Amyloidosis of the kidney
Microscopicallyamyloid deposits are found principally in the glomeruli
but they also are present in the interstitial peritubular tissue
as well as in the walls of the blood vessels.
The interstitial peritubular deposits frequently are associated with the appearance of amorphous pink casts within the tubular lumens, presumably of a proteinaceous nature.
The most commonly used staining technique uses the dye Congo red, which under ordinary light imparts a pink or red color to amyloid deposits. Under polarized ight the Congo red–stained amyloid shows socalled apple-green birefringence
Hashimoto Thyroiditis
most common cause of hypothyroidism in locations where iodine levels are sufficient.
It is characterized by insidious thyroid failure
most prevalent between ages 45 and 65 years
with a 10:1 to 20:1 female predominance.
Morphology
Grossly: The thyroid is typically diffusely enlarged with pale parenchyma and an intact capsule.
Microscopically: Lesions exhibit an exuberant infiltrate of lymphocytes, plasma cells, and macrophages; occasional germinal centers; atrophic follicles with eosinophilic granular cytoplasm in residual follicular cells (Hu¨rthle cells); and delicate fibrosis.
Clinical Course
Hashimoto thyroiditis presents with painless thyroid enlargement usually associated with some degree of hypothyroidism.
Hyperthyroidism (hashitoxicosis) can be seen early but is transient.
Patients have an increased risk of developing other autoimmune diseases (e.g., type 1 diabetes, autoimmune adrenalitis, systemic lupus erythematosus).
There is a small risk of subsequent B-cell non-Hodgkin lymphoma.