Tubulointersitial Nephritis Flashcards
what is the most common cause of kidney disease?
UTI’s (asymptomatic bacteruria; lower UTI’s= urethritis, cystitis; pyelonephritis)
urethritis
infection of urinary bladder
These infections can be quite common esp in women
pyelonephritis
infection spreads to the kidney (Infxn kind of moves upstream)
what is the most common bacteria found in UTI’s?
85% gram (-) bacilli
E.col, Proteus, Klebsiella, Enterobacter
(can also be caused by fungi and viruses)
how do most infections reach the kidney?
Most of the infections are ASCENDING infxns
Colonization of lower portion of urinary tract → enters bladder → eventually reaches the kidney
lower urinary tract infections
usually don’t have to worry about it affecting the kidneys
Most common= infxns of the ureter
what other ways can the kidney develop an infection other than a ureter infection?
Small portion of pts have UTI that bact enter the kidney through the circulation= sepsis and endocarditis
endocarditis= bact colonize valves in the heart → can travel and enter the kidney
calculi
stones
causes obstruction of outflow of urine and increased residual vol
vesicoureteral reflux
• Reflux= backflow of urine
• Vesicoureteral valve= Prevents flow of urine from urinary bladder to ureter
○ When the valve doesn’t work, urine can flow back up and bring bact with it
• can be caused by congenital absence or shortening of the intravesical portion of the ureter, bladder infection, or spinal injury
intrarenal reflux
urine flowing from the pelvis back
pyelonephritis definintion
renal lesion assoc with the UTI
what is pyelonephritis most commonly caused by?
bact infection
types of pyelonephritis
○ Acute= 1-3 weeks; may go away on its own
§ Can develop w/o any special circumstances= everyone can experience it
○ Chronic= progressive; may lead to more serious complications
§ Usually with an underlying condition
why can pregnancy increase risk of infection?
b/c you may have compression of urethra and urinary bladder
risk factors for acute pyelonephritis
obstruction, catheter, vesicoureteral reflux, PREGNANCY, older men, preexisting renal lesions, DM, immunosuppression
histology of acute pyelonephritis
multi-lobulated nuclei
complications of acute peylonephritis
- papillary necrosis
- pyonephrosis= sac of connective tissue filled with pus
- perinephric abscess
papillary necrosis most commonly occurs when you have ___
DM or UTI
clinical picture of acute pyelonephritis
sudden onset, pain at costovertebral angle, fever, dysuria, pyuria (presence of pus in the urine), pus casts (formations which are formed in the tubules)
polyomavirus nephropathy
can occur in kidney transplant pts
viral infection
chronic pyelonephritis and reflux nephropathy is assoc with ___
pathologic involvement of the calyces and pelvis
** Inflammation → tissue is destroyed → healing phase → scarring → scars cause significant destruction of kidney architecture
Leads to end stage renal disease
forms of chronic pyelonephritis
- ) reflux nephropathy= occurs early in childhood
2. ) chronic obstructive pyelonephritis= recurrent infections lead to recurrent bouts of renal inflammation and scarring
morphology of chronic pyelonephritis
• Do not have normal structures
○ No tubules, no glomeruli, nephrons are gone
diagnosis of chronic pyelonephritis
Reflux nephropathy is often discovered when HTN in children is investigated
Loss of tubular function= gives rise to polyuria and nocturia
x-ray= asymmetrically contracted kidneys with course scars and blunting of calyceal syst
