2nd lecture kidney special Pathology.pptx

specialist Pathology renal lecture

1. Acute Poststreptococcal glomerulonephritis (Acute proliferative GN, Postinfectious GN) Immune complexes Clinical features: Children >> adults Occur 2-4 weeks after streptococcal infection of the skin and throat Organism: Group A β -hemolytic streptococci May be caused by other bacteria , viruses, parasites, SLE, PAN 1

2. Lab studies Elevated antistreptolysin O (ASO) titers Low serum complement (C3) 2

3. Strep Pharyngitis 3

4. Morphology Light microscopy: Hypercellular glomeruli with neutrophils and monocytes Immunoflorescence (IF): Granular deposits of IgG, IgM and C3 throughout the glomerulus Electron microscopy: Subepithelial humps immune complex deposits 4

5. Morphology (Light microscopy) 5

6. Morphology (EM and IF) 6

7. Localization of immune Complexes in Glomerulus 7

8. Treatment and Prognosis Treatment: Diuretics, Antibiotics! Prognosis: Children Complete recovery in 95% of cases RPGN (1%) Chronic glomerulonephritis (2%) Adults Complete recovery (60%) RPGN/CRD (40%) 8

9. Goodpasture Syndrome ( antiGBM Disease) Definition: production of antibodies directed against basement membrane ( antiGBM antibodies) which result in damage of lungs and kidneys The goodpasture antigen is type IV collagen 9

10. Clinical Features Males>females Peak incidence ages 20-40 y Pulmonary involvement typically precedes the renal disease Presents with pulmonary hemorrhage and recurrent hemoptysis (necrotizing hemorrhagic interstitial pneumonitis) Most develop RPGN Anti GBM antibodies in blood (initial test) 10

11. Morphology (in Kidney) Light microscopy: Hypercellularity , crescents , fibrin Immunoflorescence (IF): Smooth and linear pattern of IgG and C3 in glomerular basement membrane Electron microscopy: No deposits but there is GBM disruption 11

12. Immunoflorescence in Goodpasture Syndrome (Kidney) 12

13. Morphology in Lung Acute intra-alveolar hemorrhage Hemosiderin laden macrophages 13

14. Morphology of Goodpasture in Lung 14

15. Lungs and Kidney Involvement in Good Pasture syndrome 15

16. Treatment and prognosis Treatment: Plasma exchange, steroids, and cytotoxic drugs Prognosis: Poor Pulmonary hemorrhage may be severe and life threatening RPGN leading to renal failure Early aggressive treatment may prevent end stage renal disease 16

17. Sample MCQ (2009 annual) Which of the following is the most likely cause of the clinical combination of generalized edema, hypoalbuminemia, and hypercholesterolemia in an adult whose urinalysis demonstrated marked proteinuria with fatty casts and oval fat bodies? A) nephritic syndrome B) nephrotic syndrome C) acute renal failure D) renal tubular acidosis E) urinary tract infection 17

18. Sample SAQ (Supplementary 2012) Approximately 10 days after an episode of pharyngitis, an 8 y old girl suddenly becomes lethargic, febrile and nauseated. Her urine output is decreased and cola colored. Urinalysis shows mild proteinuria, hematuria, and RBC casts. ASO titer is raised A) what is the most likely diagnosis? B) give the immunofluorescence and electron microscopic findings of renal biopsy performed in such case C) give the clinical course of this disease 18

19. Sample MCQ A 24 y old man comes to the clinic because of recent onset hemoptysis. His tem is 98.6 oF , pulse 104/min, respirations are 18/ min and BP is 170/90 mmHg. PE reveals no other abnormality. Lab studies show Hemoglobin is 9.5 g/dL, leukocyte count 11,500, plt 200000, BUN 67, Cr 3.8 mg/dL, C3 135, C4 40, ANCA antibodies negative. ANA is also negative Urinalysis show RBC casts. CXR shows bilateral fluffy pulmonary infiltrates. Which of the following is the most likely diagnosis? A) good pasture syndrome B) Henoch schoenlin purpra C) postinfectious GN D) SLE E) wegeners granulomatosis 19