The document discusses different types of kidney diseases and disorders: - It describes the normal anatomy and histology of the kidney, including structures like the glomerulus. - Nephrotic syndrome is discussed, which is characterized by proteinuria and low albumin levels, causing fluid retention and edema. Investigations include urine tests and kidney biopsies. - Different glomerular diseases are described based on their pathology, including membranous glomerulonephritis, minimal change disease, focal segmental glomerulosclerosis (FSGS), and membranoproliferative glomerulonephritis. Their features on light microscopy, immunofluorescence and electron microscopy are provided. - IgA nep

1. By: Hamza AlGhamdi

2. NORMAL KIDNEY’S PHYSIOLOGY AND HISTOLOGY

3. Capillary Space Endothelium Urinary Space GBM Podocyte

4. NORMAL KIDNEY HISTOLOGY

5. Parietal Epithelium Visceral Epithelium Capillary Lumen Mesangial Cell Basement Membrane (GBM) Urinary Space RBC Endothelial Cell

6. NEPHROTIC SYNDROME IS NOT A DISEASE

7. Fluid retention -> abdominal distention , ascites , edema , puffy eyelids ,scrotal swelling , weight gain , shortness of breath Anorexia Hypertension Oliguria Orthostatic hypertension Skin striae Foamy urine

8. Periorbital edema Pitting edema of lower limbs

9. INVESTIGATIONS Urine sample shows proteinuria (>3.5/day ) It is also examined for urinary casts Comprehensive metabolic panel (CMP) shows Hypoalbuminemia High levels of cholesterol (hypercholesterolemia), specifically elevated LDL Electrolytes, urea and creatinine (EUCs): to evaluate renal function Biopsy of kidney Auto-immune markers

10. Excessive permeability of plasma proteins - >> heavy proteinuria Depletion of plasma proteins , mainly albumin - hypoalbuminaemia

11. Liver compensates but not successful - >> reversed A:G ratio Reduced albumin -> decreased colloid oncotic pressure of the blood -> oedema

12. ADH is stimulated - >> oedema Increased Lipoprotein synthesis and decreased catabolism by liver ->> Hyperlipidaemia (mainly VLDL and /or LDL) HDL is also lost in urine when heavy proteinuria occurs

13. Loss of body proteins (immunoglobulins /complement) -> frequent infection Loss of anticoagulants antithrombin III , antiplasmin - > thrombotic and embolic phenomenon

16. Major cause of NS in adults Characterised by presence of electron-dense immune deposits along the epithelial side of GBM (subepithelial ) Idiopathic in 85% of patients The 15% remaining GN is associated with malignant tumors , SLE , drugs , infections or metabolic disorders

18. Membranous GN Sub-epithelial immune Complex deposits Thickened GBM

19. Membranous GN H&E

20. Membranous GN IF

21. Capillary Lumen GBM GBM Membranous GN EM

22. MINIMAL CHANGE DISEASE the major cause of nephritic syndrome in Children normal glomeruli on light Microscopy uniform and diffuse effacement of the foot Processes of visceral epithelial cells on electron microscopy Immunofluorescence shows no immune deposits The cause and pathogenesis are unknown dramatic response to corticosteroid therapy. long-term prognosis is excellent.

24. MINIMAL CHANGE DISEASE Foot Process Fusion

27. sclerosis of some, but not all, glomeruli (thus, it is focal) FSG can be. * Idiopathic. * A secondary evernt, refecting glomerular scarring, consequent to another primary glomerular disease (e.g., IgA nephropathy). * associated to other known disorders (e.g. heroin abuse, HIV infection, obesity). * The result of inherited mutations of proteins present in podocytes (podocin, a –actinin) or in the slit diaphragm between podocytes (nephrin).

28. 1- Light Microscopy: Normal and diseased glomeruli (Focal) Segmental tuft sclerosis in diseased glomeruli 2- Immunofluorescence No deposits Deposits of IgM and C3 3- EM: Focal fusion of foot processes Glomerular fibrosis

29. FSGS H&E

30. MEMBRANOPROLIFERATIVE GLOMERULONEPHRITIS Thickness of capillary loops and glomerular cell proliferation Glomeruli have a lobular appearance because of mesangial proliferation Capillary walls often have a double-counter or tram-track appearance

31. MEMBRANOPROLIFERATIVE GLOMERULONEPHRITIS Type 1 has subendothelial electron-dense deposits of immunoglobulins and complements It occurs in patients with SLE , hepatitis B and other diseases Type 2 has electron-dense GBM deposition in a confluent ribbon-like fashion Type 2 is due to activation of alternative pathway of complement activation

32. Figure 8. Pathology of membranoproliferative glomerulonephritis type I. (a) Light microscopy shows a hypercellular glomerulus with accentuated lobular architecture and a small cellular crescent (methenamine silver).

33. IGA NEPHROPATHY (BERGER DISEASE) the most common type of glomerulonephritis worldwide major cause of recurrent glomerular hematuria By light microscope, the glomeruli can appear nearly normal, showing only subtle mesangial hyprcellularity, or can reveal focal proliferative or sclerotic lesions The pathogenesis is nuclear although a genetic or acquired defect in immune regulation leading to increased mucosal IgA secretion. There isalso decreased clearance of IgA complexes by the liver.

34. Similar IgA deposits are seen in Henoch-Schönlein purpura in children hematuria typically lasts for several days chronic renal failure develops in 50% over a period of 20 years

35. THANK YOU Powerpoint presentation