Transcript Document

Pathology of Glomerular Disease II

Dr. Álvaro Barboza Quintana.

Clinico-pathologic Classification in Renal Syndromes H = High frequency among patients with the syndrome L = Low frequency among patients with the syndrome 1.

Nephrotic Syndrome (NS)Primary Nephrotic SyndromeMinimal change disease - H Focal segmental glomerulosclerosis - H Membranous glomerulopathy - L Systemic Nephrotic SyndromeDiabetes mellitus - H Amyloidosis - L Systemic lupus erythematosus (WHO Class V)

2A .

Nephritic Syndrome - Low Serum Complement Primary Nephritic Syndrome

•Post-infectious glomerulonephritis (GN) •Membranoproliferative GN -

L Systemic Nephritic Syndrome

•Systemic lupus erythematosus (WHO Class III, WHO Class IV) -

H

•Infectious endocarditis •HCV-associated cryoglobulinemia

2B. Nephritic Syndrome - Normal Serum Complement Primary Nephritic Syndrome

IgA Nephropathy

•Hereditary Nephritis (Alport syndrome) -

L

•Rapidly progressive GN (RPGN), ANCA associated, pauci immune

Systemic Nephritic Syndrome

Lupus nephritis (WHO Class II) H

•Anti-basement membrane disease (Goodpasture's Syndrome) •Systemic vasculitis: •Polyarteritis nodosa •microscopic polyarteritis •Wegener's granulomatosis •Henoch Schoenlein Purpura •Thrombotic thrombocytopenic purpura / Hemolytic uremic

L

syndrome

3 .

Acute Renal Failure

Pre Renal - Decreased renal perfusion

Renal

Rapidly progressive GN (RPGN)

•Pauci-immune RPGN, ANCA-associated •Anti-glomerular basement membrane disease (Goodpasture) -

L

•Immune complex mediated RPGN:Systemic lupus erythematosus, IgANephropathy, etc. •Acute tubulointerstitial diseases: •Acute tubular necrosis (ATN) -

H

•Acute interstitial nephritis (AIN) -

H

Post Renal - Obstruction 4 .

Chronic renal failure

Glomerular diseases that run with nephrotic syndrome

.

   

Minimal Change Disease (Lipoid Nephrosis)

Most frequent cause of nephrotic syndrome in children (2 – 6 years of age).

Follows a respiratory infection or routine prophylactic immunization.

“Its most characteristic feature is its usually dramatic response to corticosteroid therapy”

Etiology: It’s not known, in most cases is idophathic.

Interstitial nephritis by medical treatment

– –

HIV, heroin Hodgkin disease

Morphology MCD

   By light microscopy normal.

the glomeruli are By electron microscopy , the basement membrane appears normal.

Principal lesion : visceral epithelial cells show a uniform, and diffuse effacement of foot processes, – “Fusion” of foot processes, represents simplification of the epithelial cell architecture with flatening, retraction and swelling of foot processes.

Glomeruli are normal by light microscopy in minimal change disease, as shown in this biopsy. The glomerular basement membrane is thin and delicate, and mesangial cellularity and matrix are within normal limits. (Jones' silver stain, X200).

In this electron micrograph, overlying epithelial cell foot processes are effaced (giving the appearance of fusion) and run together.

Morphology MCD

   This changes are reversible after corticosteroid therapy and remission of the proteinuria.

The cells of the proximal tubules are often laden with lipid, reflecting tubular reabsorotion of lipoproteins passing through diseased glomeruli: Lipoid nephrosis .

Immunofluorescence show no immunoglobulin or complement deposits.

studies

Clinical Course

 Nephrotic syndrome: – Proteinuria (albumin) > 3.5 g/day.

– Hipoalbuminemia – Edema – Hyperlipidemia – Lipiduria – Thromboembolic events – Slow decrease of the glomerular filtrate

Membranoproliferative Glomerulonephritis (Mesangiocapillary glomerulonephritis )    5% to 10% of cases of idiopathic nephrotic sd. In children and young adults (< 30 years).

Associated with other systemic disorders and known etiologic agents (secundary MPGN) or may be primary, without known cause (idiopathic) in the kidney.

Primary MPGN – Type I: Inmune complexes and activation of alternative and classic pathways of complement – Type II:Alternative pathway of complement. Autoantibodies IgG (Nephritic factor C3) which joins with C3 convertase and inactivate C3.

Morphology MPGN

By light microscopy , both types are similar.

The glomeruli are large and hipercelular (by

proliferation of cells in the mesangium).

The glomeruli have an “hyperlobular” appearance

accentuated by the proliferating mesangial cells and increased mesangial matrix.

The GBM is thickened in the peripheral capillary

loops.

The glomerular capillary wall aften shows a

“double-contour” or “tram-track” appearance ( silver or PAS stains).

