Manejo actual de los linfomas / Current concepts: management of lymphomas

Lymphomas constitute a heterogeneous group of neoplastic diseases of the lymphatic system. Between all the varieties of malignancies, lymphomas show problems and special opportunities for the diagnosis and detections. The existence of numerous histologic subtypes and the similarity of malignant lymphocytes with the normal lymphocytes in their distinct stages of differentiation and activation, had led to the development of sophisticated diagnosti methods to assist the morphology in the recognition of them. Special considerations are made about the non-Hodgkin's lymphomas and the Epstein-Barr virus. The author also details the classification, the treatment and the epidemiology.

Pulmonary manifestations of primary sjögren’s syndrome.

Sjögren's syndrome (SS) is a complex autoimmune exocrinopathy with multifactorial pathogenesis and multisystem manifestation. It is called primary Sjögren's syndrome (PSS) when the manifestations are seen without any other co-existent rheumatic diseases. The incidence of respiratory system involvement varies widely in the reported medical literature, partly due to lack of a universal agreement over the diagnostic criteria of the disease and the type of study methods employed. Respiratory system manifestations are protean; upper airway symptoms are very common and so is the complaint of dry cough. The PSS patients may develop interstitial lung diseases (ILDs) such as usual interstitial pneumonia (UIP), non-specific interstitial pneumonia (NSIP), lymphocytic interstitial pneumonia (LIP), bronchiolitis obliterans and organising pneumonia (BOOP), etc. They may also develop the whole spectrum of lymphoproliferative disorders of the lung ranging from LIP to follicular bronchiolitis, nodular lymphoid hyperplasia and low-grade lymphomas. Therapeutic options include symptomatic and supportive measures and corticosteroids as the mainstay of the treatment for ILDs occurring in these patients. In recent years, rituximab (anti-CD20) has emerged as a promising treatment for this disease, though data from controlled trials are still lacking. Pulmonary involvement may be a source of significant morbidity in these patients, though only rarely, it is the cause of death.

Epstein-Barr virus nuclear antigen-2 detection and typing in immunocompromised children correlated with lymphoproliferative disorder biopsy findings

Epstein-Barr virus (EBV), the causative agent of infectious mononucleosis, plays a significant role as a cofactor in the process of tumorigenesis, and has consistently been associated with a variety of malignancies especially in immunocompromised patients. Forty-four children and adolescents (21 liver transplant patients, 7 heart transplant, 5 AIDS, 3 autoimmune hepatitis, 2 nephritic syndromes, 2 medullar aplasia, 2 primary immunodeficiency disorder patients, 1 thrombocytopenic purpura and 1 systemic lupus erythematosus) presenting with chronic active EBV infection (VCA-IgM persistently positive; VCA-IgG > 20 AU/mL and positive IgG _ EBNA) had peripheral blood samples obtained during clinically characterized EBV reactivation episodes. DNA samples were amplified in order to detect and type EBV on the basis of the EBNA-2 sequence (EBNA2 protein is essential for EBV-driven immortalization of B lymphocytes). Although we have found a predominance of type 1 EBNA-2 virus (33/44; 75 percent), 10 patients (22.73 percent) carried type 2 EBNA-2, and one liver transplant patient (2.27 percent) a mixture of the two types, the higher proportion of type 2 EBV, as well as the finding of one patient bearing the two types is in agreement with other reports held on lymphoproliferative disorder (LPD) patients, which analyzed tumor biopsies. We conclude that EBNA-2 detection and typing can be performed in peripheral blood samples, and the high prevalence of type 2 in our casuistic indicates that this population is actually at risk of developing LPD, and should be monitored.

Imunofenotipagem e rearranjo gênico em doenças pulmonares linfocíticas e linfoproliferativas / Immunophenotyping and gene rearrangement analysis in lymphoid/lymphoproliferative disorders of the lungs

OBJETIVO: Determinar a utilidade, na prática rotineira, da análise da clonalidade dos linfócitos T e B nos tecidos pulmonares por reação em cadeia da polimerase no diagnóstico das doenças linfoproliferativas pulmonares. MÉTODOS: Avaliaram-se, mediante análise imunohistoquímica e rearranjo molecular dos genes, 8 casos de pneumonia intersticial linfocítica (PIL) e 7 casos de doenças linfoproliferativas pulmonares. RESULTADOS: Todos os 8 casos de PIL expressaram imunocoloração moderada a forte para CD3, em contraste com apenas 2 casos de linfoma e 1 caso de pseudolinfoma. Rearranjo gênico foi detectado em 4 de 8 casos de PIL, o que mudou o diagnóstico de PIL para linfoma, indicando, assim, a importância da detecção de rearranjo gênico em casos de PIL. Nesta situação, rearranjo gênico usando-se os pares de primers VH/JH e Vgama11/Jgama12 foi detectado em 3 e 1 casos de PIL, respectivamente, e não foram detectadas anormalidades gênicas usando-se as pares Dbeta1/Jbeta2 e Vgama101/Jgama12. Uma associação positiva foi detectada entre a intensidade de imunoexpressão CD20 e CD68 e rearranjo gênico usando-se o par de primers VH/JH. Antes do rearranjo gênico, 4 pacientes com PIL morreram rapidamente, enquanto que, após o rearranjo gênico, apenas 1 paciente com PIL morreu. CONCLUSÕES: A detecção de células B e T monoclonais por imunofenotipagem e reação em cadeia da polimerase mostrou impacto no diagnóstico de linfomas pulmonares em pacientes previamente diagnosticados com PIL. Portanto, imunofenotipagem e reação em cadeia da polimerase devem ser incluídas como métodos de 'padrão ouro' na rotina diagnóstica.

