Transplant glomerulopathy is a late complication of renal transplantation. The characteristic morphology of transplant glomerulopathy includes thickening of glomerular capillary loops with double contour, and duplication of glomerular basement membrane on electron microscopy. Clinical and experimental evidences support the role of antibody-mediated immune mechanism in the development of transplant glomerulopathy. Antibody-induced endothelial cell injury is the key pathogenesis of transplant glomerulopathy. The evolution of transplant glomerulopathy in the context of immunologic injury is briefly reviewed.
Capillaries ; Endothelial Cells ; Glomerular Basement Membrane ; Graft Rejection ; Immunity, Humoral ; Kidney Glomerulus ; Kidney Transplantation ; Microscopy, Electron ; Transplants

Tubulointerstitial nephritis (TIN) is the most common form of renal involvement in IgG4-related disease. It is characterized by a dominant infiltrate of IgG4-positive plasma cells in the interstitium and storiform fibrosis. Demonstration of IgG4-positive plasma cells is essential for diagnosis, but the number of IgG4-positive cells and the ratio of IgG4-positive/IgG-positive plasma cells may vary from case to case and depending on the methods of tissue sampling even in the same case. IgG4-positive plasma cells can be seen in TIN associated with systemic lupus erythematosus, Sjogren syndrome, or anti-neutrophil cytoplasmic antibody-associated vasculitis, which further add diagnostic confusion and difficulties. To have a more clear view of IgG4-TIN and to delineate differential points from other TIN with IgG4-positive plasma cell infiltrates, clinical and histological features of IgG4-TIN and its mimickers were reviewed. In the rear part, cases suggesting overlap of IgG4-TIN and its mimickers and glomerulonephritis associated with IgG4-TIN were briefly described.
Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis ; Diagnosis ; Fibrosis ; Glomerulonephritis ; Glomerulonephritis, Membranous ; Lupus Erythematosus, Systemic ; Lupus Nephritis ; Nephritis, Interstitial* ; Plasma Cells ; Sjogren's Syndrome ; Tin

The tonsillolith is a white or yellow colored calcified lesion that forms in the crypts of the palatine tonsil. Small tonsilloliths are frequently found on tonsils, while giant tonsilloliths are a rare clinical entity. We had a 35-years old female patient, who presented throat discomfort due to a giant tonsillolith. The stone was removed and tonsillectomy was performed. We reviewed the literature on this rare clinical entity.
Female ; Humans ; Palatine Tonsil ; Pharynx ; Tonsillectomy

C3 glomerulopathy is a renal disorder involving dysregulation of alternative pathway complement activation. In most instances, a membranoproliferative pattern of glomerular injury with a prevalence of C3 deposition is observed by immunofluorescence microscopy. Dense deposit disease (DDD) and C3 glomerulonephritis (C3GN) are subclasses of C3 glomerulopathy that are distinguishable by electron microscopy. Highly electron-dense transformation of glomerular basement membrane is characteristic of DDD. C3GN should be differentiated from post-infectious glomerulonephritis and other immune complex-mediated glomerulonephritides showing C3 deposits.
Complement Activation ; Complement Pathway, Alternative ; Dichlorodiphenyldichloroethane ; Glomerular Basement Membrane ; Glomerulonephritis ; Glomerulonephritis, Membranoproliferative ; Microscopy, Electron ; Microscopy, Fluorescence ; Pathology ; Prevalence

A rhabdoid cholangiocarcinoma is a very rare variant of sarcomatous cholangiocarcinomas. Here, we report a vimentin positive cholangiocarcinoma showing rhabdoid features in the entire tumor, with a very aggressive behavior. A 41-year-old woman was admitted to our hospital due to a huge hepatic mass. The resected liver revealed a 17x15cm sized solid mass with extensive necrosis and an infiltrative border. On microscopic examination, the entire tumor was composed of loosely cohesive round to polygonal cells, with rhabdoid features having abundant eosinophilic glassy cytoplasm and eccentrically located vesicular nuclei. Some tumor cells contained intracytoplasmic mucin vacuoles, but definite areas of glandular differentiation or spindle cell were not found. Immunohistochemical staining showed a diffuse strong positive reaction to pan-cytokeratin and vimentin, and focal positivity for the carcinoembryonic antigen. Other immunohistochemical stainings for cytokeratin 7, cytokeratin 20, S-100 protein, HMB-45, desmin, alpha-smooth muscle actin, c-kit, CD34, alpha-fetoprotein, anti-hepatocyte antigen, chromogranin and synaptophysin were all negative. After two months, the patient developed a local recurrence along the resection margin, and multiple hematogenous metastases to the lung and liver were seen on the follow-up CT scan.
Adult ; Cholangiocarcinoma/chemistry/*pathology ; Female ; Human ; Liver Neoplasms/chemistry/*pathology ; Magnetic Resonance Imaging ; Prognosis ; Rhabdoid Tumor/chemistry/*pathology ; Support, Non-U.S. Gov't ; Tomography, X-Ray Computed ; Vimentin/analysis