As seen here, the glomerulus has increased overall cellularity, mainly mesangial.

Extensive double contours of the glomerular basement membranes, stained by silver, in membranoproliferative glomerulonephritis type 1, caused by mesangial interposition and new basement membrane formation in response to subendothelial immune complex deposits. The deposits are PAS positive and globular-to-sausage shaped (Jones' silver stain; original magnification, x400).

Type I MPGN

 2/3 of cases  “Subendothelial electrodense deposits” under transmission electronic mycroscopy.

 Immnunofluorescence – C3 in a granular pattern – IgG – Early complement components (C1q and C4).

Membranoproliferative glomerulonephritis type 1. The marked endocapillary proliferation (proliferating endothelial and mesangial cells) appears to occlude the capillary lumen. Numerous large subendothelial and occasional mesangial-dense immune complex-type deposits (bottom middle) are present (transmission electron microscopy; original magnification, x4,700

Segmental, coarsely granular-to-globular or elongated capillary wall IgG deposits in membranoproliferative glomerulonephritis type 1 (immunofluorescence with anti-IgG; origina magnification, x200).

This electron micrograph demonstrates the dense deposits in the basement membrane of MPGN type II. There are dark electron dense deposits within the basement membrane that often coalesce to form a ribbon-like mass of deposits.

Type I

 Clinical Course: Massive proteinuria, Nephrotic sd.

 Treatment: Elimination of the infection.

 Prognosis : Good, 70 – 85% without clinical alterations.

Type II

Clinical Course: Nephrotic and Nephritic sd.Prognosis: Most patients progress to end-

stage renal disease within 10 years.

In both types: Hipocomplementemia, cause of the comsumption in the glomeruli.

Membranous Glomerulonephritis

Membranous Nephropathy Epimembranous GN Spikes GN

Membranous GN

 Most common cause of nephrotic syndrome in adults.  Characterized by: – Diffuse thickening of glomerular capillary wall – Accumulation of electron-dense, deposits of immunoglobulin. – Along the subepithelial side of the basement membrane

Membranous GN

 Idiopathic – 85% of cases  Secondary to: – Drugs: penicillamine, captopril, gold, NSAIDs – Underlying malignant tumors: carcinoma of lung, colon and melanoma. – Systemic Lupus: Most common type.

– Infections: chronic hepatitis B/C, syphilis, schistosomiasis, malaria. – DM, thyroiditis.

•Early Stage: Glomeruli appear normal or exhibit uniform, diffuse thickening of glomerular capillary wall.

•BM material is laid down between the deposits, appearing as irregular spikes protruding from the GBM (silver stain is the best)

IMMUNOFLUORESCENCE: Deposits of immunoglobulines (G or M) and complement.

Electron microscopy: thickening by irregular dense deposits between BM and podocites (subepithelial). Podocites have lost their foot processes.

Clinical Course

    Nephrotic syndrome or non-selective proteinuria. Common symptoms: hematuria, hypertension, and symptoms of secondary causes. Course: irregular, indolent. As the glomeruli sclerosis progresses: BUN elevated, hypertension and reduction in severity of proteinuria.

Prognosis and Treatment

 Prognosis: – 60% recovers with persistent proteinuria – 10% die or progress to renal insufficiency. – Spontaneous remission and better prognosis in women with non-nephrotic proteinuria.  Treatment: – NON

Renal Amyloidosis

Amyloidosis

    A systemic immune disease characterized by deposition of amyloid (may be localized) Amyloid is clinical settings.

a pathologic proteinaceous substance, deposited between cells in various organs and tissues with a wide variety of Tipically involves: – Kidneys, spleen, liver, myocardium, adrenals, thyroid, pituitary and tongue.

Associated with:multiple myeloma, chronic inflammatory conditions, chronic renal failure, Alzheimer’s disease, type 2 diabetes.

Amyloidosis

  Amyloid is formed by fibril proteins in 95% and by glycloproteins (P component) in 5%.

There are 15 biochemically distinct forms of amyloid proteins: – Amyloid Light Chain – Amyloid –associated protein – A b amyloid in Alzheimer’s disease – All produce the same consequences and give the same pattern in microscopy.

Renal amyloidosis is the most common and potentially the most serious form of organ involvevement.

Gross Pathology

Kidneys may be either : (1)Enlarged, firm with a waxy appearance (2)Shrunken and contracted owing to vascular stenosis.

S T A G E E A R L Y

Amyloid is deposited in the glomeruli, interstitium, arteries and arterioles. Appear as irregular thickenings of mesangium and capillary basement membranes.

Congo Red Stain - Polarizing microscopy Show diffuse amyloid deposition (green birefringence) in glomerular tufts and mesangial regions.

END STAGE: Glomerular tufts are flooded and replaced by masses or ribbons of amyloid.

