Search

Bronchus-associated lymphoid tissue (BALT) lymphomas of the lung are uncommon, and diagnosis is often delayed due to the indolent clinical course. Often, adequate samples are difficult to obtain by bronchoscopy with transbronchial biopsy alone. This retrospective study reviewed the diagnosis and treatment of BALT lymphoma cases at our institution over the course of 19 years. Most patients were white, women, and >50 years old; the mean Charlson Comorbidity Index at the time of diagnosis was 6. Seven of 12 patients presented with solitary nodules or multiple nodules. For six cases, initial modalities were nondiagnostic; four subsequently underwent surgical biopsy, one underwent computed tomography–guided biopsy, and one underwent navigational bronchoscopy for final diagnosis of BALT lymphoma. Ultimately, 55% of cases were diagnosed with nonsurgical biopsy. One patient suffered a pneumothorax related to the initial diagnostic attempt. Ten patients received chemotherapy, radiation, and/or surgery, and 11 of the 12 are still alive. Our data confirm the previously described indolent behavior of BALT lymphomas and the challenges related to diagnosis. While previous studies have suggested surgical biopsy as the primary modality for obtaining histopathology, navigational bronchoscopy could serve as a safer alternative. [ABSTRACT FROM AUTHOR]

Mycoplasma pneumoniae (Mp) is a leading cause of human community-acquired pneumonia. To investigate the pathogenesis of the infection, 36 gerbils were intranasally inoculated with Mp culture (30 animals) or sterile mycoplasma broth (6 animals) and euthanized from 1 to 5 weeks post infection. A morphological and immunohistochemical study was carried out in all animals to determine the cellular populations present in lung parenchyma. Polyclonal and monoclonal antibodies were used to detect antigens of Mp and CD3, CD4, CD8 and CD79 lymphocytes, as well as cells containing S100 and major histocompatibility complex class II (MHC-II) antigens. There was progressive infiltration of mononuclear cells in the lamina propria of bronchi and bronchioles, and hyperplasia of the bronchus-associated lymphoid tissue (BALT) in the infected animals. BALT contained dendritic cells immunopositive to S100 and MHC-II and numerous CD3, CD4 and CD79 lymphocytes. The immunohistochemical results showed that T lymphocytes, particularly CD4 and CD79 cells, may play a role in the immune response of gerbils against Mp. This experimental model is valuable for investigation of the pathogenesis of Mp infection and may assist in the development of therapeutic strategies. [ABSTRACT FROM AUTHOR]

Summary: Background: Primary Sjögren''s syndrome (pSs) is an autoimmune rheumatic disease that may express in a small number of patients a spectrum of lymphoproliferative diseases. The aim of this study was to describe clinical, imaging and pathology features of the extranodal marginal zone B-cell lymphoma (MZCL) of the lung of mucosa-associated lymphoid tissue (MALT) type in patients with pSs. Methods: All patients () with biopsy proven MZCL of the lung of MALT type diagnosed in a tertiary teaching hospital during the last 7 years were studied. Results: Seven patients had pSs. Almost all patients presented an indolent clinical course, contrasting strongly with the spectacular radiological findings in both chest roentgenograms and computed tomography. Pathology infiltration patterns observed were either nodular, peribronchial–perivascular, alveolar, or interstitial. Immunohistochemical study in all cases showed B cell phenotypes. Immunoglobulin light chain restriction was demonstrated in all patients. Monoclonal IgM(κ) was evident in 5/7, IgM(λ) in 1/7 and IgG (κ) in 1/7 of patients. Conclusions: Lung MZCL associated with pSs are characterized by an important dissociation between clinical expression and radiological pattern. Clinical presentation and imaging features are not specific. Therefore, histologic documentation is mandatory to ensure diagnosis. Various chemotherapeutic agents in combination with rituximab lead to partial or complete remission in the majority of patients. [Copyright &y& Elsevier]