OBJECTIVE: To determine the usefulness, in routine practice, of using polymerase chain reaction to analyze B and T lymphocyte clonality in pulmonary tissue as a tool for the diagnosis of pulmonary lymphoproliferative disorders. METHODS: Immunohistochemistry and molecular gene rearrangement analysis were performed in order to assess 8 cases of lymphoid interstitial pneumonia (LIP) and 7 cases of pulmonary lymphoproliferative disorders. RESULTS: All 8 cases of LIP presented moderate to strong immunostaining for CD3, compared with only 2 cases of lymphoma and 1 case of pseudolymphoma (p = 0.02). Gene rearrangement was detected in 4 of the 8 cases, which changed the diagnosis from LIP to lymphoma, showing the importance of gene rearrangement detection in cases of LIP. In this situation, gene rearrangement using the VH/JH and Vgamma11/Jgamma12 primer pairs was detected in 3 cases and 1 case, respectively, and no gene abnormalities were found using the Dbeta1/Jbeta2 and Vgamma101/Jgamma12 primer pairs in any of the cases. A significant positive association was found between the intensity of CD20 and CD68 expression and gene rearrangement using the VH/JH primer pair. Prior to the gene rearrangement, 4 patients with LIP died quickly, whereas only one patient with LIP died after the gene rearrangement. CONCLUSIONS: Detection of monoclonal B and T cells by immunophenotyping and polymerase chain reaction had an impact on the diagnosis of pulmonary lymphomas in patients previously diagnosed with LIP. Therefore, immunophenotyping and polymerase chain reaction should be used as 'gold standard' techniques in routine practice.

Infection by Cryptosporidium sp. in immunocompromised haematological patients

Determinou-se a freqüência de infecção intestinal por Cryptosporidium sp. em 60 pacientes atendidos no Serviço de Hematologia e Hemoterapia da Santa Casa de Misericórdia de São Paulo que apresentavam processos linfoproliferativos (Grupo 1). Como grupo controle (Grupo 2) examinaram-se 59 indivíduos sadios, que habitavam as mesmas localidades e pertenciam a faixa etária semelhante a dos pacientes do Grupo 1. Os exames parasitológicos de fezes revelaram freqüência de infecção por Cryptosporidium sp. de 10 por cento no Grupo 1, enquanto nos controles (Grupo 2) não se evidenciou nenhum caso de infecção por esse coccídeo. Entre os pacientes que eliminavam oocistos de Cryptosporidium sp. apenas um apresentava fezes diarrêicas.

Efecto inmunosupresor in vitro de las lipoproteínas de baja densidad / In vitro inhibition of lymphocyte proliferation by low density lipoproteins

Background: immune cells participate in the formation of atheromatous plate, however little is known about the effects of native or oxidatively modified lipoproteins on these cells. Aim: To study the effects of lipoproteins on in vitro mononuclear cell proliferation. Material and methods: peripheral blood mononuclear cells were obtained from 10 patients with type 2 diabetes mellitus (aged 52 ñ 9 years old with a disease duration of 8.2 ñ 5.7 years and a mean glycosilated hemoglobin of 9.3 ñ 2.2 percent) and 10 non diabetic healthy controls (aged 50.3 ñ 7.1 years old). These were stimulated with phytohemagglutinin (PHA) alone or in the presence of native LDLS, malondialdehyde modified LDLs or glycated LDLs. Proliferation was measured as 3H-thymidine incorporation and expressed as Stimulation Index (SI). Results: SI of patients and healthy subjects, after PHA stimulation were similar: (57.5 ñ 29.8 and 61.1 ñ 23.5) respectively LDLs did not induce proliferation in neither group. Native LDLs produced a 98 percent inhibition of PHA induced proliferation. Malondialdehyde modified and glycated LDLs caused a 50 percent inhibition. The suppressive effect was maintained when lipoproteins were incorporated to culture media 60 min prior or after PHA stimulation. Conclusions: Lipoproteins inhibit in vitro PHA induced peripheral blood mononuclear cell proliferation both in diabetic and in non diabetic subjects

Cytochemical and immunocytochemical studies in some lymphoproliferative disorders

This study was carried out on 40 patients with different lymphoproliferative disorers: 20 patients with acute lymphoblastic leukemia [ALL], 15 patients with non-Hodgkin's lymphoma [NHL], 3 patients with chronic lymphocytic leukemia [CLL] and 2 patients with multiple myeloma [MM]. The study showed that about 80% of BNHL group express CD10 antigen and that T cells sometimes express it. The 2 cases of MM express CD10 and not CD19 although the latter is a B cell restricted antigen. CD3 is expressed on more mature forms of T- lymphocytes than CD7

A linhagem linfóide para correlaçäo com as doenças linfoproliferativas malignas / The lymphoid line for correlation with malignant lymphopioliferative diseases

Faz-se uma síntese dos conhecimentos atuais a respeito da linhagem linfóide normal. Mostra que a evoluçäo nesse campo foi possível às custas da identificaçäo de moléculas nas superfícies das células linfóides, principalmente por intermédio de anticorpos monoclonais. Apresenta esquema da linhagem linfóide com seus principais eixos, T e B, e destaca as diversas etapas de diferenciaçäo desde a célula mais primitiva até a mais "madura". Tece-se comentários sobre as etapas de transformaçäo blástica que tem início após o contato do linfócito com o antígeno. As custas do conhecimento detalhado da linhagem linfóide säo feitas as tipagens das doenças linfoproliferativas malignas