microgranuloma

microgranuloma

(1) A term of art referring to an aggregate of  less than 25 epithelioid histiocytes, usually seen between germinal centres in lymphoid tissue with toxoplasmosis.
(2) A small collection of epithelioid histiocytes which, while nonspecific alone, in the appropriate setting is regarded as characteristic of HIV encephalitis if found in the brain of a patient with AIDS, Crohn’s disease or non-alcoholic fatty liver disease.
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Sinusoidal congestion (in hepatic parenchyma), degenerative changes of hepatocytes, cellular swelling, vacuolar changes with granular cytoplasm of hepatocytes, necrotic changes of hepatic parenchyma, loss of nucleus, fragmentation of nuclei, centrilobular, midzonal necrosis, bile duct hyperplasia, perivascular lymphoid aggregation, infiltration of mononuclear cells (MNC), formation of microgranuloma, fatty liver (lipid deposition in hepatocyte), and steatosis were graded as the following: no abnormality detected (NAD), minimal pathological changes (+), mild pathological changes (++), moderate pathological changes (+++), and severe pathological changes (++++).
Additional findings included extensive, acute renal hemorrhage and a single microgranuloma adjacent to a parabronchus in the lung.
D, Lobular-based EBV microgranulomas (hematoxylin-eosin, original magnifications X10 [A and D], X20 [B], and 40 [C]).
When fever and lymph node enlargement persists, often it ends in biopsy studies and the common histological picture is necrosis with microgranulomas. In majority of cases, the clinical course is benign and symptoms and signs resolve within a few weeks.
Dodatkowe badania histopatologiczne ujawnily, ze chociaz u szczurow narazanych na stezenie 0,5 mg/[m.sup.3] i wieksze nie wykryto zwiekszonej liczby wlokien kolagenu w scianach pecherzykow, to jednak nieznaczne zwiekszenie kolagenu wystapilo w mikroziarnach (microgranulomas).
Los microgranulomas se formaron especificamente en respuesta a la infeccion con M.
In view of carcinogenicity of CNTs, SWCNTs were directly instilled into the lungs of the animals, it was found that exposure to SWCNTs at a high concentration leads to the development of granulomas in rodents and a concentration of 0.5 mg/[m.sup.3] and 2.5 mg/[m.sup.3] for MWCNTs induces microgranulomas with the inflammation in the alveoli [158-160].
The presence of lepra bacilli and microgranulomas composed of foamy macrophages, plasma cells and lymphocytes interfering with the normal functioning of the bone marrow could be responsible for the pancytopenia, which resolved within 2 weeks of initiation of anti-leprosy treatment.
Occasional Langerhans cell microgranulomas were seen.
From these exposures, C3H/HeJ and MJ mice, but not BALB/c or C57BL/6 mice, developed T-cell alveolitis, and a subset of these mice developed spontaneously resolving pulmonary microgranulomas. Beryllium-specific lymphocyte proliferation following the epicutaneous administration of beryllium salts was not evaluated.
* Microgranulomas. Some have defined these as 3 to 7 cells in cross-section, often admixed with other inflammatory cells and/or apoptotic hepatocytes.
Immunohistochemical staining for CD68 highlighted numerous macrophages, with a dominance of CD4 lymphocytes in proximity to the microgranulomas. CD31 staining of vascular endothelium confirmed the presence of intravascular silicone particles.