Pathology Of Tubulointerstitial Disease

Question 1

How is tubulointerstitial kidney disease differentiated clinically from glomerular diusease?

Answer 1

• Absence of nephrotic or nephritic syndrome

- presence of defects in tubular function

Question 2

Path features of BK polyoma virus

Answer 2

• renal tubules have intracellular viral nuclear inclusions

Question 3

Chronic Pyelonephritis types

Answer 3

Reflux: Infx of peripheral concave compound papillae in poles of the kidneys; from vesicoureteral reflux

Obstructive: High pressure leafs to infx and diffuse scarring/ thinning of cortex

Question 4

Acute interstitial Nephritis Path

Answer 4

• diffuse Interstitial edema + fibrosis
• thickened glom basement membrane
• N/0 infiltrate w/ unafected glomeruli

Question 5

Chronic interstitial nephritis path

Answer 5

• Interstitium expanded by fibrosis

- distortion of tubules + periglomerular fibrosis

Question 6

Urinary Cast findings in kidney disease

Answer 6

Acute Tubular injury: Dirty brown + epithelial cells

Glomerulonephritis: RBC cast + proteinuria

Tubulointersitial nephritis: WBCs + Pyuria

Question 7

Micro findings acute pyelonephritis

Answer 7

• WBC Casts
• Microabcess formation w/ renal parenchymal changes in interstitium + tubules
• tubular necrosis

Question 8

Complications of Pyonephritis

Answer 8

• Papillary necrosis
• Pyonephrosis
• Emphysematous pyelonphritis

Question 9

Microscopic changes chronic pyelonephritis

Answer 9

• tubulointerstiial nephritis
• Thyroidization -> tubular dilation + intraluminal eosinophilic hyaline casts looking similar to thyroid follicles
• Glomerular fibrosis/sclerosis

Question 10

Xanthogranulomatous pyelonephritis

• PAth
• Micro

Answer 10

• CPV variant
• Large, yellow-orange mass-like lesions
• Gram-neg organisms
• Confused w/ RCCA
• Micro: foamy M0 w/ lymphocytic infiltrate; vascularized granulation tissue, hemorrhage

Question 11

Analgesic Nephropathy

• Morph
• Histo

Answer 11

• Morph: Reduced kidney size; bumpy irregular contours; papillary calcifications
• Hist: Medullary injury w/ papillary necrosis -> atrohpy, chronic inflammation, + scarring

Question 12

Light chain cast nephropathy

• Eti
• Path
• LabDx

Answer 12

• Eti: Multiple Myeloma
• Path: Bence-Jones proteinuria + cast nephropathy -> epithelial toxicity + direct cast damage to nephrons
• LabDx: eosinophilic bright + glassy casts with fracture + angular borders in distal tubules + collecting ducts

Question 13

Urate nephropathy

Answer 13

• Golden streaks in medulla

- uric acid crystal deposition on frozen section