1. Acute Poststreptococcal Glomerulonephritis (APSGN)
PATHOPHYSIOLOGY
Acute Poststreptococcal Glomerulonephritis (APSGN)

2. PATHOPHYSIOLOGY Acute Nephritic Syndrome
glomerular syndrome characterized by acute onset of usually grossly visible hematuria, mild to moderate proteinuria and hypertension.
Two Types of Acute Nephritic Syndrome:
Acute Glomerulonephritis – the diagnosis of the patient
Rapidly Progressive (Crescentic) Glomerulonephritis

3. PATHOPHYSIOLOGY Acute Glomerulonephritis
characterized anatomically by inflammatory alterations in the glomeruli
Light microscopy – enlarged hypercellular glomeruli with leucocytic infiltration
IF – granular IgG and C3 in GBM and mesangium
EM – subepithelial humps
clinically by the syndrome of acute nephritis:
Hematuria
Red blood cell casts in the urine
Pyuria
Mild to moderate proteinuria
Hypertension
Edema

4. PATHOPHYSIOLOGY Two Types of Acute Glomerulonephritis:
Acute Proliferative/Poststreptococcal Glomerulonephritis
Non-Streptococcal Acute Glomerulonephritis
Bacterial infections
Viral disease
Parasitic Infections

5. PATHOPHYSIOLOGY DISEASE PROGRESSION Sore Throat and Severe Cough
After about 2 weeks  Cola – Colored Urine and Bipedal Edema
PE and Lab Workups: Clinical Signs of Nephritic Syndrome
Acute Poststreptococcal Glomerulonephritis

6. PATHOPHYSIOLOGY
Acute Poststreptococcal glomerulonephritis follows infection with only certain strains of streptococci designated as nephritogenic.
Group A Beta Hemolytic streptococci
Pyodermatitis with streptococci M types 47, 49, 55, 2, 60, and 57
APSGN develops 2-6 weeks
Throat infection with streptococci M types 1, 2, 4, 3, 25, 49, and 12
APSGN develops 1-3 weeks

7. PATHOPHYSIOLOGY ASPGN is an immune-mediated disease
immune complex containing a streptococcal antigen is deposited in the affected glomeruli
The 3 antigens isolated from nephritogenic streprococci are:
Cysteine protease streptococcal pyrogenic exotoxin B
Nephritis associated streptococcal plasmin receptor which is a plasmin-binding protein with glyceraldehyde phosphate dehydrogenase (also known as presorbing antigen or PA-Ag)
Streptokinase

8. PATHOPHYSIOLOGY
The size of glomerular basement membrane (GBM) pores and the molecular size of the streptococcus-Ig complex are also important determinants.
Streptococcus-Ig complex = 15 nm
10 nm = streptococcus group A
5 nm = immunoglobulin
Children = 2-3 nm
Adults = nm

9. PATHOPHYSIOLOGY Elevated titers of antibodies
Serum complements are low
Granular immune deposits in glomeruli and electron dense deposits
Rheumatoid factor
Cryoglobulins
Antineutrophil cytoplasmic serum antibodies
Host susceptibility factors (HLA-DRB1*03011)