Renal 3 Flashcards
is a hereditary disorder characterized by multiple expanding cysts of both kidneys that ultimately destroy the renal parenchyma and cause renal failure.
AUTOSOMAL DOMINANT (ADULT) POLYCYSTIC KIDNEY DISEASE
Inheritance pattern ADKPD
autosomal dominant
with high penetrance
ADKPD bilateral or unilateral?
Bilateral
PKD1 gene is located on
chromosome 16p13.3
Encodes an integral membrane protein named
polycystin-1.
PKD1 gene
Polycystin-1 is expressed in tubular epithelial cells,
particularly those of the
distal nephron
Located on chromosome 4q21.
PKD2 gene
PKD2 gene Encodes an integral membrane protein named _______
polycystin-2.
polycystic disease pathogenesis
ciliacentrosome complex
Act as mechanosensor to monitor changes
in fluid flow and shear stress.
single non-motile primary cilium.
Regulate ion flux and cellular behavior,
including cell polarity and proliferation
single non-motile primary cilium.
Gross polycystic kidney disease
● Kidneys are bilaterally and large
- External: mass of cysts with no intervening parenchyma
Microscopic polycystic disease
- The cysts may be filled with a clear, serous fluid or
with turbid, red to brown, sometimes hemorrhagic fluid.
-The cysts arise from the tubules throughout the
nephron and therefore have variable lining
epithelia
clinical features polycystic disease
- asymptomatic (many patients)
- renal colic
- dragging sensation
- insidious onset of hematuria
- proteinuria, polyuria, hypertension
- PKD2: older age, later devt of renal failure
- tend to have extrarenal congenital anomalies.
- azotemia- no symp
- Uremia- w/ symp
most common ARPKD
Perinatal, neonatal
ARPKD is mostly caused by mutations in the
PKHD1 Gene
PKHDA1 gene is located at
chromosome region 6p21-p23
PKHDA1 encodes for
fibrocystin
Gross ARPKD
- kidneys are enlarged and have a smooth external appearance
- sponge-like appearance
microscopic ARPKD
-Cylindrical or less commonly saccular dilation of all
collecting tubules
-The cysts have a uniform lining of cuboidal
cells, reflecting their origin from the collecting ducts.
-In almost all cases, the liver has cysts associated
with portal fibrosis and proliferation of portal bile
ducts.
CLINICAL FEATURES ARPKD
-peculiar hepatic injury characterized by bland periportal fibrosis and
proliferation of well-differentiated biliary ductules, now termed congenital hepatic fibrosis
-older children: portal hypertension with splenomegaly
T or F
Congenital hepatic fibrosis sometimes occurs in the
absence of polycystic kidneys or has been reported
in the presence of adult polycystic kidney disease.
T
2 categories of CYSTIC DISEASES OF RENAL MEDULLA
- Medullary Sponge Kidney
2. Nephronophthisis
medullary sponge kidney is restricted to multiple cystic dilatations of the
collecting ducts in the medulla