo , Humanos , Cariotipagem , Masculino , Fenótipo , Células Tumorais CultivadasAssuntos
Empiema Pleural/complicações , Empiema Pleural/virologia , Herpesvirus Humano 4/fisiologia , Linfoma/complicações , Linfoma/virologia , Citocinas/imunologia , Empiema Pleural/imunologia , Empiema Pleural/patologia , Antígenos Nucleares do Vírus Epstein-Barr/genética , Antígenos Nucleares do Vírus Epstein-Barr/imunologia , Genes p53/genética , Antígenos HLA/genética , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 8/fisiologia , Doença de Hodgkin/imunologia , Doença de Hodgkin/patologia , Doença de Hodgkin/virologia , Humanos , Linfoma/imunologia , Linfoma/patologia , Linfócitos T Citotóxicos/imunologiaRESUMO
AIMS: Pyothorax associated lymphoma (PAL) occurs in a clinical setting of longstanding pyothorax or chronic inflammation of the pleura. Like primary effusion lymphoma, it has an association with Epstein-Barr virus (EBV), and is confined to the pleural cavity, but has differing morphological and phenotypic features. Human herpesvirus 8 (HHV-8) has been consistently reported in primary effusion lymphoma. This study examines the immunophenotype of two European cases of PAL, investigates the presence of HHV-8 and its expression profile, and assesses whether PAL is similar to other effusion lymphomas. METHODS: Material was obtained from two European cases of PAL. Immunocytochemical analysis was performed using antibodies against CD45, CD20, CD79a, CD45RAA, CD3, CD43, CD45RO (UCHL1), CD30, BCL-2, CD68, epithelial membrane antigen (EMA), BCL-6, p53, Ki-67, kappa light chain, lambda light chain, and the EBV antigens latent membrane protein 1 (LMP-1) and EBV encoded nuclear antigen 2 (EBNA-2). The cases were examined for HHV-8 by means of polymerase chain reaction in situ hybridisation (PCR-ISH), solution phase PCR, in situ hybridisation (ISH), and real time quantitative TaqMan PCR to HHV-8 open reading frame 26 (ORF-26) and viral (v) cyclin encoding regions. The expression profile of HHV-8 in PAL and in BC-1 and BC-3 cells was assessed by RNA TaqMan PCR to the HHV-8 genes encoding v-cyclin, v-IL-6, and G protein coupled receptor (GPCR). RESULTS: Both cases expressed CD24, CD20, CD79a, BCL-2, light chain restriction, and high Ki-67 staining. EBV was identified by EBER-ISH in one case. HHV-8 was not identified by solution phase PCR, but was detected by PCR-ISH (sensitivity of 1 viral genome copy/cell) in 35% of the cells and by TaqMan PCR, which showed 50-100 HHV-8 copies/2,000 cell genome equivalents (sensitivity of 1 viral genome in 10(6) contaminating sequences). HHV-8 v-IL-6, v-cyclin, and GPCR encoded transcripts were identified using RNA TaqMan PCR. v-IL-6 was high in PAL and in BC-1 and BC-3 cells. CONCLUSION: The presence of HHV-8 in one of two patients with PAL raises interesting questions in relation to the pathobiology of the condition. Clearly, the results indicate that HHV-8 is not an obligate pathogen, necessary for the effusion phenotype, but might contribute to it by its secretion of specific cytokines.