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Journal of Clinical and Experimental... 2012In this review, representative types of granulomatous lymphadenitis (GLA) are described. GLA can be classified as noninfectious GLA and infectious GLA. Noninfectious GLA... (Review)
Review
In this review, representative types of granulomatous lymphadenitis (GLA) are described. GLA can be classified as noninfectious GLA and infectious GLA. Noninfectious GLA includes sarcoidosis and sarcoid-like reaction. The cause of sarcoidosis remains unknown, but it has good prognosis. Sarcoid-like reaction, which is considered to be a biological defense mechanism, is observed in regional lymph nodes with many underlying diseases. Infectious GLA can be classified as suppurative lymphadenitis (LA) and nonsuppurative LA. Suppurative LA generally shows follicular hyperplasia and sinus histiocytosis in the early phase. In tularemia and cat scratch disease, monocytoid B lymphocytes (MBLs) with T cells and macrophages contribute to the formation of granuloma. However, none of the epithelioid cell granulomas of Yersinia LA contains MBLs like in cat scratch disease. In addition, almost all have a central abscess in granulomas induced by Gram-negative bacteria. In terms of the lymph nodes, tularemia and cat scratch disease are apt to affect the axillary and cervical regions while Yersinia LA affects the mesenteric lymph node. Nonsuppurative LA includes tuberculosis and BCG-histiocytosis. These are induced by delayed allergic reaction of M. tuberculosis. Tuberculosis LA mainly appears in the cervical lymph node. Organisms are histologically detected by Ziehl-Neelsen staining in the necrotic area. Toxoplasmosis is also a nonsuppurative protozoan infection (Toxoplasma gondii). In toxoplasma LA, MBLs can also be seen, but round and organized, well-formed granulomas are not found in this disease. Furthermore, necrosis is not induced and there are no accompanying neutrophils, eosinophils and fibrosis. GLA described above is associated with characteristic histological findings. An accurate pathological diagnosis using the above findings can lead to precise treatment.
Topics: Animals; Cat-Scratch Disease; Gram-Negative Bacterial Infections; Granuloma; Humans; Lymph Nodes; Sarcoidosis
PubMed: 22706525
DOI: 10.3960/jslrt.52.1 -
Archives of Pathology & Laboratory... May 2010Granulomas are among the most commonly encountered abnormalities in pulmonary pathology and often pose a diagnostic challenge. Although most pathologists are aware of... (Review)
Review
CONTEXT
Granulomas are among the most commonly encountered abnormalities in pulmonary pathology and often pose a diagnostic challenge. Although most pathologists are aware of the need to exclude an infection in this setting, there is less familiarity with the specific histologic features that aid in the differential diagnosis.
OBJECTIVE
To review the differential diagnosis, suggest a practical diagnostic approach, and emphasize major diagnostically useful histologic features. This review is aimed at surgical pathologists who encounter granulomas in lung specimens.
DATA SOURCES
Pertinent recent and classic peer-reviewed literature retrieved from PubMed (US National Library of Medicine) and primary material from the institutions of both authors.
CONCLUSIONS
Most granulomas in the lung are caused by mycobacterial or fungal infection. The diagnosis requires familiarity with the tissue reaction as well as with the morphologic features of the organisms, including appropriate interpretation of special stains. The major noninfectious causes of granulomatous lung disease are sarcoidosis, Wegener granulomatosis, hypersensitivity pneumonitis, hot tub lung, aspiration pneumonia, and talc granulomatosis.
Topics: Bronchoscopy; Diagnosis, Differential; Granuloma; Humans; Lung; Lung Diseases
PubMed: 20441499
DOI: 10.5858/134.5.667 -
American Journal of Physiology. Cell... Nov 2022() is the pathogen that causes tuberculosis (TB), a leading infectious disease of humans worldwide. One of the main histopathological hallmarks of TB is the formation... (Review)
Review
() is the pathogen that causes tuberculosis (TB), a leading infectious disease of humans worldwide. One of the main histopathological hallmarks of TB is the formation of granulomas comprised of elaborately organized aggregates of immune cells containing the pathogen. Dissemination of from infected cells in the granulomas due to host and mycobacterial factors induces multiple cell death modalities in infected cells. Based on molecular mechanism, morphological characteristics, and signal dependency, there are two main categories of cell death: programmed and nonprogrammed. Programmed cell death (PCD), such as apoptosis and autophagy, is associated with a protective response to by keeping the bacteria encased within dead macrophages that can be readily phagocytosed by arriving in uninfected or neighboring cells. In contrast, non-PCD necrotic cell death favors the pathogen, resulting in bacterial release into the extracellular environment. Multiple types of cell death in the PCD category, including pyroptosis, necroptosis, ferroptosis, ETosis, parthanatos, and PANoptosis, may be involved in infection. Since PCD pathways are essential for host immunity to , therapeutic compounds targeting cell death signaling pathways have been experimentally tested for TB treatment. This review summarizes different modalities of -mediated host cell deaths, the molecular mechanisms underpinning host cell death during infection, and its potential implications for host immunity. In addition, targeting host cell death pathways as potential therapeutic and preventive approaches against infection is also discussed.
