Tubulointerstitial & Vascular Kidney Flashcards
What is the definition fo acute tubular injury?
Causes?
Pathogenesis?
- Definition
- injury to tubular epithelial cells & acute decline in renal function
- Causes
- ischemic (hypoxia, hypotension, embolus, etc)
- toxic (myoglobinuria, hemoglobinuria, - damage to skeletal muscle/hemolysis- immune, toxin, or mechanically mediated)
- combination
- Pathogenesis
- tubule cell injury (epithelial cells)
- very metabolically active cells, so v. sensitive to ischemia & toxic injury
- when injured, cell will start swelling b/c taking on water & may have vacoulization of epithelial cels & they can die & slough off into tubular lumen
- decrease GFR & urine output
- disturbance of blood flowinjured tubular cells will have backflow of ultrafiltrate, which leads to interstitial edema
- tubule cell injury (epithelial cells)
Where do we see patterns of acute tubular injury for both ischemic type & toxic type?
Distal collecting tubules & collecting ducts (& contain casts)
In the proximal tubules- toxic is more diffuse whereas ischemic is more patchy
What pathology is shown in the provided image?
Acute Tubular Injury
* = injured - swollen up
will sometimes be vacoulated
may see some apical blebbing (membrane bulging outward during cell death)
Arrows = sloughed epithelial cells in the lumens
What pathology is shown in the provided image?
Acute tubular injury
granular cast in someone who had rhabdomyolysis (myoglobin casts) - both myoglobin & iron are toxic to epithelial cells
casts can obstruct the lumen & urine flow
What pathology is shown in the provided image?
Acute Tubular Injury from Ethylene Glycol (antifreeze)
- Left
- Notice the large number of vacoules in the cytoplasm- cells are swollen
- notice the crystals (calcium oxalate)
- Right
- with polarized light microscopy, the crystals show up white (calcium oxalate)
What is tubulointerstitial nephritis?
Causes?
Clinical Presentation?
- Inflammation and injury of tubules & interstitium
- Causes
- glomerulonephritis
- infections
- toxins (& medications)
- metabolic diseases
- neoplasms
- obstruction
- immune reactions
- vascular diseases
- Clinical presentation
-
NO nephritic or nephrotic syndrome
- will not have cola colored urine or huge amounts of protien in urine
- defects in tubular function are present
- inability to concentrate urine
- salt wasting
- metabolic acidosis
- isolated defects in tubular reorption or secretion
-
NO nephritic or nephrotic syndrome
What histological features are present in acute tubulointerstitial nephritis compared to chronic?
- Acute
- Interstitial edema
- WBC (neutrophils and eosinophils) infiltrate in tubules adn interstitium
- tubular njury
- NO fibrosis or tubular atrophy
- Chronic
- WBC (lymphocytes & monocytes) infiltrate in tubules and interestitium
- prominent interstitial fibrosis
- __going to see a lot of collagen
- widespread tubular atrophy
- shrunken cells
- NO edema, neutrophils or eosinophils
What is the name for renal infection?
Describe the pathways through which this occurs.
pyelonephritis
- Ascending infection - results from combination of urinaty bladder infection, vesicoureteral reflux, & intrarenal reflux
- Etiologic agents
- E. coli
- Proteus
- Enterobacter
- particularly seen in patients with vesicoureteral reflux or intrarenal reflux
- Etiologic agents
- Hematogenous infection (top) results from bacteremic seedng of the kidneys
- Etiologic Agents
- Staph & E.coli
- Etiologic Agents
What pathology is depicted through the procedure shown in the provided image?
Vesicoureteral Reflux - Voiding Cystogram
Dye injected into the bladder refluxes intot both dilated ureters, filling the pelvis & calyces
What pathology is shown in the provided image?
Acute Pyelonophritis
- the cortical surface (beneath the peeled capsule) showsn multiple small abscesses (white open arrow) of hematogenous pylonephritis
What pathology is shown in the provided image?
Acute Pyelonephritis
- Autopsied kidney with acute phyelonephritis & cortical ascess (white curved arrows)
- Pale area of abscess with neutrophils (left) is surrounded by increased vascularity and chronic inflammation
- will typically see some granulation tissue surrounding abscesses & inflammation on residual kidney
What pathology is shown in the provided image?
Acute pyelonephritis
Acute neutrophilic (notice the nuclei have multiple lobes & get “nuclear dust”) exudate with tubules (Center) adn interstitial inflammation
What pathology is shown in the provided image?
Acute Pyelonephritis
Periodic acid-Schiff shows neutrophil casts (black open arrow) within the cortical tubules
What pathology is shown in the provided image?
It is a complication of what condition?
Papillary Necrosis
Complication of pyelonephritis
The necrotic papilla is sharply demarcated by a hemorrhagic zone (black curved arrow)
What pathology is shown in the provided image?
Papillary Necrosis
severe acute pyelnephritis an papillary necrosis
surrounding the necrotic papilla is a wll-defined hemorrhagic zone (black curved arrow, mid-right)
The necrotic area at bottom – ( black solid arrow lower left) shows no resideual viable cells
What pathology is shown in the provided image?
Polyomavirus nephropathy
polyomavirus typically acquired in childhood & it lies dormant - can be reactivated in patients on immunosuppressants (especially renal transplant patients)
Infection of renal tubular epithelial cells (notice the vacoules/inclusion w/in the thin rim of nuclear material)
inflammation is mostly chronic inflammation (lymphocytes- dar & squigly looking)
How does chronic pyelonephritis develop & it is most common in what demographic?
Due to repeated episodes of acute pyelonephritis
most common in people who have vesicoureteral reflux / some other obstructive problem
Typically have course scars that are polar & associated with underlying blunted calyces
What pathology is shown in the provided image?
Chronic Pyelonephritis Gross Appearance
(left) is irregularly scarred
The cut section (right) reveals blunting and loss of several papillae
v. indistinct between the renal calyces & papilla (absent/flatened)
What pathology is depcted by the provided images?
- Left image
- right aspect is an uninvoled part of the kidney
- left aspect is subject to chronic inflammation (little blue cells)
- interstitial fibrosis
- scarring (not easily seen but present)
- tubules less numerous
- typically involving tubles, not the glomeruli
- Right image
- tubular atrophy & may get a lot of hyaline casts - proteins from tubules that form matrixes that other casts form as well
What pathology is shown in the provided image?
Drug-Induced Interstitial Nephritis
chronic inflammatory infiltrate, with many eosinophis (red) and many mononuclear leukocytes (lymphocytes and monocytes)
What pathology is shown in the provided image?
Urate Nephropathy
Granulomatous inflammation and fibrosis outline the slender uric acid crystals in the renal medulla (arrow)
What pathology is shown in the provided image?
Nephrocalcinosis
calcium phosphate deposited in the kidney (anything that causes hypercalcemia) - typically stain a dark purple color
What pathology is shown in the provided image?
Light Chain Nephropathy (Myeloma Kidney)
Angulaed and tubular casts (circled) surrounded by macrophages, some of which are multinucleated (arrow)- formed from combo of IgA light chain deposits combined with tam horsfall protein- an obstruct the kidney
People who have plasma cell neoplasms - particularly multiple myeloma
What pathology is shown in the provied image?
Hyaline arteriosclerosis
(cyan solid arrow)
commonly found in hypertension, diabetes, and other disorders
Smudgy, eosinophilic & narrow lumen (compromises blood flow)
