Anatomy and Disorders of the Kidney

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is a prominent feature of nephritic syndrome?

Metabolic acidosis

Hyperkalemia

Hematuria (correct)

Hypotension

Which of the following conditions is associated with acute diffuse proliferative glomerulonephritis?

Tuberculosis

Post-streptococcal infection (correct)

Urinary tract infection

Chronic kidney disease

What is primarily responsible for increasing blood pressure in nephritic syndrome?

Decreased glomerular filtration rate

Renal artery dilation

Increased production of renin (correct)

Increased sodium excretion

Which laboratory finding is typically elevated in nephritic syndrome?

Antistreptolysin O (ASO) antibodies Signup and view all the answers

What is the expected urine output in a patient with nephritic syndrome?

Oliguria Signup and view all the answers

What complication is commonly associated with nephritic syndrome?

Hypertension Signup and view all the answers

In nephritic syndrome, which symptom is most indicative of kidney inflammation?

Edema Signup and view all the answers

Which of the following best describes azotemia in nephritic syndrome?

Elevated blood nitrogenous waste Signup and view all the answers

What is a common site for metastasis of renal cell carcinoma?

Lungs Signup and view all the answers

Which symptom is most commonly associated with local spread of renal cell carcinoma?

Painless hematuria Signup and view all the answers

What primary condition leads to left-sided varicocele in left renal cell carcinoma?

Tumor invasion of the renal vein Signup and view all the answers

Which symptoms can result from paraneoplastic syndromes related to renal cell carcinoma?

Hypercalcemia Signup and view all the answers

What is the predominant age group for the occurrence of Wilms tumor?

Toddlers (1-3 years) Signup and view all the answers

Which histological component is characterized by small, round primitive cells in Wilms tumor?

Blastema Signup and view all the answers

What type of growth pattern is typically seen in Wilms tumor?

Rapidly growing and infiltrative Signup and view all the answers

What is the most common symptom due to distant metastases associated with renal cell carcinoma?

Bone fractures Signup and view all the answers

What is the most common variant of renal cell carcinoma?

Clear cell renal cell carcinoma Signup and view all the answers

Which histological feature is characteristic of clear cell renal cell carcinoma?

Compressed renal tissue pseudocapsule Signup and view all the answers

Which type of renal cell carcinoma has the best prognosis?

Chromophobe renal cell carcinoma Signup and view all the answers

Which of the following is a risk factor for developing renal cell carcinoma?

Genetic factors such as von Hippel-Lindau syndrome Signup and view all the answers

What is a primary characteristic of papillary renal cell carcinoma?

Branching papillae with a single layer of cells Signup and view all the answers

What histological arrangement is commonly seen in chromophobe renal cell carcinoma?

Compact growth pattern with a perinuclear halo Signup and view all the answers

Which type of renal cell carcinoma is typically multifocal and bilateral?

Papillary renal cell carcinoma Signup and view all the answers

In clear cell renal cell carcinoma, what primarily accounts for the clear appearance of the cytoplasm?

Presence of lipid and glycogen Signup and view all the answers

Study Notes

Anatomy of the Kidney

The nephron is the functional unit of the kidney, comprised of a renal corpuscle and a renal tubule.
The renal corpuscle contains a glomerulus, a network of capillaries inside Bowman's capsule, and a mesangium, which supports the glomerulus.

Nephritic Syndrome

A collection of signs and symptoms caused by kidney inflammation
Characterized by:
- Hematuria
- Mild to moderate proteinuria
- Oliguria: Reduced urine output
- Uremia: Elevated blood urea and creatinine levels
- Azotemia: Increased nitrogen-rich waste in the blood
- Edema: Often in the face or legs
- Hypertension

Acute Diffuse Proliferative Glomerulonephritis

Also known as post-streptococcal or acute glomerulonephritis
Follows upper respiratory tract infections caused by nephritogenic strains of group A beta-hemolytic streptococci
Immune complexes of antibodies against the bacteria deposit in the glomeruli, causing inflammation.
Inflammation leads to endothelial cell proliferation, narrowing the capillary lumen, reducing blood flow and glomerular filtration rate (GFR).
Decreased GFR contributes to oliguria and triggers renin/angiotensin release, leading to salt and water retention and edema.

