Renal Pathology Flashcards

Question

Lab Investigations: Electron Microscopy

Answer 1

Provides high-resolution images of kidney tissue at the ultrastructural level- valuable in diagnosing glomerular diseases and other renal pathologies where ultrastructural changes play a significant role. Provides ultrastructural details. Uses a beam of electrons to visualize cellular and subcellular structures, such as podocyte foot processes, basement membranes, and mesangial cells.

Answer 2

"Ish": Informal term conveying approximation or uncertainty. ‘always (ish@ used to imply occasionalexceptions variations in EM and IMF use for renal biopsy evaluation depending on the specific case/ insitution.

Answer 3

Renal biopsies: removal of small piece of tissue to examin under a microscope to diagnose/assess kidney damage. Cut at "Levels": Kidney tissue samples cut into thin sections at various levels (superficial, deep , midline) so pathologists can examine different regions of the tissue to asses for variations/abnormalities throughout the sample.

Answer 4

Needle Biopsy: Most common type. Needle inserted through skin into the kidney extracting a small tissue sample. Native Kidney Biopsy: Biopsy performed on native kidneys (patient's own kidneys.) Transplant Biopsy: conducted on a transplanted kidney to assess its function or to diagnose any potential issues ( rejection.) Tumor Biopsy: biopsy may be performed to obtain a tissue sample for diagnosis and to determine the type of tumor present if one is suspected Wedge Biopsy: small wedge-shaped piece of tissue is removed from the kidney. Lobe Biopsy: Refers to a biopsy technique where a lobe of the kidney is specifically targeted for sampling. Resection Biopsy: Removal of a portion of the kidney tissue for examination, often used in cases where a larger sample. Explant Biopsy: involves removal of entire kidney (explant) for examination, which may be necessary in cases of severe disease or transplantation.

Answer 5

- Definitive histological gianosis of glomerular/ interstitial disease - Severe Proteinuira - Haematuria not caused by disease of the lower urinary tract: suggests potential renal or glomerular involvement often necessitating renal biopsy for accurate diagnosis. - Acute renal failure (intrinsic renal disease) - Glomerulonephritis - Other glomerular disorders (e.g amyloid and diabetes) - Interstitial Nephritis - Renal Transplant ( assessment post-transplant for rejection/complications

Answer 6

- assesses glomeruluar abnormalities and interstitial diseases by evaluating interstitial inflammation and fibrosis - Needle core biopsy followed by examination under microscopes e.g electron, light and immunoflourescence microscopy. Allows for comprehensive evaluation of kidney tissue providing valuable diagnostic information for guiding patient care.

Answer 7

Tissue preserved in formalin for light microscopy, glutaraldehyde for electron microscopy (EM), and frozen/Michel's medium for immunofluorescence microscopy (IMF) to maintain cellular structure and antigen integrity. -Aldehyde fixatives (e.g formalin and glutaraldehyde), crosslink proteins in tissue samples, preserving cellular structures and preventing degradation for microscopic examination. -Glutaraldehyde in high concentrations can cause irritation to the respiratory tract, skin, and eyes, and prolonged exposure may lead to sensitization and allergic reactions. Pure morphology, better, slower, lot more toxic

Answer 8

Samples embedded : -paraffin for light microscopy -resin for electron microscopy -frozen sections for immunofluorescence microscopy -Prepares samples for respective microscopic examinations while preserving tissue architecture and antigenicity.

Answer 9

Can be global and diffuse Enlarged, hypercellular glomeruli Proliferation of enotherlial and messignal cells Cresent formation in severe cases- impairs kidney function Immune system reacts to bacterial antigens deposited in the glomeruli causing inflammation, cellular proliferation and formation of crescents. this inflammation and damage can progress to chronic kidney disease if left untreated.

Answer 10

permeability of the filtration barrier may be altered, potentially allowing bacterial fragments or whole bacteria to pass the through the filtration barrier, triggering an immune response in the kidney contributing to kidney damage - Activation of inflammatory cells/ release of inflammatory mediators leads to inflammation and renal tissue damage.

