RENAL DISEASES - The University of the West Indies at Mona
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Transcript RENAL DISEASES - The University of the West Indies at Mona
Renal Diseases
Renal cysts and
Tumors
CYSTIC DISEASES OF
THE KIDNEY
Fluid
filled spaces within the kidney
May involve cortex or medulla or both
May be unilateral or bilateral
May be unilocular or multilocular
May be congenital or acquired
May be sporadic or genetically determined
Clinical significance may be trivial or grave
CLASSIFICATIONS OF RENAL CYSTIC
DISEASES
Polycystic
kidney diseases:
1. Autosomal recessive (ARPKD)
classic infantile polycystic disease
with congenital hepatic fibrosis
2. Autosomal dominant (ADPKD)
Simple renal cysts
Acquired renal cystic disease
Autosomal Recessive Polycystic
Kidney Disease ( ARPKD )
Rare, 1:6-14000 live births
Abnormal gene located on chromosome 6p21
May be still born or neonatal death due to
pulmonary insufficiency
Progressive renal failure
Low specific gravity, mild proteinuria, urine
concentrating defect, anemia, hypertension CCF
Bilaterally symmetrical enlargement of kidneys
Smooth surface with innumerable 1-2 mm cysts
Diffuse fusiform dilatation of the collecting ducts
ARPKD ( Cont. )
Enlarged but normally shaped pelvi-calyceal system
Normal reniform shape complete with fetal lobation
& normal sized (undilated) ureter
Normal glomeruli and tubules
Normal interstitium and no dysplasia
Congenital hepatic fibrosis is almost always present
Normal numbers of nephrons, no interstitial
fibrosis and no dysplasia
Autosomal Dominant Polycystic
Kidney Disease (ADPKD )
World wide, 1:1000 in general population
Accounting for 6% of patients in dialysis and
transplant program
Abnormal gene on short arm of chromosome 16
i.e. 16p13.3(PKD-1). 4q12-22(PKD-2), 3rd locus
found
Present in 3rd-5th decade
Dull loin pain, flank masses. azotemia, positive
family history, hypertension, hematuria, colic etc.
Prograssive renal failure anemia & GFR, Ur
& Cr
ADPKD (CONT.)
Associated
cysts in liver of biliary type, in
pancreas (10%), spleen,thyroid & seminal
vesicle
Vascular anomalies including Berry
aneurysms(33%), aortic aneurysm, aortic root
dilatation and mitral valve prolapse
Diverticular disease of the colon (80%)
ADPKD- Pathological Features
Bilaterally enlarged kidneys (up to 4000 gms)
Diffuse cystic (1-2% cystic nephrons) change with
uninvolved intervening parenchyma
Varying sized, numerous to innumerable generally
spherical unilocular cysts, distributed in cortex and
medulla obscuring normal reniform shape and
corticomedullary junction, containing yellowish to
turbid to brown to black colored fluid
Distorted pelvi-calyceal system
Cysts arising from any part of nephron or collecting
duct
ADPKD- PATHOLOGICAL FEATURES
Cysts
lined by single layer of cuboidal
epithelium
Neoplastic change - uncommon
Simple Renal Cysts
Extremely
common as age advances
Incompletely understood pathogenesis
Commonly associated with scarred kidneys
Asymptomatic with normal renal function
May be solitary/multiple/unilateral/bilateral
Generally unilocular, round to oval of varying
sizes
SIMPLE RENAL CYSTS (Cont.)
Arises
as dilated tubules or collecting ducts
Thin, translucent fibrous wall containing clear
or amber colored serous fluid
ACQUIRED RENAL CYSTIC DISEASE
Secondary
to end-stage renal disease as well
as prolonged dialysis ( 9 months -7 yrs.)
Kidneys are generally small but may be
normal or even enlarged
Common in cortex
Seems to be arising in either proximal or
distal tubules
Neoplastic change are common
RENAL TUMOURS
In
infants and children :
• Nephroblastoma ( Wilms’ tumour )
In adults :
• Renal cell carcinoma
• Renal cell adenoma
• Renal oncocytoma
NEPHROBLASTOMA ( Wilms’ tumour )
Embryonal tumour arising from nephrogenic
blastemal cells
• can differentiate in to several cell lines - blastemal,
epithelial and stromal
• many replicate developing kidneys
Common in young children / uncommon in
neonates and infants
90% in < 6yrs. old ( mean: 3yrs. in boys and 3.5yrs.
in girls )
NEPHROBLASTOMA
Etiology and Pathogenesis
Generally
unknown
World wide i.e. … No environmental factors
Variable incidence in racial groups :
• blacks> whites> Orientals
Familial
tendencies: 1% autosomal dominant
with variable penetrance & expressivity
Genetic predispositions
• WT-1 gene (11p13); WT-2 gene (11p15.5)
NEPHROBLASTOMA
Clinical Features
Most
common genitourinary cancer
Age: 1-3yrs., 98% in <10yrs
Abdominal mass, pain, & hematuria
Usually unicentric, may be multicentric (7%)
or bilateral (5%)
Imaging technique to reveal smaller lesions
No specific tumor markers identified
NEPHROBLASTOMA
Pathologic findings (gross)
Usually
solitary, sharply (well) defined
masses with pseudocapsule
Variable size & weight (60-6350 gms.
with a mean of 550 gms.)
Uniform, pale gray to tan, divided by
prominent fibrous septa in to lobules
May be cystic, hemorrhagic or necrotic
No specific location
NEPHROBLASTOMA
Microscopic findings
Generally
triphasic pattern :
• blastemal, epithelial and stromal cell type
may
contains heterologous elements
“favorable” or “unfavorable” histology
on the bases of nuclear anaplasia i.e. . . .
• marked nuclear enlargement (3x)
• abnormal mitoses i.e. . . . increased DNA
NEPHROBLASTOMA - Spread
Local
Regional
Distant
• lungs
• liver
:
i.e. . . lymphatic
NEPHROBLASTOMA
prognosis and treatment
Depends
upon :
• stage, age and histology
Surgery with chemotherapy for :
• stage I & II with favorable histology
• surgery with chemotherapy and
radiotherapy for higher stages and
unfavorable histology
RENAL CELL CARCINOMA
Hypernephroma
/ Grawitz’s tumour
3% of all adult malignancies
world wide, no racial predispositions
M:F = 1.6:1, 6th decade (mean 55 yrs)
seems to be arising from mature renal
tubules
tobacco - smoked / chewed
RENAL CELL CARCINOMA ( Cont. )
Chromosomal
abnormalities :
• 3p13 - clear or granular cell type
• trisomy 17/ tri-or tetrasomy 7 - papillary
type
Rare familial association
Associated with acquired cysts and / or in
patients on chronic hemodialysis
RENAL CELL CARCINOMA
Clinical Features & Diagnosis
classic
triad :
• hematuria, flank pain and abdominal mass
may be clinically occult, 30% presents with
metastatic lesion
Polycythemia due to erythropoietin
constitutional symptoms
imaging techniques - useful
RENAL CELL CARCINOMA
mode of dissemination
Direct
extension
Vascular
Lymphatic
Lungs, lymph nodes, liver, bone
brain, skin etc.
RENAL CELL CARCINOMA
prognosis
Influenced
by multiple factors :
• tumour size
• infiltrative margins
• histological type
• tumour stage - most important
Can be expressed in terms of histological
types
RENAL CELL ADENOMA
Incidental
findings at autopsy (22%)
Well demarcated, unencapsulated
Pale yellow-gray, discrete cortical mass
Up to 2 cms. in maximum dimension