### Renal Cell Carcinoma

Commonly arises in the kidney cortex as a well-circumscribed solid mass, often extending into the renal pelvis and renal vein.
Cut surface often has a variegated golden-yellow appearance due to hemorrhage, necrosis, and cyst formation.
Microscopic picture:
- Clear Cell Type (80%): Large cells with clear cytoplasm arranged in solid masses, cords, or tubules.
- Chromophobe Cell Type (5%): Large cells with granular cytoplasm and distinct cell borders.
- Papillary Renal Cell Carcinoma (10-15%): Cells arranged in cysts with papillary formations.

Clear Cell Renal Cell Carcinoma

Most common variant, accounting for 80% of cases.
Cells contain abundant glycogen and lipids, accounting for the clear cytoplasm.
Can exhibit various growth patterns including papillary, solid, glandular, and trabecular.

Papillary Renal Cell Carcinoma

Makes up 10-15% of renal cell cancers.
Can be sporadic or familial.
Characterized by branching papillae with single layers of large cells with small amounts of cytoplasm and large nuclei.
Often multifocal and bilateral, facilitating early diagnosis.

Chromophobe Renal Cell Carcinoma

Accounts for 5% of renal cell cancers.
Cells originate from cortical collecting ducts.
Characterized by large cells with granular eosinophilic cytoplasm, a perinuclear halo, and prominent cell membranes.
Shows a compact growth pattern and generally has a better prognosis than other variants.

Spread of Renal Cell Carcinoma

Local Spread: Infiltrates the rest of the kidney, early invasion of the renal pelvis, late invasion of the capsule and perirenal fat.
Lymphatic Spread: Primarily to the lumbar lymph nodes.
Blood Spread: Early due to invasion of the renal vein (after renal pelvis invasion). Common metastatic sites include lungs (over 50%), bones (33%), liver, and brain.
Left-sided varicocele can occur with left-sided renal cell carcinoma due to tumor spread.

### Clinical Presentation of Renal Cell Carcinoma

Local spread:
- Painless hematuria
- Loin mass (palpable)
- Costovertebral pain (late symptom after infiltration of the capsule)
Paraneoplastic Syndromes:
- Hypercalcemia, hypertension, polycythemia, Cushing syndrome, and other hormonal issues
Distant metastases:
- Bone fracture, cough, convulsions, left varicocele

### Nephroblastoma (Wilms Tumor)

A malignant embryonal tumor predominantly affecting young children, with the majority of cases occurring before the age of 10.
Originates from nephrogenic blastema - primitive cells that resemble developing kidney tissue.
Rapidly growing and infiltrates the capsule early.
Gross Picture: Markedly enlarged kidney with a huge mass, often irregular and infiltrating the outer surface. Cut section usually appears homogenous, gray, and fleshy.
Microscopic Picture: Comprised of three components:
- Blastema: Primitive cells with scanty cytoplasm.
- Mesenchymal Elements: Fibroblasts, smooth muscle, skeletal muscle, cartilage, or myxomatous tissue.
- Epithelial Component: Malignant epithelial cells forming abortive tubules or glomeruli.

### Spread of Wilms Tumor

Local Spread: Rapidly destroys the remaining kidney tissue, early invasion of the capsule and perirenal fat, late invasion of the pelvis. Direct spread to surrounding intestines and adrenal glands.
Lymphatic Spread: Lumbar lymph nodes (15%).
Blood Spread: Lungs, liver, and brain.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers key concepts related to the anatomy of the kidney, including the nephron's structure and function, as well as common kidney disorders like nephritic syndrome and acute glomerulonephritis. Test your understanding of renal physiology and the implications of kidney diseases.