Diseases of ImmunityDiseases of Immunity

CS # 87 - Acute proliferative post CS # 87 - Acute proliferative post streptococcalstreptococcal

This glomerulus is hypercellular and capillary loops are poorly defined. This is a type of proliferative glomerulonephritis known as post-infectious glomerulonephritis. This case followed a group A beta hemolytic streptococcal infection of the pharynx 3 weeks earlier.

CS # 87 - Acute proliferative post CS # 87 - Acute proliferative post streptococcalstreptococcal

The hypercellularity of post-infectious glomerulonephritis is due to increased numbers of epithelial, endothelial, and mesangial cells as well as neutrophils in and around the glomerular capillary loops. This disease may follow several weeks after infection with certain strains of group A beta hemolytic streptococci. Patients who have had a strep infection typically have an elevated anti-streptolysin O (ASO) titer.

CS # 42 - TB, lungsCS # 42 - TB, lungs

Well-defined granulomas are seen here. They have rounded outlines. The one toward the center of the photograph contains several Langhans giant cells. Granulomas are composed of transformed macrophages called epithelioid cells along with lymphocytes, occasional PMN's, plasma cells, and fibroblasts. The localized, small appearance of these granulomas suggests that the immune response is fairly good.

CS # 42 - TB, lungsCS # 42 - TB, lungs

At low magnification, this photomicrograph reveals multiple granulomas. Granulomatous disease by chest radiograph can appear as reticulonodular densities.

CS # 42 - TB LungsCS # 42 - TB Lungs

The edge of a granuloma is shown here at high magnification. At the upper right is amorphous pink caseous material composed of the necrotic elements of the granuloma as well as the infectious organisms. This area is ringed by the inflammatory component with epithelioid cells, lymphocytes, and fibroblasts.

CS # 42 - TB, lungsCS # 42 - TB, lungs

At high magnification, the granuloma demonstrates that the epithelioid macrophages are elongated with long, pale nuclei and pink cytoplasm. The macrophages organize into committees called giant cells. The typical giant cell for infectious granulomas is called a Langhans giant cell and has the nuclei lined up along one edge of the cell. The process of granulomatous inflammation takes place over months to years (did you ever hear of a committee action that was completed in a short time?)

CS # - Lupus eryhtematosus, SpleenCS # - Lupus eryhtematosus, Spleen

The periarteriolar fibrosis ("onion skinning") seen in the spleen in patients with SLE at autopsy is quite striking, though of no major clinical consequence. This results from vasculitis.

CS # 253 – Lupus erythematosus, CS # 253 – Lupus erythematosus, kidneykidney

One of the feared complications of the autoimmune diseases is renal failure. This is most likely to occur with SLE and the diffuse form of scleroderma. Here is a glomerulus in which the capillary loops are markedly pink and thickened such that capillary lumens are hard to see. This is characteristic for lupus nephritis.

CS # 253 – Lupus erythematosus, CS # 253 – Lupus erythematosus, kidneykidney

Here is a glomerulus with thickened pink capillary loops, the so-called "wire loops", in a patient with lupus nephritis. The surrounding renal tubules are unremarkable.