Glomerular Disease Etiologies

Nephritic Syndromes (Inflammatory)
- Poststreptococcal GN: Post-Group A Strep infection.
- IgA Nephropathy: Concurrent with mucosal infection (URI/GI).
- RPGN (Crescentic):
  - Anti-GBM (Goodpasture’s): Abs to collagen IV (kidneys + lungs).
  - Pauci-Immune: ANCA-associated vasculitis (GPA, MPA).
- Alport Syndrome: X-linked defect in Type IV collagen.
Nephrotic Syndromes (Podocyte Damage)
- Minimal Change Disease: Idiopathic (kids); Hodgkin lymphoma.
- FSGS: HIV, heroin use, obesity.
- Membranous Nephropathy: Anti-PLA2R Abs, solid tumors, HBV, NSAIDs.
- Diabetic Nephropathy: Longstanding diabetes mellitus.
- Amyloidosis: Multiple myeloma (AL), chronic inflammation (AA).
Mixed Nephritic-Nephrotic
- MPGN: HCV, cryoglobulinemia, C3 nephritic factor.
- Lupus Nephritis: SLE (DNA-anti-DNA immune complexes).

Tubular & Interstitial Disease Etiologies

Acute Tubular Necrosis (ATN):
- Ischemic: Shock, sepsis, hypoperfusion.
- Nephrotoxic: Aminoglycosides, contrast dye, rhabdomyolysis (myoglobin).
Acute Interstitial Nephritis (AIN):
- Drug hypersensitivity (NSAIDs, Penicillins, PPIs).
Renal Tubular Acidosis (RTA):
- Type 1 (Distal): Autoimmune (Sjögren), Amphotericin B.
- Type 2 (Proximal): Fanconi syndrome, Multiple Myeloma.
- Type 4 (Hyperkalemic): Diabetes, ACE inhibitors, ARBs, K⁺-sparing diuretics.