Glomerular diseases that run with Nephrytitc Syndrome

Poststreptococcal Glomerulonephritis (Postinfectious Acute Glomerulonephritis)

Pathogenesis

Secondary to a pharyngeal infección with varying latent period

Nephritic syndrome

Group A (1,2,3,4,12,18,25,49,55,57,60)

Low complement levels, and high titles of streptococcal products.

Glomeruli

Granular immune depositsEndostreptsin and cationic antigens in afected áreas

Macro

Macroscopic hematuria with a rusty or smokey hue.

Micro

  

Glomeruli: bloodless, hypercelular and enlarged.

Proliferating mesangial and endothelial cells oclude the capillary lumina

PMN and monocyte infiltration.

Exudative and difuse (will affect all the lobules) Interstitium: edema

Electron Microscopy

Dome-shaped deposits projecting outward from epithelial side of basement membreane.

Epithelial cell slit poresSeparated from the basement

membrane by cearl zone continuos with the lamina rara externa.

PMN and monocytes

Clinical Features

Spontaneous nefritic syndrome

Fever, nausea, gross hematuria, oliguria after

recovery from pharyngitis.

Note: adults have a less spontaneous start with HTA.

During epidemics, symptoms may be rare.

1% of children develop intense oliguria and progresive glomerulonephritis.

Outcome in adults is less favorable.

During sporadic cases, 60% have an early recovery.

1 or more weeks.

Glomeruli show diffuse hypercellularity due to mesangial and endothelial cell increase and a large number of polymorphonuclear neutrophils (PMNs). H&E

Diffuse proliferative acute postinfectious glomerulonephritis with numerous PMNs with PAS-positive cytoplasm and endocapillary proliferation. PAS

The garland pattern of immune complexes due to large subepithelial deposits in acute postinfectious glomerulonephritis is shown (immunofluorescence

Hump-shaped deposits in acute postinfectious glomerulonephritis with extensive foot process effacement and endocapillary proliferation

Rapidly Progressive Glomerulonephritis

Rapidly Progressive Glomerulonephritis

General Info

 Very uncommon – 2 % of all cases presenting with GN  Predominates in men (2:1) – Young to middle aged

Rapidly Progressive Glomerulonephritis

Classification

1.- Post-infectious (Post-Streptococcal)

2.- Associated to Systemic Diseases

 Lupus, Goodpasture syndrome, vasculitis, Wegener 

3.- Primary or idiopathic

In all cases the basic pathogenic mechanism is immunogenic

Rapidly Progressive Glomerulonephritis

Pathogenesis

 The presence of fibrin in Bowman’s space promotes the epithelial proliferation and formation of crescents

GLOMERULUS

Extravasation due to capillary damage Fibrin Production stimulated by factors liberated by Monocytes Fibrin

Rapidly Progressive Glomerulonephritis

Microscopic and Macroscopic Aspect

  MACRO : pale hipertrophic kidneys with petechial hemorrages on the cortical surface MICRO : proliferation of glomerular epithelial cells and mononuclear infiltrate forming crescents in the urinary space (Neutrophils and linfocytes may also be found)

Crescents

: complex mixture of proliferating epithelial cells and infiltrating monocytes forming concentric layers around the capillary tufts (which are compressed) 

This is a case of RPGN due to Lupus

IDIOPATHIC RPGN

The implication of a cellular crescent is that the glomerulus has sustained

acute intense injury

.

Rapidly Progressive Glomerulonephritis

Pathogenesis of symptoms

Glomerular tufts adhere to Bowman’s capsule

OLIGURIA

Cicatrization of capillaries POST-GLOMERULAR ISCHEMIA

Renal Failure TUBULAR ATROPHY AND INTERSTITIAL FIBROSIS

Electron Microscopy: damage to basal membrane with ruptures but no evidence of immune complex deposition. •The urinary space in the top of the photograph shows portion of a crescent with the dark strands representing

fibrin

(arrow).

Immunofluorescence

: positivity with antibody to

fibrinogen

. With a rapidly progressive GN, the glomerular damage is so severe that fibrinogen leaks into Bowman's space, leading to proliferation of the epithelial cells and formation of a crescent.

