ABSTRACT
An 84-year-old woman with IgG4-related disease presented with jaundice and liver dysfunction after coronavirus disease 2019 (COVID-19) vaccination. Serum IgG4 levels were elevated. Diagnostic imaging showed no stenotic lesions in the bile ducts. A liver biopsy was performed because of the enlarged liver. Infiltration of IgG4-positive plasma cells, which accounted for approximately 74% of total plasma cells, was found in the portal area, but there was no evidence of periportal hepatitis, and inflammatory cell infiltration into the lobular space was minimal. IgG4-related hepatopathy was diagnosed. The patient achieved spontaneous remission with no treatment and only follow-up and remains under observation at the time of writing.
Subject(s)
COVID-19 Vaccines , COVID-19 , Immunoglobulin G4-Related Disease , Liver Diseases , Aged, 80 and over , Female , Humans , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Immunoglobulin G , Immunoglobulin G4-Related Disease/pathology , Liver Diseases/etiologyABSTRACT
The distribution of LH-RH-positive nerve fibers in the median eminence was demonstrated in the 1970s and 1980s. A few LH-RH fibers have been reported to be present in the adjacent pars tuberalis of the pituitary, but their functional significance has not been clarified and still remains enigmatic. Adult male Wistar-Imamichi rats were separated into two groups: one for immunohistochemistry of LH-RH and S-100 protein (for the identification of folliculo-stellate cells) and the other for electron microscopy. For both immunohistochemistry and electron microscopy, the specimens obtained contained the pituitary gland connected with the hypothalamus. Numerous LH-RH-positive fibers were observed as tiny lines with several varicosities both on the primary vascular plexus and in the hypothalamus corresponding to the posterior half of the portal vein area. LH-RH-positive fibers were also noted around S-100-positive cells in the pars tuberalis. Weakly reactive S-100 cells were scattered in the pars tuberalis in the midsagittal plane, while clusters of strong reactive elements occurred 100-300 microm from the center. Similar observations were made using fluorescence immunohistochemistry for LH-RH and S-100, and at the electron-microscopic level. At the posterior portion of the portal vein system, bundles of the LH-RH-immunoreactive fibers invaded the pars tuberalis and terminated on agranular cells. Gap junctions were clearly seen among agranular cells corresponding to folliculo-stellate cells. It is postulated that the LH-RH message might be transmitted not only by the established hypophyseal portal vein system but also via the folliculo-stellate cells in the pars tuberalis to aid in the modulation of LH release.
