1. The Kidney & Collecting System  Diseases of Tubules & Interstitium: 1. Infectious:  Acute Pyelonephritis  Chronic Pyelonephriris 2. Non-infectious:  Drug-Induce Interstitial Nephritis Allergic Analgesic  Acute Tubular Necrosis

2. Acute Pyelonephritis Gross: One /or both Kidneys involved Normal or/enlarged Microabscesses in both cortex and medulla (hematogenous)

3. n Glomeruli Not involved n Suppurative inflammation (Abscess) –Interstitium: Neutrophils infiltrate –Tubules (WBCs Casts) Acute Pyelonephritis

4. The Kidney & Collecting System  Diseases of Tubules & Interstitium: 1. Infectious:  Acute Pyelonephritis  Chronic Pyelonephriris 2. Non-infectious:  Drug-Induce Interstitial Nephritis Allergic Analgesic  Acute Tubular Necrosis

5. Chronic Pyelonephritis & Reflux Nephropathy n Interstitial inflammation & Scarring of Renal Parenchyma n Gross Scarring & Deformity of Pelvicalyceal System n Important cause of Chronic Renal Failure

6. Chronic Pyelonephritis Morphology:

7. The Kidney & Collecting System  Diseases of Tubules & Interstitium: 1. Infectious:  Acute Pyelonephritis  Chronic Pyelonephriris 2. Non-infectious:  Drug-Induce Interstitial Nephritis Allergic Analgesic  Acute Tubular Necrosis

8. Drug-induced Interstitial Nephritis ARF 1. Acute drug-induced Interstitial Nephritis  ARF CRF 2. Analgesic Nephropathy  CRF

9. 1) Acute drug-induced Interstitial Nephritis Morphology:

10. 2) Analgesic Nephropathy Drugs: “Combinations” of “large quantities” for “long periods” n Phenacetin n Aspirin n Acetaminophen n Caffeine n Codeine Leading to  Renal Papillary Necrosis & Interstitial Nephritis

11. The Kidney & Collecting System  Diseases of Tubules & Interstitium: 1. Infectious:  Acute Pyelonephritis  Chronic Pyelonephriris 2. Non-infectious:  Drug-Induce Interstitial Nephritis Allergic Analgesic  Acute Tubular Necrosis

12. Acute Tubular Necrosis (ATN) n Clinico-Pathological entity Characterized by:  Destruction of tubular epithelial cells  Acute Renal Failure n The most common cause of acute renal failure n Reversible renal lesions

13. Cont. Acute Tubular Necrosis (ATN) Morphology: