Tubulointerstitial Disease I Flashcards
What is acute pyelonephritis?
suppurative inflammation of the kidney and the renal pelvis caused by bacterial infection and usually associated with infection of the lower urinary track that has ascended
What is the main cause of acute pyelonephritis?
E. coli (proteus, klebsiella, enterobacter, and pseudomonas also common)
What patient population is prone to UTIs?
women (due to anatomy) and diabetics (due to stasis of urine in the bladder) and older men with BPH or those with uterine prolapse
or vesicoureteral reflex
How else can acute pyelonephritis occur?
Hematogenous spread (common in those with infective endocarditis)
ascending is far more common
What is vesicoureteral reflex?
urethral valves are defective (usually in children) leading to repetitive episodes of acute pyelonephritis (caused by urinary stasis)
can lead to chronic pyelonephritis (pus filled kidneys)
T or F. Liquefactive necrosis is seen in acute pyelonephritis
T. See Yellow raised abscesses on the surface on gross image
abscesses wall off and can be hard to treat with antibiotics
Where does the inflammation in acute PN present first?
in the interstitium and then enters the tubules (generally, glomeruli are usually spared)
in chronic they are affected
How can acute NP obstruct urinary flow?
pus can actually build up and obstruct it and reduce GFR (more in chronic)
What gross endgame does acute PN lead to?
papillary necrosis
What other things can cause papillary necrosis?
Sickle cell
Obstructive pyelonephritis
Diabetes
Analgesics
SODA
In XPN, urine cultures almost always grow what?
P. mirabilis or E. coli.
What is the response to chronic cystitis caused by obstruction?
Hypertrophy with trabeculation of the wall
Or thin and distended bellies from urine retention
Glomeruli have a ____-like appearance in chronic pyelonephritis
thyroid
What are the two forms of chronic pyelonephritis?
Chronic obstructive
- Stones, BPH
- Posterior urethral valves
Chronic reflux
- More common
- Superimposed UTI on congenital reflux and intrarenal reflux
Gross appearance of chronic pyelonephritis?
Dips in gross appearance give a pitting appearance in the cortex due to scarring in the pelvis that almost pulls it downward
blunting and scarring
What are the main causes of acute drug-induced tubulointersittial nephritis (TIN)?
synthetic penicillins (methicillin, ampicillin),
other synthetic antibiotics (rifampin),
diuretics (thiazides),
NSAIDs
numerous other drugs (phenindione, cimetidine)
Describe acute drug-induced tubulointersittial nephritis (TIN)
Thought to be an IgE- and T cell–mediated immune reaction to a drug;
characterized by interstitial inflammation, often with abundant EOSINOPHILS
and edema
What are the main causes of acute tubular injury?
- ischemic
- nephrotoxic (drugs, poison, contrast)
ATI results from ischemic or toxic injury to renal tubules, and is associated with intrarenal vasoconstriction resulting in reduced GFR and diminished delivery of oxygen and nutrients to tubular epithelial cells.
What kinds of casts are seen in acute tubular injury?
granular and tubular as the tubular epithelial cells are sloughed off
What things can cause ischemic acute tubular injury?
- Decreased blood flow
- Mismatched blood transfusions
- Hemolytic crises
Does urine output increase or decrease in ATI?
decrease (sloughed off cells can cause an obstruction)
How can you differentiate between ischemic and nephrotoxic ATI?
Ischemic is more segmental while nephrotoxic damage is more continuous
/diffuse and more prominent in the PT
T or F. In ATI, glomeruli are usually spared
T.
What viral infection is common in renal transplant patients?
BK virus (can shed into urine as decoy cells)
What causes AD PKD?
PKD-1 encoding polycystin-1 and PKD-2 encoding polycystin-2 control epithelial cell development and maturation.
ASD PKD patients also often get what?
often get calcium oxalate crystals
What causes AR PKD?
PKHD1 – most common
Causes abnormal fibrocystin protein – expressed on cilia of renal tubules and bile ducts (so they also have congenital hepatic fibrosis)
Medullary sponge kidney
Congenital, bilateral
Most sporadically
No inheritance pattern
May become symptomatic in young adults
Hematuria and/or urinary tract infection
Calculi in 60%
What causes horseshoe kidney?
trisomy 18 or incidental
