The Kidney Flashcards
Amount of blood converted by kidneys per day
1700 L of blood per day into about 1 L of urine
4 basic morphologic components of kidney diseases
Glomeruli, tubules, interstitium, blood vessels
All four components of the kidney are ultimately damaged
End-stage kidneys
A biochemical abnormality that refers to an elevation of BUN and creatinine levels, and is related largely to a decreased glomerular filtration rate (GFR)
Azotemia
Encountered when there is hypoperfusion of kidneys that impairs renal function in the absence of parenchymal damage
Prerenal azotemia
Seen whenever urine flow is obstructed distal to the kidney
Postrenal azotemia
Term when azotemia becomes associated with a constellation of clinical signs and symptoms and biochemical abnormalities
Uremia
Organs secondarily involved among uremic patients
Uremic gastroenteritis
Peripheral neuropathy
Uremic fibrinous pericarditis
Clinical entity caused by glomerular disease and is dominated by the acute onset of either grossly visible hematuria or microscopic hematuria with dysmorphic red cells and red cell casts on urinalysis, diminished GFR, mild to moderate proteinuria, and hypertension
Nephritic syndrome
Risk for development of renal cell carcinoma
Dialysis-induced cystic disease
Infectious agents responsible for post-infectious GN
Streptococcal pharyngitis or impetigo (GABHS) Staphylococcal endocarditis Pneumococcal pneumonia Hepatitis B or C HIV Malaria
Glomerular disease with increased numbers of epithelial, endothelial and mesangial cells and neutrophils infiltrating in and around the capillary loops, making it poorly defined.
Postinfectious GN
Immune deposits appear in a bumpy granular pattern consisting mainly of IgG, IgM, and C3 in immunofluorescence
Post-infectious GN
On e-microscopy, immune deposits are predominantly subepithelial, producing subepithelial humps above the basement membrane and below the podocyte
Post-infectious GN
Serology of post-strep GN
Elevated ASO
Anti DNase B
Antihyaluronidase titers
Aka crescentic GN
RPGN
Formed by proliferating parietal epithelial cells
Crescent formation
Types of RPGN
Type 1: anti-GBM antibody disease such as goodpasture syndrome
Type 2: immune complex deposition such as SLE or post-infectious GN
Type 3: Vasculitis often pauci-immune forms
Markedly thickened capillary loops in SLE
Wire-loop lesion
Patient presents with hematuria, moderate to severe proteinuria with edema, hypertension, and hemoptysis. There is detectable circulating anti-GBM antibody.
Goodpasture syndrome
Patient presents with hematuria, moderate to severe proteinuria with edema, and hypertension. There is detectable antineutrophilic cytoplasmic antibody (ANCA).
Microscopic polyangiitis
In immunofluorescence, there is bright green positivity with antibody to IgG with a smooth, diffuse, linear pattern.
RPGN
Anti-GBM antibody is directed at which domain of the collagen.
Noncollagenous domain of the alpha-3 chain of type IV collagen
Patient presents with increasing serum BUN and creatinine, decreasing UO, and urinary sediment containing RBC and RBC casts
RPGN
Presence of urinary dysmoprhic RBCs and RBC casts along with oliguria and hypertension
Nephritic syndrome
There is focal segmental necrotizing GN and glomerular crescent with tubular atrophy noted. Patient has increased ANCA. Immunofluorescence shows minimal deposition of IGs or complement in the glomeruli and renal vessels.
Microscopic polyangiitis
Normal size and weight of an adult kidney
11 to 15cm in length, weighing 125 to 200 grams
Why is there easy focal infarction in an occluded branch of renal artery?
Branches of renal artery within each kidney have no anastomoses.
Functions of the kidney (4)
Excretion of waste products
Acid-base balance
Salt and water volume with regulation of blood pressure
Maintenance of rbc mass through elaboration of EPO
Main composition of the glomerular basement membrane
Type IV collagen
Found beneath the capsule of the developing fetal kidney and is composed of primitive dark blue cells in which development of glomeruli and tubules is taking place and from which the new cortex forms
Nephrogenic zone
The absence of formation of a body part during embryogenesis
Agenesis
Direct result of renal agenesis to pregnancy
Oligohydramnios leading to pulmonary hypoplasia.
Renal hypoplasia with a granular surface and a few scattered, shallow cortical scars
Renal acquired hypoplasia
Renal hypoplasia that has no cortical scars with reduction in number and size of renal lobes and pyramids.
True congenital hypoplasia
Frequent fusion site of horseshoe kidney
Lower renal poles
A bilateral process with mutations in the PKD1 gene encoding polycystin-1 and PKD2 gene encoding polycystin-2.
Autosomal dominant polycystic kidney disease
Proteins that are part if ciliated tubular epithelium regulating intracellular calcium
Polycystin
Other locations of cysts in a patient with ADPKD
Liver, pancreas, spleen, intracranial berry aneurysm
Middle aged patient who, for the first time, presented with hematuria, proteinuria (>=< 2g/day), polyuria and hypertension
ADPKD
Bilaterally massively enlarged kidneys in a term neonate
Autosomal recessive polycystic kidney disease
Subcategories of ARPKD
Perinatal, neonatal, infantile, juvenile
Characterized by PKHD1 gene mutation with presence of associated hepatic lesions ie congenital hepatic fibrosis leading to complications from portal hypertension
ARPKD
Bilaterally and symmetrically enlarged kidney. On cut sections show numerous glistening cysts are small, about 1 to 2mm in diameter, but uniformly distributed throughout the parenchyma to produce a spongy appearance and there is no distinguishable cortex or medulla.