Answer 11

Masson trichome: Interstitium stained green Jones Silver Stain: increased cellularity, highlights glomerular basement membrane for evaluation of basement membrane integrity and thickness.

Answer 12

renal interstitium : the space between the renal tubules and blood vessels within the kidney parenchyma. -contains various structures including fibroblasts, collagen fibers, and interstitial fluid, and plays a crucial role in maintaining the structural integrity and function of the kidney.

Answer 13

specialized extracellular matrix structure provides structural support acts as a barrier between epithelial and endothelial tissues.

Answer 14

Diffuse indicating widespread or generalized involvement of the glomerulus/ generalised thickening of glomerular membrane..? and focal indicating localized or limited involvement of the glomerulus

Answer 15

- type of glomerulonephritis characterised by widspread diffuse proliferation of glomerular cells. Usually seen in SLE and post in-fectious glomerulnephritis.

Answer 16

AKA double contour or double basement membrane -characteristic histological feature observed in evaluation of glomerular diseases - Refers to the appearance of an additional layer of the glomeruluar basement membrane (GBM) - seen in certain kidney diseases, particularly those involving immune complex deposition (lupus nephritis) - presence of double contouring indicated immune complex-mediated injury to the glomeruli: immune complexes accumulate along GBM causing formation of an additional layer or thickening of the basement membrane.

Answer 17

Show spikes between subepithelial deposits in the glomerulus and thickening of Glomerular Basement Membrane

Answer 18

- typically associated with membranous glomerulonephritis - this can be caused by various factors e.g auto immune disesases (E.G SLE), infections (hepatitis B/C), certain medications and malignancies

Answer 19

Diabetes mellitus: Chronic high blood sugar levels can lead to thickening of the glomerular basement membrane (GBM) in diabetic nephropathy. Membranous glomerulonephritis: Immune complex deposition along the GBM can cause thickening in membranous glomerulonephritis. Aging: Gradual thickening of the GBM can occur as a natural consequence of aging.

Answer 20

mpaired filtration: Thickening of the GBM can reduce the permeability of the glomerular filtration barrier, leading to impaired filtration of blood and proteinuria. Renal dysfunction: Chronic thickening of the GBM, particularly in conditions like diabetic nephropathy, can contribute to progressive renal dysfunction and decline in kidney function. Glomerulosclerosis: Prolonged thickening of the GBM can lead to glomerulosclerosis, characterized by scarring and loss of functional glomeruli, ultimately leading to end-stage renal disease (ESRD).

Answer 21

-Glomerular filtration barrier in the kidneys selectively filters substances from the blood into the urine while retaining important components in the bloodstream.

Answer 22

Water: The kidneys filter large amounts of water to maintain fluid balance in the body. Waste products: Metabolic waste products such as urea, creatinine, and uric acid are filtered from the blood and excreted in the urine. Electrolytes: Essential ions such as sodium, potassium, chloride, and bicarbonate are filtered and regulated by the kidneys to maintain electrolyte balance. Nutrients: Small molecules such as glucose, amino acids, and vitamins are filtered and reabsorbed by the renal tubules to maintain nutrient balance in the body. Hormones: Some hormones are filtered and excreted by the kidneys, while others are regulated by renal function. Toxins and drugs: Various toxins, drugs, and foreign substances are filtered by the kidneys and excreted in the urine to maintain systemic homeostasis.

Answer 23

- Refers abnormal protein aggregates that accumulate in various tissues and organs disrupting normal function - aggregates consist of misfolded proteins that can form insoluble fibrils leading to tissue damage and dysfunction. - Amyloid depositis can occur in different organs and is associated with various diesases e.g amyloidosis and AD.

Answer 24

- Histological examination of affected tissues - Immunohistochemistry (visualize specific proteins or antigens in tissue sections using antibodies labeled with a detectable marker, such as an enzyme or fluorescent dye, to aid in the diagnosis and characterization of diseases) - sometimes genetic testing - identify specific proteins involved in amyloid deposits.

