Tubular And Intersitial Diseases Flashcards
__________ is the most common cause of acute renal failure
ATN (acute tubular necrosis)
What are some histological findings in someone with ATN?
- can see tubular epithelial cells that have become detached from BM and then sloughed into the tubular lumen
- some tubules are swollen or vacuolated
- blabbing and loss of brush border of tubules
What happens in the initiation phase of ATN?
36 hrs
- Acute DECREASE in GFR
- rapid ↑ in serum creatinine and BUN
What happens in the maintenance phase of ATN?
- plateau of serum creatinine and BUN
- uremic symptoms, hyperkalemia, metabolic acidosis
Muddy brown granular casts are seen in the urine analysis of what renal pathology?
ATN
List the urinary findings in someone with ATN?
- muddy brown granular casts
- epithelial cell casts
- free epithelial cells
- mild proteinuria
- mild microscopic hematuria
- NO PYURIA
( can also be normal in less severe disease)
What are examples of uremic signs seen in ATN?
- pericardial friction rub and confusion
What are the two main general causes of ATN?
- ischemic insult: hypotension, hemorrhagic/hypvolemic shock
- nephrotoxic insult: endogenous and exogenous
______________ drugs are exogenous nephrotoxic cause of ATN
Aminoglycosides, especially gentamicin
What is the difference in the pattern of necrosis seen in ischemic type ATN vs toxic type ATN
Ischemic: patchy; (PST and ascending limbs of loop of Henle are the most vulnerable)
Toxic: more diffuse and affects the PCT (not affected in ischemic type)
______________ is seen in both types of ATN
Casts in the DCT and CD
What are some features that you would see due to tubular dysfunction in tubulointerstitial nephritis?
- impaired urinary concentration (polyuria which is large volumes of dilute urine and nocturia)
- salt wasting (hyponatremia)
- metabolic acidosis due to inability to excrete acid
ATN has oliguria/polyuria?
Oliguria;
Polyuria is seen in TIN
What is the most common cause for acute TIN?
Drugs: antibiotics, NSAIDs, PPI’s such as omeprazole
Other: infection, idiopathic and sarcoidosis (sarcoidosis will have granuloma TIN)
What kind of TIN would be caused by pyelonephritis?
chronic TIN
Drug induced interstitial nephritis will have prominent ___________ and mononuclear cell infiltrate. This is type ____ TIN
Eosinophils; type 1
What drugs most commonly cause TIN?
- NSAIDs
- omeprazole (PPI)
- antibiotics
What is a typical presentation of someone who most likely has TIN?
- patient can take a drug (NSAIDs, antibiotics, PPI) and then 2 weeks later (1st exposure) or 3-5 days later (2nd exposure) will have: fever, rash, and/or eosinophilia
Treatment for AIN:
- stop taking the drug
- oral steroids
_________ and _________ infections could be a source for bloodstream causes for acute pyelonephritis
Bacteria endocarditis; septicemia
What kind of people are at more risk for ascending infection causes for acute pyelonephritis
- women
- males with BPH or vesicourethral reflux
The predominant cell in acute pyelonephritis is ________ inside the tubules a
Neutrophils/ neutrophilic casts (WBC cast)
What are some complications of acute pyelonephritis?
- papillary necrosis
- pyonephrosis (pus collecting in the renal pelvis)
- perinephric abscess
Blunting of the calyces and depressed areas on gross specimen of the kidney is seen in what renal disease?
Chronic pyelonephritis
Thyroidization of the tubules is a form of tubular atrophy and is seen in ________
Chronic pyelonephritis
What are the two forms of chronic pyelonephritis
- chronic obstructive pyelonephritis: incompetent posterior urethral valves or kidney stones
- reflux nephropathy (vesicourethral reflux)
Preferentially scarring and calyceal dilation at the poles is seen in _______________
VUR form of chronic pyelonephritis
What are some gross features of a kidney that has undergone the obstructive form of chronic pyelonephritis?
- diffuse dilation of calyces and scarring
What are some common causes of obstructive uropahty (obstruction at any level in the urinary tract from urethra to renal pelvis)
- BPH
- bladder cancer
- kidney stone
- retroperitoneal adenopathy
- papillary necrosis due to sloughed papillae obstructing the tract
What is the most common type of renal stones?
Calcium containing: calcium oxalate and calcium phosphate
____________ renal stones are typically secondary to infection
Struvite (Mg/ammonium phosphate);
These stones are also very large and to take the shape of the renal pelvis when they get lodged there
With _________ stones in the kidney, you can see granulomatous inflammation
Uric acid
Abrupt onset of flank pain radiation to groin (intermittent) is indicative of _______
Renal stone that is lodged in the ureter (pain is described as renal colic)
What are 3 ways to prevent renal stones?
- ↑ fluid intake
- ↓ sodium diet (calcium and sodium get absorbed together in the PCT so by ↓ sodium will lead to ↓ urinary calcium excretion)
- alkalinization of urine to ↑ solubility of uric acid
____________ urine has ↑ solubility for uric acid
Alkaline