ARPKD
Microscopic appearance is characterized by many cysts involving the collecting ducts, often elongated and radially arranged or saccular. The cysts have a uniform lining of cuboidal cells.
ARPKD
Seen as expanded portal regions with collagenous fibrosis and a surrounding proliferation of radially arranged portal bile ducts
Congenital hepatic fibrosis
Asymmetrical kidneys with irregularly sized cysts separated by dense stroma. It may be a part of Meckel-Gruber syndrome
Multicystic renal dysplasia
Microscopically disordered organ development composed of irregular vascular channels, islands of cartilage, undifferentiated mesenchyme, and scattered immature collecting ductules in a fibrous stroma with cysts.
Multicystic renal dysplasia
Bladder dilation and hypertrophy, bilateral hydroureter and numerous small cysts in the renal cortices due to either urethral atresia or posterior urethral valves
Congenital urinary obstruction with cystic change
Pulmonary hypoplasia
Congenital renal diseases or urinary tract outflow anomalies
Potter facies with flattened nose and prominent infraorbital creases
Talipes equinovarus
Joint contractures
Oligohydramnios sequence
1- to 7-mm cysts involving the medulla of the kidney resulting from nonprogressive dilation of the distal portion of the collecting ducts and tubules in the renal papillae. Some cases appear in conjunction with marfan syndrome, ehlers-danlos syndrome, and caroli disease
Medullary sponge kidney
Medullary cysts up to 2cm concentrated at the corticomedullary junctions. There is ongoing tubulointerstitial injury from tubular basement membrane disruption. Glomeruli are usually spared. Patients have polyuria, sodium wasting, and tubular acidosis.
Nephronophthisis
Patients with chronic renal failure who undergo dialysiss for many years, developing multiple cortical cysts
Dialysis-induced cystic disease
Due to obstruction with progressive interstitial fibrosis and/or oxalate crystal deposition in ESRD. When such cysts develop, they are more numerous than the common simple renal cysts, but usually less numerous than the cysts with ADPKD.
Acquired renal cystic disease
Diffusely thickened and prominent capillary loops, but overall glomerular cellularity us not increased.
Membranous nephropathy
Defined as more than 3.5g of urine protein (mainly albumin) per day per 1.62 meter squared body surface area
Nephrotic syndrome
Presence of autoantibodies to M-type phospholipase A2 receptor
Membranous nephropathy
Jones silver stain. Highlights the proteinaceous basement membranes of capillary loops in black. There are characteristic “spikes” involving the capillary loops.
Membranous nephropathy
Immunofluorescence pattern has a bumpy or granular staining pattern as a result of irregular deposition of immune complexes within the basement membranes of the glomerular capillary loops.
Membranous nephropathy
E-microscopy shows darker electron dense immune deposits scattered within the thickened capillary basement membrane. The “spikes” seen with silver stain are lighter areas representing the intervening increased matrix of basement membrane between the darker immune deposits.
Membranous nephropathy
Normal glomerulus on light microscopy. Electron micrograph shows normal fenestrated endothelium, normal thickness basement membrane and effacement of podocytes.
Minimal change disease
An area of collagenous deposition at the vascular pole of the glomerulus involving some glomeruli and part of the glomerulus. Either nephritic or nephrotic syndrome.
Focal segmental glomerulonephritis
Components of the slit diaphragm between podocyte foot processes. Involved in FSGS.
Nephrin and podocin
On light microscopy there is mesangial proliferation, increased mesangial matrix, mesangial immune complex deposition, accentuation of the lobular architecture, and increased leukocytes. On e-microscopy, there is splitting and reduplication of basement membrane.
Membranoproliferative GN type 1
Both nephrotic and nephritic features
Membranoproliferative GN
Changes that occur when the mesangial cells, which has a macrophage-like function) tries to phagocytose subendothelial immune deposits, but makes a mess of the GBM in the process.
Splitting and reduplication of basement membrane
The dense deposits within the basement membrane often coalesce to form a ribbon-like mass of deposits. This results fron activation of the alternative complement pathway.
Membranoproliferative GN type 2
Glomerular disease with an X-linked dominant inheritance pattern resulting fro mutations in the alpha-5 chain of type IV collagen (COL4A5)
Alport syndrome
Hematuria with slowly progressive proteinuria accompanied by nerve deafness, lens dislocation, cataracts, and corneal dystrophy. Renal tubular cells appear foamy because of the accumulation of neutral fats and mucopolysaccharides. There is thickening and thinning with splitting of basement membrane.
Alport syndrome
Microscopic appearance shows fibrotic cortex, sclerotic glomeruli from hyaline obliteration, scattered interstitial chronic inflammatory cell infiltrates, and thickened arteries. Tubules are often dilated and filled with pink casts and give an appearance of “thyroidization.”
End-stage renal disease
Component of glomerulus with macrophage-like function
Mesangial cells
The most common form of GN.
IgA nephropathy
Antiglycan antibodies form against abnormally glycosylated IgA1 and deposited within the mesangium of the glomeruli. There is mesangial hypercellularity, segmental glomerulosclerosis or adhesion, tubular atrophy and interstitial fibrosis.
IgA nephropathy
Analgesic nephropathy may develop into what cancer
Urothelial carcinoma of the renal pelvis
Chromophobe renal cell CA originated from
Collecting ducts
Papillary renal call CA originated from
Distal convoluted tubule
Clear cell renal cell CA originated from
Proximal convoluted tubule