Answer 25

- can be caused by systemic conditions such as amyloidosis, where abnormal proteins (amyloids) accumulate in various organs including the kidneys.

Answer 26

can lead to renal dysfunction, proteinuria, nephrotic syndrome, and eventually progress to renal failure.

Answer 27

AA amyloid (associated with chronic inflammatory conditions), AL amyloid (derived from immunoglobulin light chains in plasma cell dyscrasias), and others.

Answer 28

typically through histological examination, immunohistochemistry, and molecular analysis- identifies specific proteins involved in amyloid deposition.

Answer 29

EVG: Histological staining technique used to visualize elastic fibers in tissues ( thickening of elastin layer) Congo read: Amyloid deposition in the kidney

Answer 30

Elastic layer: found in the tunica media of blood vessels, providing elasticity and recoil to the vessel walls. Tunica Media: middle layer composed of smooth muscle cells and elastic fibers, responsible for regulating vessel diameter and blood flow

Answer 31

- Conditions such as hypertension ( high bp) , atherosclerosis ( build-up of plaque in the arteries)

Answer 32

thickening reduces the flexibility and elasticity of the arterial walls-> decreased arterial compliance -> arteries become stiffer and less able to accommodate changes in blood pressure->can increase the workload on the heart and raise the risk of cardiovascular events such as heart attacks and strokes.

Answer 33

-refers to kidney tubules that have undergone a reduction in size or volume due to loss of cells and structural integrity. - occurs as a result of chronic kidney disease or other renal pathologies, leading to impaired kidney function.

Answer 34

refers to a kidney glomerulus that has become non-functional or inactive due to damage or degeneration. -occurs as a result of various pathological processes, such as chronic kidney disease, glomerulonephritis, or aging. - obsolete glomeruli may be replaced in some cases by scar tissue or fibrosis, leading to a loss of kidney function

Answer 35

- Uses heavy metal stains (e.g uranyl acetate and lead citrate) enhance contrast and visualise cellular structures at the nanometer scale - stains bind to certain cellular components highlighting them against the background and providing detailed images of subcellular structures

Answer 36

ShapeRed- Fenestrated Endothelium Yellow- GBM Green -Spiky layer, podocyte layer

Answer 37

- helps regulate filtration of waste products and substances from the blood into renal tubules while retaining essential proteins and blood cells

Answer 38

lead to various renal diseases, such as nephrotic syndrome and glomerulonephritis. Thin BM disease, leads to microscopic hematuria (blood in the urine) Thick BM due to high blood pressure.

Answer 39

PAS: shows Glomerular Basement Membrane (GBM), Glomerular Capillaries, Mesangial Matrix, Tubular Epithelial Cells IMF (Immunofluorescence) IgG: Uses fluorescent dyes emit fluorescent light, allows for visualization and detection of specific proteins within cells/tissues under fluorescence microscope. - IgG deposition on basememnt membrane showing thickening -Coarse granular deposition: indicative of mesangial cell deposits

Answer 40

Glomerulus – capillary loop with basement membrane which allows passage of specific molecules into the nephron Glomerulonephritis – inflammation/damage of the glomerular basement membrane resulting in altered function. Relatively uncommon cause of kidney injury Can present as nephrotic and/or nephritic syndrome

Answer 41

- Dysfunction / disruption of glomerular filtration barrier causing increased permeability , more proteins ( esp. albumin) into the urine, edema (swelling), and elevated blood cholesterol levels

Answer 42

Related to alterations in podocytes, endothelial cells and basement membrane of glomerulus rather than direct inflammation

Answer 43

- Not a disease, group of signs and symptoms: Massive proteinuria (excreting too much protein in urine) Proteinuria usually > 3.5g / 24hrs (>0.05g / kg / 24hrs in children) -Hypoalbuminemia Serum albumin < 30g/l -Oedema - Hyperlipidemia/ hyperlipiduria -Susceptibility to infections Unlike nephritic syndrome there is no haematuria

Answer 44

Diseases/ conditions originating within the organ/system affected

Answer 45

- Causes that arise as a result of another underlying condition or disease process. - Neprology: secondary glomeruluar disease occur as a complication of systemic diseases such as diabetes/lupus/infections.