Topics: Humans; Tuberculosis; Mycobacterium tuberculosis; Cell Death; Macrophages; Granuloma; Host-Pathogen Interactions
PubMed: 36189975
DOI: 10.1152/ajpcell.00246.2022 -
The Journal of Experimental Medicine Jun 2023The hallmark of tuberculosis (TB) is the formation of immune cell-enriched aggregates called granulomas. While granulomas are pathologically diverse, their tissue-wide...
The hallmark of tuberculosis (TB) is the formation of immune cell-enriched aggregates called granulomas. While granulomas are pathologically diverse, their tissue-wide heterogeneity has not been spatially resolved at the single-cell level in human tissues. By spatially mapping individual immune cells in every lesion across entire tissue sections, we report that in addition to necrotizing granulomas, the human TB lung contains abundant non-necrotizing leukocyte aggregates surrounding areas of necrotizing tissue. These cellular lesions were more diverse in composition than necrotizing lesions and could be stratified into four general classes based on cellular composition and spatial distribution of B cells and macrophages. The cellular composition of non-necrotizing structures also correlates with their proximity to necrotizing lesions, indicating these are foci of distinct immune reactions adjacent to necrotizing granulomas. Together, we show that during TB, diseased lung tissue develops a histopathological superstructure comprising at least four different types of non-necrotizing cellular aggregates organized as satellites of necrotizing granulomas.
Topics: Humans; Tuberculosis; Granuloma; Lung; Macrophages; Mycobacterium tuberculosis
PubMed: 36920308
DOI: 10.1084/jem.20221392 -
Annals of Medicine Dec 2022Sarcoidosis is a heterogeneous disease, which can affect virtually every body organ, even though lungs and intra thoracic lymph nodes are almost universally affected.... (Review)
Review
Sarcoidosis is a heterogeneous disease, which can affect virtually every body organ, even though lungs and intra thoracic lymph nodes are almost universally affected. The presence of noncaseating granulomas is the histopathological hallmark of the disease, and clinical picture depends on the organs affected. Data about interaction between sarcoidosis and comorbidities, such as cardiovascular and pulmonary diseases, autoimmune disorders, malignancy and drug-related adverse events are limited. Several lung conditions can be associated with sarcoidosis, such as pulmonary hypertension and fibrosis, making it difficult sometimes the differentiation between complications and distinctive pathologies. Their coexistence may complicate the diagnosis of sarcoidosis and contribute to the highly variable and unpredictable natural history, particularly if several diseases are recognised. A thorough assessment of specific disorders that can be associated with sarcoidosis should always be carried out, and future studies will need to evaluate sarcoidosis not only as a single disorder, but also in the light of possible concomitant conditions.Key messagesComorbidities in sarcoidosis are common, especially cardiovascular and pulmonary diseases.In the diagnostic workup, a distinction must be made between sarcoidosis-related complaints and complaints caused by other separate disorders. It can be very difficult to distinguish between complications of sarcoidosis and other concomitant conditions.The coexistence of multiple conditions may complicate the diagnosis of sarcoidosis, affect its natural course and response to treatment.
Topics: Granuloma; Humans; Lung; Lung Diseases; Sarcoidosis
PubMed: 35441568
DOI: 10.1080/07853890.2022.2063375 -
Gaceta Medica de Mexico 2019Granulomas are circumscribed lesions mainly composed of mononuclear cells that arise in response to poorly degradable antigenic stimuli. They are found in 2-15 % of... (Review)
Review
Granulomas are circumscribed lesions mainly composed of mononuclear cells that arise in response to poorly degradable antigenic stimuli. They are found in 2-15 % of liver biopsies and the meaning of their finding can range from an incidental phenomenon to the manifestation of a systemic disease of infectious, autoimmune or neoplastic origin. Clinical presentation usually points at the underlying pathology; however, the list of associated conditions is extensive, and differs based on patient epidemiological history and baseline characteristics. The most useful element for their study is a thorough medical history, with an emphasis on recent trips, exposures and consumption of drugs or raw or exotic foods. Detailed histopathological analysis may help identify the etiology. For example, the presence of epithelioid granulomas with caseous necrosis indicates tuberculosis and, its absence, sarcoidosis; eosinophil abundance can be associated with drug reactions or parasitic infections; and the presence of foreign bodies can be the cause of granulomatous liver disease (GLD). In this article, we describe the basic clinical-pathological aspects of GLD, and provide a brief summary of the most common etiologies, with an emphasis on the Latin-American region.