Rapidly Progressive Glomerulonephritis

Clinical features

 

Extremely rapid deterioration of renal function, within weeks or up to 2 months

– Acute nephritis (Nephritic Sd.) with acute renal failure – Hypertension and edema – Hematuria, proteinuria, pyuria (nephrotic sd.) – Oliguria or anuria The patient may refer a viral syndrome or respiratory infection weeks before onset of renal failure

Goodpasture’s Syndrome (Anti-Basement Membrane Disease)

Goodpasture’s Syndrome 

General Info

Acute and necrotizing RPGN associated to pulmonary hemorraging and hemoptysis  Uncommon disease affecting primarily men (4:1) between 20-30 years of age.  Autoimmune disease in which there is production of Anti-Basement Membrane Antibodies (ABM) that deposit on alveoli and glomeruli

    Goodpasture’s Syndrome

Pathogenesis

The Goodpasture antigen resides in the non collagen portion of the 3-alpha chain of

type IV collagen

Precipitation factor is unknown, may be: – Virus – – – – Hydrocarbonated solvents Tobacco smoke (permissive role) Drugs Cancer Genetic predisposition: DRW15/DQW6 The lesion consists of deposits of ABM antibody and complement on the basement membrane of glomeruli and alveoli causing their destruction

   Goodpasture’s Syndrome

Macroscopic and Microscopic Aspect

MACRO

: same aspect as RPGN

MICRO

– : crescents composed of epithelial cells and monocytes surrounding capillary tufts in the urinary space – Methenamine silver stain

Electron Microscopy

: does not show deposits, only architectural damage and epithelial proliferation –

Immunofluorescence

The lungs show alveolar hemorrage, hemosiderin filled macrophages and thickening of alveolar septi. The BM shows immune deposits

Silver stain

Immunofluorescence

: shows positivity with antibody to

IgG

has a

smooth, diffuse, linear

pattern that is PATOGNOMONIC

     Goodpasture’s Syndrome

Clinical features

Typically begins as flu-like illness with evidence of pulmonary compromise Pulmonary hemorrages HEMOPTYSIS Progressive dyspnea Nephritis (Nephritic Sd.) and acute renal failure The disease progresses rapidly with renal failure ocurring within weeks or months

Treatment and Prognosis

   High doses of steroids, with or without cytotoxic agents.

Plasmapheresis removes ABM-antibodies Better prognosis than other diseases causing RPGN

Glomerulonephritis IgA or Of Berger

Classification

 This form of glomerulonephritis is characterized by the presence of prominent IgA deposits in the mesangial regions.

 Primary glomerular disease  Frequent cause of recurrent hematuria  Most common  Present in children and young adults.

Pathogenesis

   Genetic or acquired abnormality of inmune regulation leading to increased mucosal IgA synthesis in response to respiratory or GI exposure to environmental agents. IgA1 and IgA1complexes are entrapped in the mesanguim.

They activate the alternative complement pathway and initiate glomerular injury.

MICRO/ H&E

    Mesangial widening or proliferation (arrow) Segmental proliferation Overt crescentic glomerulonephritis (rare) Sclerosis (healing of focal proliferative lesion).

MICRO/ Electron Mic.

 Mesangial electron dense deposits and increased mesangial matrix and cellularity in IgA nephropathy (transmission electron microscopy, original magnification x8,500).

MICRO/ Immunofluorescence

 Mesangial deposition of IgA

Clinical Course

 Gross hematuria after GI or respiratory infection.

 5-10% develop a typical acute nephritic syndrome.

 Hematuria lasts several days and then subsides, only to return every few months.

Sistemic Lupus Erithematous Diffuse Proliverative Glomerulonephritis

Introduction

 SLE Classic prototype of the multisystem disease of autoimmune origin, characterized by a bewildering array of autoantibodies, particulary antinuclear antibodies (ANAs). Acute or insidious in its onset, it is a chronic, remitting and relapsing, often febrile illness characterized principally by injury to the skin, joints, kidney, and serosal membranes.

Classification Lupus Glomerulonephritis

Kidney appears to be involved in 60 to 70% of cases.

According to the WHO (morphologic class.)  Class I: Normal by light, electron, and imunofluorescent microscopy     Class II: Mesangial lupus glomerulonephritis Class III: focal proliferative glomerulonephritis Class IV: Diffuse proliferative glomerulonephritis Class V: Membranous glomerulonephritis

MICRO/ H&E

  

Proliferation of mesangial cells and endothelial cells, along with infiltrating mononuclear and polymorphonuclear leukocytes afecting more than 50% of the glomerular area.

Extensive peripheral capillary wall subendothelial immune deposition crescents.

(wire loop) , and extracapillary proliferation in the form of Fibrinoid necrosis, leukocyte infiltration, wire loop deposits, hyaline thrombi, and hematoxylin bodies

MICRO/ Others

Half of the tuft is distorted by marked endocapillary proliferation with occasional infiltrating cells. Segmental areas of basement membrane splitting and eosinophilic subendothelial deposits and mesangial eosinophilic deposits are visualized (Jones' silver stain; original magnification x400).

Clinical Course

 Typically have: – high anti-DNA antibody titers – low serum complement levels – Very active urinary sediment with:  erythrocytes  other casts present on urinalysis – Proteinuria – Half of the patients will have nephrotic syndrome – Hypertension

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