Amyloidosis

Amyloidosis of the kidney

Disease LM EM IF

Membranous GN Thickened GBM Subepithelial Deposits

Granular fl.of GBM

MPGN

Minimal change

Focal and

Seg.GS

Focal GN

Lupus Nephritis

Amyloidosis

DM

Chronic GNDef: it is end stage renal glomerular disease.

Grossly:-Small contracted kidney.-Granular outer surface.-Firmly adherent capsule.-Loss of differentiation bet. cortex and medulla.-Thick BVs at corticomedullary junction.

Chronic GN: Note contracted kidney& granular outer surface

Msc:

Glomeruli: -Hyalinised and sclerotic.-Some are hypertrophied.

Tubules are atrophied and

dilated

Interstitial fibrosis and

chronic inflammatory cell

infiltration

Thick walle-blood vessels end arteritis obliterans

Chronic glomerulonephritis

Hyaline cast

Chronic GN

Clinical and laboratory Findings:

Marked hypertension

IncreaseBl. urea

Urine changes-Polyuria.- low Specific gra.-Mild albuminuria.-Hyaline and -granular casts

Prognosis: without Treatment is poor

Small- Sized Kidney (contracted kidney)

1-Hypoplastic kidney.

2-Chronic GN

3-Chronic PN

4-Senile(atherosclerotic) kidney.

5-Kidney of benign hypertension (Benign nephrosclerosis).

DMEffects of DM on the kidney:-Diabetic GS-Renal arteriolar sclerosis.-pyelonephritis.-papillary necrosis.

Diabetic GSIt leads to:a-Proteinuria.B-Nephrotic syndrome.C-CRF.

MSC: 1-Diffuse GS.-Diffuse increase in mesangial matrix-Thickening of GBM2-Nodular GS. (kimmelsteil Wilson disease)Hyaline nodule is present in the mesangium,Containing fibrin and lipid.

3-Insudative lesion:-fibrin cap; eosinophilic focal Thickening of peripheral capillary loop.-Capsular drop: eosinophilic thickening of Bowman’s capsule

Diffuse glomeruosclerosis

Nodular GS

Nodular GS

Fibrin cap and Capsular drop

Lupus nephritis

Presentation: Recurrent hematuria,nephritic s,nephrotic s,hypertension,CRF.

Classification;-class I:Normal kidney.-Class II:Mesangial glomerular lesion.-Class III:Focal proliferaive GN.-Class IV:Diffuse Proliferative GN.-Class V:Membranous GN.-Class VI:Advancing sclerosing GN.

MSC of Class IV: Diffuse Proliferative GN

-Diffuse hypercellularity due to Proliferation of endothelial cells and mesangial cells -Irregular thickening of GBM - Wire loop appearance-Few epith.crescents-Hematoxylin bodies.

Proliferative lupus nephritisFlea-Bitten appearance

Class II: Mesangial GN

Class III: Focal GN

Focal and segmental necrosis of glomerulus

Class IV:Diffuse Proliferaive GN

Hematoxylin bodies Wire-Loop appearance

IF of Lupus Nephritis

EM of Lupus Nephritis

• IF: Granular fluorescence of capillary walls for Igs and comploments

• EM: Subendothelial and mesangial electron dense deposits

Tubulointerstitial nephritisDef: diseases affecting tubules and interstitial tissues of the kidney.

1-Pyelonephritis

Pelvis of the kidney is commonly involved in bacterial infection,hence pyeloCause: bacterial infection as E-coli ,B. proteus, B. pyocyaneus and others

PF: -obstruction. -Vesicoureteric reflux-Instrumentation. -Female sex.-Pregnancy. -DM.-Bilhaziasis.

Routes of infection

-Ascending Lymphatic from GIT

HematogenousFrom boil

Acute PN

Grossly:-Enlarged kidney. -Congested PCS-Yellow streaks from papillae to cortex.

