Page 501 - Concise Pathology for Exam Preparation ( PDFDrive )

486 SECTION II Diseases of Organ Systems

Q. Differentiate between RCC and Wilms tumour.

Ans. Differences between RCC and Wilms tumour are listed in Table 16.13.

TABLE 16.13. Differences between RCC and Wilms tumour

Features RCC Wilms tumour
Age Adults Children
Associated genes VHL, MET WT-1 and -2
Gross • Polar distribution • Large, rapidly growing mass, which
overwhelms the kidney and can
replace it entirely
• Variegated appearance • Homogeneous appearance
• Bright yellow to grey-white with • Tan to grey
prominent cystic change and • Haemorrhage and cystic change
haemorrhage occasionally seen
Microscopy Solid to tubular growth pattern, Classic triphasic combination of
round cells with clear or granular blastemal (sheets of small blue cells),
cytoplasm (glycogen and lipid); epithelial cells (arranged as abortive
may show papillae (papillary vari- tubules or glomeruli) and stromal cells
ant), nuclear atypia and giant cells (fibrocystic or myxoid in nature)
Paraneoplastic syndromes Very common Usually not seen
Tendency to invade renal vein Common Usually not seen
Prognosis Comparatively poor Better

Q. Enumerate the causes of a small contracted kidney.

Ans. Causes of a small contracted kidney:
1. Nephrosclerosis: Symmetrically atrophic kidneys with fine, pale, granularity (resembles
grain leather)
2. CGN: Symmetrically contracted kidneys with red brown, diffusely granular surface,
corticomedullary junction (CMJ) not well made out
3. CPN: One or both kidneys may be involved (asymmetric, diffuse or patchy involve-
ment), coarse scars, poorly defined CMJ, thickening of pelvic mucosa with yellow tinge
and pelvocalyceal deformities
4. Late stages of diabetic nephropathy
5. Late stages of amyloidosis
6. Multiple myeloma
7. Gout
8. Senile nephritic syndrome
A contracted kidney with large scars is most commonly the result of:
1. Old infarcts
2. Polyarteritis nodosa

Q. Enumerate the causes of a large white kidney.
Ans. Causes of a large white kidney (pale, soft and grey kidney which weighs more than
250 g) are:
• Acute diffuse GN and RPGN
• Lipoid nephrosis
• Early DM and amyloidosis
• SLE
• Toxaemia
• Leukaemia
• Malaria
• Irradiation nephritis/chemotherapy

mebooksfree.com