Answer 46

Minimal change disease (MCD) Focal segmental glomerulosclerosis (FSGS) Membranous glomerulonephritis (MGN) Membranoproliferative glomerulonephritis (MPGN): is the inflammation of the glomeruli along with the deposit of antibodies in their membranes, which makes filtration difficult. Rapidly progressive glomerulonephritis - these diseases are characterised by specific patterns of injury to kidney filtering units

Answer 47

Diabetic nephropathy Systemic lupus erythematosus (multiorgan autoimmune disease) Sarcoidosis Sarcoidosis is a systemic inflammatory disease characterized by the formation of granulomas (small, often microscopic, nodular collections of immune cells) in various organs, particularly the lungs and lymph nodes. Hepatitis B Amyloidosis

Answer 48

- medical condition or disease that affects the entire body or multiple organ systems rather than being localized to a specific area or organ.

Answer 49

-swelling around the eyes and in the feet and ankles -foamy urine - weight gain due to excess fluid retention.

Answer 50

- Obtain complete medical history - Series of tests - Blood tests and clinical picture (overall presentation of signs, symptoms, and findings associated with a particular medical condition or disease) - Histology needed to confirm - diagnosis is based on the underlying cause

Answer 51

H&E: Exhibits diffuse glomerular changes (alterations or abnormalities that affect the majority or all of the glomeruli) within the kidneys. special stains like immunofluorescence (IMF) reveals protein accumulation in nephrotic syndrome.

Answer 52

types of nephrotic syndromes characterised by: -specific patterns of injusry to kidney glomeruli -leading to poteinuria - potneital progression to chronic kindey disease

Answer 53

Urine test To check the abnormalities in the urine. Blood test To determine levels of protein albumin. Kidney biopsy A small sample of kidney tissue for testing.

Answer 54

Foods to eat: Lean sources of proteins such as Lean meat Eating a low-salt diet Low in saturated fat and cholesterol diet Foods to avoid: Protein rich foods such as eggs and milk- can make nephrotic syndrome worse

Answer 55

Haematuria (presence of blood in the urine) Oliguria (reduced urine output) Azotemia elevated levels of nitrogenous waste products in the blood (Raised  blood urea nitrogen (BUN) and serum creatinine) Reduced GFR Fluid overload

Answer 56

impaired kidney function, leading to decreased filtration capacity and accumulation of fluid in the body, potentially resulting in edema, hypertension, and electrolyte imbalances. Thin glomerular basement membrane with pores that allow protein and blood into the tubule.

Answer 57

- Acute post-infectious glomerulnephritis

Answer 58

-IgA Nephropathy (Berger's disease) Primary glomerulonephritis characterized by deposition of IgA antibodies in the glomeruli. -Rapidly progressive glomerulonephritis (Severe form of glomerulonephritis marked by rapid decline in kidney function). -Proliferative glomerulonephritis Type of glomerulonephritis involving proliferation of cells within the glomeruli.

Answer 59

- Henoch-Schonlein purpura - a systemic vasculitis affecting small blood vessels. - Vasculitis - Inflammation of blood vessels - PSGN - Group A haemolytic streptococci of certain serotypes- important infectious causes associated with the development of nephritic syndrome.

Answer 60

H&E stain,: nephritic syndrome typically shows glomerular inflammation Special stains (e.g immunofluorescence (IMF)); differentiate immune complex deposition in nephritic syndrome Secondary nephritic syndromes may benefit from stains like Congo red to identify amyloid Thin glomerular basement membrane with pores that allow protein and blood into the tubule deposits.