Week 3-Section 2 (Ca-Pigments and Amyloidosis) AIU 2024 PDF

Calcification Pigments Amyloidosis I. PATHOLOGICAL CALCIFICATION Normal Calcium Regulation In normal condtion, calcium salts are deposited only in bones, teeth and mature pineal body. Normal serum calcium level is 9-11 mg % and is regulated by: Parathyroid hormone (↑ serum leve...

Calcification Pigments Amyloidosis I. PATHOLOGICAL CALCIFICATION Normal Calcium Regulation In normal condtion, calcium salts are deposited only in bones, teeth and mature pineal body. Normal serum calcium level is 9-11 mg % and is regulated by: Parathyroid hormone (↑ serum level), calcitonin hormone (serum level). Vitamin D Diet. Intestinal absorption. Kidney function. Osteolytic and osteoblastic activity in bone. Metabolism of calcium Pathological Calcification Def: Deposition of calcium salts in tissues other than bones and teeth and mature pineal body  Pathological calcification Dystrophic Metastatic  Dystrophic calcification Def: Pathological calcification in which calcium is deposited in dying or dead tissues despite normal serum calcium level and normal calcium metabolism. Breakdown of organic phosphates Necrosis or tissue Favor calcium degeneration Release of deposition enzymes Alteration of pH Dystrophic calcification 1. Pathological calcification in which calcium is deposited in dead tissues despite normal serum calcium 2. Area of necrosis 3. Hematoma 4. Thrombus/Atheroma 5. Degenerated tumors (1) Dystrophic Calcification: Pathological Features: Gross picture: The calcified tissue appears opaque white and hard in consistency. The cut surface is finely granular. Microscopic picture: Calcium stains dark blue with haematoxylin.  Dystrophic calcification in Leiomyoma , uterus The calcified tissue appears opaque white and hard in consistency. The cut surface is finely granular. NEA: Fine, chalky-white MP : Amorphous, basophilic Dystrophic calcification tricuspid valve Calcium stains dark blue with haematoxylin. Dystrophic calcification in a blood vessel  (2) Metastatic Calcification Definition: Pathological calcification in which calcium is deposited in normal tissues due to hypercalcemia (supersaturated solution).  (2) Metastatic Calcification: Causes: Elevation of the blood calcium level due to: 1. Increased calcium absorption from the intestine: - Vitamin D intoxication and - Excess bicarbonate intake for treatment of peptic ulcer. 2. Increased calcium mobilization from the bones as in: -hyperparathyroidism primary and secondary, -prolonged immobilization -bone destruction by malignant tumours as multiple myeloma and metastatic carcinoma. 3. Reduced calcium elimination: Renal failure Metastatic calcification Hyperparathyroidism Vitamin D intoxication Renal failure Metastatic cancer in bone Metastatic Calcification Location of calcification: connective tissues (interstitial tissues) of: stomach, kidney, Lung, blood vessels. Metastatic calcification in heart muscle Metastatic calcification in heart muscle 2- Metastatic calcification Effects Renal interstitium causing chronic renal failure Pulmonary alveoli causing abnormal gas diffusion Blood vessel causing ischemia II. Pigments Pigment Naturally colored substances present either as normal constituents or collected in the cells under certain circumstances  Pigments Exogenous Endogenous Inhalation Inoculation Non –HB HB-dervied Anthracosis tatoo derived 1. Exogenous Pigments  Introduced by inhalation, ingestion or inoculation. 1-Anthracosis Carbon Black discoloration of lungs and regional lymph nodes Deposition of carbon in connective tissue either free or within macrophages. Cause: inhalation of carbon or coal dust Anthracosis of lung  alveolar macrophages or interstitial tissue. Anthracosis of LN  sinuses of LN Exogenous pigment 1.Anthracosis Anthracotic lung Anthracosis lung 2-Tatooing: The pigments are introduced into the skin dermis by the needle or sharp instrument They are phagocytosed by dermal macrophages in which pigments reside for life. (II) Endogenous pigments: a) Non-hemoglobin derived pigments: 1) Melanin: -It is endogenous, non hemoglobin-derived brown to black pigments. -It is synthesized by melanocytes and normally present in the skin, choroids and iris of the eye… Disturbance of melanin pigments takes the form of 1. increase or 2.decrease production. Figure 2.15 Compound naevus showing clusters of benign naevus cells in the dermis as well as in lower epidermis. These cells contain coarse, granular, brown-black melanin pigment (II) Endogenous pigments: a) Non-hemoglobin derived pigments: 2) Lipofuscin (Lipochrome, wear and tear pigment): They are endogenous, non hemoglobin-derived, brown pigments present in the cytoplasm, around the nucleus.