Topics: Animals; Biopsy; Diagnosis, Differential; Granuloma; Humans; Liver Diseases; Sarcoidosis; Tuberculosis
PubMed: 31219474
DOI: 10.24875/GMM.18004327 -
Hepatology Communications Apr 2024A granuloma is a discrete collection of activated macrophages and other inflammatory cells. Hepatic granulomas can be a manifestation of localized liver disease or be a... (Review)
Review
A granuloma is a discrete collection of activated macrophages and other inflammatory cells. Hepatic granulomas can be a manifestation of localized liver disease or be a part of a systemic process, usually infectious or autoimmune. A liver biopsy is required for the detection and evaluation of granulomatous liver diseases. The prevalence of granulomas on liver biopsy varies from 1% to 15%. They may be an incidental finding in an asymptomatic individual, or they may represent granulomatous hepatitis with potential to progress to liver failure, or in chronic disease, to cirrhosis. This review focuses on pathogenesis, histological features of granulomatous liver diseases, and most common etiologies, knowledge that is essential for timely diagnosis and intervention.
Topics: Humans; Liver Diseases; Liver Cirrhosis; Granuloma; Biopsy
PubMed: 38497932
DOI: 10.1097/HC9.0000000000000392 -
Ugeskrift For Laeger Aug 2023Tattoo-associated sarcoidosis is characterized by granulomas in tattoos with or without the involvement of other organ systems such as the lungs and eyes.... (Review)
Review
Tattoo-associated sarcoidosis is characterized by granulomas in tattoos with or without the involvement of other organ systems such as the lungs and eyes. 18F-fluorodeoxyglucose (18F-FDG PET is a nuclear medicine imaging study that can differentiate between metabolically over-active areas and normal tissue. Thus, this review finds that 18F-FDG-PET/CT imaging can be used to image inflammatory activity in tattoos and in case of papulonodular tattoo reaction be used to investigate possible systemic sarcoidosis.
Topics: Humans; Fluorodeoxyglucose F18; Positron Emission Tomography Computed Tomography; Sarcoidosis; Tattooing; Granuloma
PubMed: 37615154
DOI: No ID Found -
Molecular Microbiology Mar 2022The zebrafish has earned its place among animal models to study tuberculosis and other infections caused by pathogenic mycobacteria. This model host is especially useful... (Review)
Review
The zebrafish has earned its place among animal models to study tuberculosis and other infections caused by pathogenic mycobacteria. This model host is especially useful to study the role of granulomas, the inflammatory lesions characteristic of mycobacterial disease. The optically transparent zebrafish larvae provide a window on the initial stages of granuloma development in the context of innate immunity. Application of fluorescent dyes and transgenic markers enabled real-time visualization of how innate immune mechanisms, such as autophagy and inflammasomes, are activated in infected macrophages and how propagating calcium signals drive communication between macrophages during granuloma formation. A combination of imaging, genetic, and chemical approaches has revealed that the interplay between macrophages and mycobacteria is the main driver of tissue dissemination and granuloma development, while neutrophils have a protective function in early granulomas. Different chemokine signaling axes, conserved between humans and zebrafish, have been shown to recruit macrophages permissive to mycobacterial growth, control their microbicidal capacity, drive their spreading and aggregation, and mediate granuloma vascularization. Finally, zebrafish larvae are now exploited to explore cell death processes, emerging as crucial factors in granuloma expansion. In this review, we discuss recent advances in the understanding of mycobacterial pathogenesis contributed by zebrafish models.
Topics: Animals; Granuloma; Larva; Mycobacterium; Tuberculosis; Virulence; Zebrafish
PubMed: 34714579
DOI: 10.1111/mmi.14838 -
The Pan African Medical Journal 2019Sarcoidosis is a multisystem granulomatous disorders of unknown cause, characterised by the presence of epithelioid granulomas and giant-cell granulomas without caseous...
Sarcoidosis is a multisystem granulomatous disorders of unknown cause, characterised by the presence of epithelioid granulomas and giant-cell granulomas without caseous necrosis. Ocular sarcoidosis mainly manifests as bilateral anterior granulomatous uveitis. The involvement of the posterior segment in patients with ocular sarcoidosis is rare and manifests as periphlebitis or choroidal invasion. Isolated papillary edema is uncommon; hence the peculiarity of our case study. Posterior involvement is a prognostic indicator of poor outcome, threatening visual acuity. Early management, in close cooperation with pneumologists and based on systemic corticosteroid therapy, improves visual outcome and reduces complications.
Topics: Eye Diseases; Female; Granuloma; Humans; Middle Aged; Papilledema; Prognosis; Sarcoidosis; Uveitis; Visual Acuity
PubMed: 31223420
DOI: 10.11604/pamj.2019.32.132.18253