Focal segmental glomerulosclerosis (FSGS) is characterized by focal and segmental obliteration of glomerular capillary tufts with increased matrix. FSGS is classified as collapsing, tip, cellular, perihilar and not otherwise specified variants according to the location and character of the sclerotic lesion. Primary or idiopathic FSGS is considered to be related to podocyte injury, and the pathogenesis of podocyte injury has been actively investigated. Several circulating factors affecting podocyte permeability barrier have been proposed, but not proven to cause FSGS. FSGS may also be caused by genetic alterations. These genes are mainly those regulating slit diaphragm structure, actin cytoskeleton of podocytes, and foot process structure. The mode of inheritance and age of onset are different according to the gene involved. Recently, the role of parietal epithelial cells (PECs) has been highlighted. Podocytes and PECs have common mesenchymal progenitors, therefore, PECs could be a source of podocyte repopulation after podocyte injury. Activated PECs migrate along adhesion to the glomerular tuft and may also contribute to the progression of sclerosis. Markers of activated PECs, including CD44, could be used to distinguish FSGS from minimal change disease. The pathogenesis of FSGS is very complex; however, understanding basic mechanisms of podocyte injury is important not only for basic research, but also for daily diagnostic pathology practice.
Actin Cytoskeleton ; Age of Onset ; Capillaries ; Diaphragm ; Epithelial Cells ; Foot ; Glomerulosclerosis, Focal Segmental* ; Nephrosis, Lipoid ; Pathology ; Permeability ; Podocytes ; Rabeprazole ; Sclerosis ; Wills

BACKGROUND: Tissue microarray analysis (TMA) is a high-throughput method for histologic evaluation, immunohistochemistry, and in situ hybridization using paraffin embedded tissue. Despite its high efficiency as an experimental tool, TMA is limited because it only contains a very small tissue fragment from each case. Therefore, the purpose of this study was to evaluate the validity of TMA in a study of nephrotoxicity caused by immunosuppressants. METHODS: Male Sprague-Dawley rats were treated with vehicle (n=16), cyclosporine (n=23), and cyclosporine plus losartan (n=13) for a maximum of 7 weeks. After animal sacrifice, renal tissues were embedded in paraffin and processed into slides for microscopic examination using conventional methods and the TMA technique. Acute tubular injury, vascular hyaline change, and interstitial fibrosis were scored in both conventional and TMA slides. The number of interstitial macrophages was counted after ED-1 immunohistochemistry and the results also compared between conventional and TMA slides. RESULTS: The degree of acute tubular injury and interstitial fibrosis showed a significant agreement between conventional and TMA methods (kappa value, 0.79 and 1.00, respectively). The number of interstitial macrophages counted in conventional and TMA slides showed a significant correlation as well (r=0.934, P<0.001). However, the degree of vascular hyaline changes showed less agreement between conventional and TMA methods (kappa value, 0.40). CONCLUSIONS: TMA is a useful and reliable method for the study of nephrotoxicity induced by immunosuppressive agents. TMA also reflects the findings of conventional methods, especially for acute and chronic tubular and interstitial changes.
Acute Kidney Injury ; Animals ; Cyclosporine ; Fibrosis ; Humans ; Hyalin ; Immunohistochemistry ; Immunosuppressive Agents ; In Situ Hybridization ; Losartan ; Macrophages ; Male ; Paraffin ; Rats, Sprague-Dawley ; Tissue Array Analysis ; Vascular System Injuries

STUDY DESIGN: We retrospectively reviewed nine patients of lumbar extraforaminal disc herniation which underwent conservative or surgical treatment. OBJECTIVES: We evaluated the clinical characteristics, accuracy of diagnostic methods, and result of conservative or surgical treatment for the lumbar extraforaminal disc herniation. SUMMARY OF BACKGROUND DATA: Lumbar extraforaminal disc herniation represents an important component of lumbar disc herniation because of the difficulty in diagnosis and the difference in clinical characteristics and surgical approaches in contrast to usual intracanalicular disc herniation. MATERIALS AND METHODS: Nine patients which we have experienced from March 1994 to February 1997 were evaluated by physical examination, magnetic resonance imaging, EMG, and disco-enhanced computed tomogram. There were 4 males and 5 females, and average age was 42.4 years. RESULTS: The level of herniation was 4 cases at L4-5 and 5 at L5-S1. Radiating pain was chief complaint but low back pain was absent or mild. Accuracy of disco-enhanced computed tomogram was superior to that of magnetic resonance imaging. The results of conservative treatment were good in 2 cases(40%), fair in 2 cases(40%), and poor in 1 case(20%). And those of surgical treatment including partial laminectomy, medial facetectomy, and discectomy or extraforaminal approach were excellent in 3 cases(75%), good in 1 case(25%) according to the grading of MacNab. CONCLUSIONS: Lumbar extraforaminal disc herniation represents compressive symptoms of upper lumbar root of the involved level characteristically. Location and degree of disc herniation is an important tractor for determining the surgical approach, and disco-enhanced computed tomogram is a definite diagnostic method.
Diagnosis* ; Diskectomy ; Female ; Humans ; Laminectomy ; Low Back Pain ; Magnetic Resonance Imaging ; Male ; Physical Examination ; Retrospective Studies