(perinuclear). They are present in excess in liver and heart of elderly people and debilitated persons. They are produced by peroxidation of lipids in organelles'membranes by free radicals forming indigestible material within the lysosomes. Lipofuscin in heart (II) Endogenous pigments B) Hemoglobin - derived pigments: a) Hemosiderin pigments: They are endogenous, hemoglobin-derived, iron containing pigments. They are golden yellow to brown pigments, normally present in small amounts in macrophages of liver, spleen and bone marrow (reticulo-endothelial system that is responsible for destruction of old RBCs). Hemosiderin pigment inside alveolar macrophages in chronic venous congestion of the lung (endogenous pigment) (II) Endogenous pigments B) Hemoglobin - derived pigments: b) Bilirubin: They are endogenous, hemoglobin-derived, iron free pigments. They are golgen yellow to green pigments normally present in blood up to 1mg % Their serum level increases due to: Excess production as in hemolytic anemia. Decrease uptake and utilization by liver. Decrease excretion in intestine caused by bile duct obstruction. Increase serum level leads to jaundice. Jaundice: means yellowish coloration of skin and sclera of eye associated with increase serum bilirubin levels. III. Amyloidosis Amyloidosis Amyloidosis is the term used for a group of diseases characterized by extracellular deposition of fibrillar insoluble proteinaceous substance called amyloid. AMYLOIDOSIS Grossly: Homogenous, Semitranslucent, Pale, waxy, gray Amyloidosis liver Amyloidosis By H&E staining under light microscopy: amyloid appears as extracellular, homogeneous, structureless and eosinophilic hyaline material. Congo red staining : Salmon pink and shows apple-green birefringence on polarising microscopy. Liver amyloidosis Amyloidosis Renal amyloidosis in BVs and glomeruli , congo red stain  Amyloidosis Chemical nature of amyloid deposits: Two chemically distinct major classes of amyloid fibrillar proteins have been identified. Amyloid light chain (AL): It is derived from plasma cells (immumocytes) and contains Ig light chains. Amyloid associated (AA): is a non immunoglobulin protein synthesised by the liver. Other proteins are transthyretin, B2-microglobulin and B2- amyloid proteins.  Primary systemic amyloidosis: The distribution is found mainly in the heart, kidney, G.I.T, peripheral nerves, skin and tongue. The amyloid deposit is that of AL. It is seen in 5-15% of patients with plasma cell myeloma. Secondary (reactive) systemic amyloidosis: The distribution is found mainly in kidneys, liver, spleen, L.Ns, adrenals and thyroid. The amyloid deposit is AA. It is seen in chronic inflammatory states as: Osteomyelitis. Rheumatoid arthritis. Tuberculosis, and leprosy. Inflammatory bowel diseases (IBD). Clinical and pathological effects Amyloid deposition In blood vessels leading Pressure on adjacent to cells narrowing Leading to atrophy &increased permeability PART 2: Practical 2 I. PATHOLOGICAL CALCIFICATION Dystrophic calcification in Leiomyoma , uterus Dystrophic calcification in a blood vessel II. Pigments Anthracotic lung Anthracosis lung Anthracosis lung Figure 2.15 Compound naevus showing clusters of benign naevus cells in the dermis as well as in lower epidermis. These cells contain coarse, granular, brown-black melanin pigment Lipofuscin in heart Hemosiderin pigment inside alveolar macrophages in chronic venous congestion of the lung (endogenous pigment) III. Amyloidosis  Liver amyloidosis Grossly: Homogenous, Semitranslucent, Pale, waxy, gray + iodine  brown + sulphuric acid  bluish violet Amyloidosis liver Liver amyloidosis Amyloidosis Good Luck!