Acute PN

Yellow foci of pus

Acute pyelonephritis

Chronic PNCharacterized by:-Interstitial inflammation and scarring-Deformity andscarring of pelvicalyceal system

Gross-Small sized kidney (contracted).-Irregular outer surface due to retraction of the capsule.-Distorted pelvicalceal system .

Chronic pyelonephritis

Chronic PN

Microscopic:

-Periglomerular fibrosis -Dilated tubules containing hyaline casts (thyrodization)-Thick walled BVs-Interstitial fibrosis and chronic inflammatory cell infiltration.

Microscopic of Ch.PN

Chronic PN. Note periglomerular fibrosis

Ch. PN. Thyrodization

Complication

-Secondary hypertension.-proteinuria.-Chronic renal failure.

Other types of renal infection

-Pyaemia-Tuberculosis.

2-Drug-induced interstitial nephritisMechanisms:1-immunologic reaction or hypersensitivity reaction type I Acute interstitial nephritis e.g rifampicin, penicellin,thiazides

2-Slow damage to tubules Chronic interstitial nephritis via type IV reaction e.g. Analgesic nephropathy

3-Direct nephrotoxicity ATN

Drug induced interstitial nephritis

Chronic tubulointerstitial nephritis

3-Acute tubular necrosis

Def: destruction of tubular epithelial cells with acute suppression of kidney function. It is reversible renal lesion.

Types

Anoxic(ischemic) ATN:-Mismatched biood trasfusion-Shock &severe hypotension-Severe trauma

Toxic ATN-poisons as Mgcl,CCl4,Phosphorus,&insecticides-Drugs e.g. gentam,amphotricin B

Acute tubular necrosis

Acute tubular necrosis

Vascular diseases of the kidney

1-Renal artery stenosisCause:-Atheromatous plaque. -Fibromuscular dysplasia.Effects: secondary hypertension(2-5%),due to renin production.

2-InfarctsPresented by painless hematuria.Causes:-Embolism -Thrombosis on top AS

Atheromatous plaque

Thrombosed renal artery

Infarct of the Kidney

Infact kidney

Infarction of The kidney

3-Senile atherosclerotic kidneyGrossly:-Both kidneys are reduced in size.-The outer surfaces show depressions due to scarring-The renal artery is atheromatous.

MSC:-Wedge-shaped areas of fibrosis.-Hyalinized glomeruli.- Tubules.are replaced by fibrous tissue

Atherosc.of the aorta and kidneys

Aortic Aneurysm with thrombus and senile kidneys

Atherosclerotic kidney

Atherosclerotic renal artery

Atheromatous plaque

4-Hypertension

A-Benign nephrosclerosis

Grossly;-Both kidneys are reduced in size (contracted)-Granular outer surface-Loss of demarcation between cortex and medulla

Microscopic;-Hyaline arteriolosclerosis-Fibroelastic hyperplasia of large arteries-Diffuse ischemic atrophy of the nephron

B. Nephrosclerosis

Arteiolosclerotic kidney

Arteriolonephrosclerosis

Benign nephrosclerosis

Benign Nephrosclerosis

B-Malignant nephrosclerosis

Grossly:-Enlarged kidney with peticheal he

Microscopic:-Fibrinoid necrosis-Smooth muscle proliferation and duplication of basementmembrane ( onion-skin appearance)-Necrotizing glomerulitis

Fibrinoid necrosis in malignant hypertension

Malig. Nephrosclerosis. Onion –skin appearance

5-Bilateral cortical necrosisRare lesionCause; ischemic as in toxemia of pregnancy or severe infections such as pneumonias and diphtheriasGross; yellow cortex of both kidneysMSC: Coagulative necrosis

6-Necrosis of renal papillaeRare lesionCause :ischemic necrosis due to PN, with DM, excess phenacetin and chronic alcoholism

Cortical necrosis

Necrosis of renal papillae

Necrotizing papillitis

Necrosis of renal papillae