1. Renal Pathology

Question 1

What are the congenital kidney anomalies?

5

Answer 1

1. Horseshoe kidney
2. Renal agenesis
3. Dysplastic kidney
4. Polycystic kidney disease (PKD)
5. Medullary cystic kidney disease

Question 2

Describe horseshoe kidney.

Answer 2

• Most common anomaly
• Conjoined kidney connected at lower pole
• Found in lower abdomen
• Get caught in inferior mesenteric artery during ascent from pelvis to abdomen

Question 3

What is renal agenesis?

Answer 3

• Absence of kidneys
• Can be unilateral or bilateral

UNILATERAL
- hypertrophy of existing kidney —> hyperfiltration and increases risk of renal failure later in life

BILATERAL
- oligohydramnios (low amniotic fluid) w/ lung hypoplasia, flat flace, low set ears, developmental defects of extremities

Question 4

What is dysplastic kidney?

Answer 4

• Non inherited malformation of renal parenchyma characterized by cysts and abnormal tissue
• Can be unilateral and bilateral
• If bilateral, make sure it is not inherited from polycystic kidney disease

Question 5

What is polycystic kidney disease?

Answer 5

• Inherited defect leading to bilateral enlarged (cystic) kidneys in renal cortex and medulla
• Can be AD or AR

AR

• Infants
• Worsening RF and hypertension
• Newborns born with Potter sequence (a/w congenital hepatic fibrosis = leading to portal hypertension) and hepatic cysts

AD

• Young adults
• Hypertension (b/c increased renin), hematuria, and worsening RF
• Due to mutation in APKD1 or APKD2 gene
• Cysts develop over time
• A/w berry aneurysm, hepatic cysts and mitral valve prolapse

Question 6

What is medullary cystic kidney disease?

Answer 6

• Inherited , AD
• Defect leading to cysts in the medullary collection ducts
• Parenchymal fibrosis = shrunken kidneys and worsening RF

Question 7

What is acute renal failure (ARF)?

What is the hallmark?
(1)

What are the causes?
(4)

Answer 7

• Acute, severe decrease in RF (develops within days)
• HALLMARK: azotemia (increased BUN and creatinine) with oliguira

CAUSES

1. Pre renal
2. Post renal
3. Intra renal
4. Acute tubular necrosis

Question 8

What is pre renal azotemia?

Answer 8

• Due to decreased blood flow to kidneys (CF)
• Decreased blood flow = decreased GFR, azotemia, oliguria
• Common cause of ARF

Question 9

What is post renal azotemia?

Answer 9

• Due to obstruction of urinary tract downstream from kidney (ureters)
• Decreased outflow results in decrease GFR, azotemia, oliguria

Question 10

What is acute tubular necrosis?

Answer 10

-

- Injury and necrosis of tubular epithelial cells