Nephritic syndrome & UTI & nephrolithiasis Flashcards
glomerular disorders characterized by glomerular inflammation and bleeding
nephritic syndrome
- limited proteinuria (<3.5 g/day)
- oliguriza & azotemia
- salt retention with periorbital edema & HTN
- RBC casts and dysmorphic RBCs in urine
nephritic syndrome
immune-complex deposition activates complement; C5 attracts neutrophils –> hypercellualr, inflamed glomeruli on biopsy
nephritic syndrome
Nephritic syndrome that arises after group A beta-hemolytic streptococcal infection of the skin (impetigo) or pharynx; may occur after infxn w/ nonstreptococcal organisms, too!
PSGN
Kid presents 2-3 weeks after infection w/ hematuria, oliguria, HTN, periorbital edema
PSGN
hypercellular, inflamed glomeruli on H&E; mediated by immune complex deposition (granular IF); subepithelial humps on EM
PSGN
PSGN treatment
supportive
PSGN complications
kids rarely progress to renal failure; some adults develop RPGN
nephritic syndrome that progresses to renal failure in weeks to months
RPGN
crescents (fibrin + macrophages) in Bowman space of glomeruli
RPGN
IgA immune complex deposition in mesangium of glomeruli
IgA nephropathy (Berger disease)
kid w/ episodic gross or microscopic hematuria w. RBC casts, usually following mucosal infections (e.g. gastroenteritis); may slowly progress to renal failure
IgA nephropathy (Berger disease)
Inherited defect in type IV collage (usu X-linked) –> thinning and splitting of glomerular basement membrane
Alport syndrome
Isolated hematuria + sensory hearing loss + ocular disturbances
Alport syndrome
linear IF pattern (anti-basement membrane antibody) in RPGN
goodpasture syndrome
antibasement membrane antibody
goodpasture syndrome
granular IF (immune complex deposition) in RPGN
PSGN (most common) or diffuse proliferative glomerulonephritis
what defines a nephrogenic strain?
carry M protein virulence factor
6 etiologies of RPGN
Goodpasture syndrome PSGN diffuse proliferative glomerulonephritis Wegener gramulomatosis microscopic polyangitis Churg-Strauss syndrome
Negative IF (pauci-immune) in RPGN
Wegener’s
microscopic polyangitis
Churg-Strauss
c-ANCA
Wegener
p-ANCA
microscopic polyangiitis or Churg Strauss
p-ANCA plus granulomatous inflammation, eosinophilia, and asthma
Churg-Strauss
infection of urethra, bladder, or kidney; most commonly arises due to ascending infxn (F»M)
UTI
Risk factors for UTI
sex, urinary stasis, catheters
infection of the bladder
cystitis
dysuria, urinary frequency + urgency, suprapubic pain without systemic signs (fever)
cystitis
urianalysis findings of cystitis
cloudy urine with > 10 WBCs/hpf
Positive leukocyte esterase (due to pyuria) and nitrites (bacteria convert nitrates to nitrites)
dipstick findings of cystitis
culture findings of cystitis
> 100,000 colony forming units (gold standard)
causal agents of UTI
e coli (80%0 staph saprophyticus klepsiella pneumonia proteus mirabilis enterococcus faecalis
pyuria
pus in the urine
distinguishing feature of proteus mirabilis cystitis
alkaline urine w/ ammonia scent
sterile pyuria (pyruria w/ negative urine culture)
urethritis due to chlamydia or N gonorrhoeae
dominant presenting sign of urethritis
dysuria
pyelonephritis
infection of the kidney
vesicoureteral reflux
reflux from bladder up to ureter
fever, flank pain, WBC casts and leukocytosis
pyelonephritis
most common pathogens causing pyelonephritis
E coli (90%)
Enterococcus faecalis
Klebsiella species
scarring at upper and lower poles of kidney
characteristic of vesicoureteral reflux
leads to renal cortical scarring with blunted calyces
chronic pyelonephritis
“thyroidization” of the kidney (atrophic tubules containing eosinophilic proteinaceous material resemble thyroid follicles)
chronic pyelonephritis
interstitial fibrosis and atrophy of tubules due to multiple bouts of acute pyelonephritis
chronic pyelonephritis
causes of chronic pyelonephritis
vesicoureteral reflux in kids or obstruction (BPH or cervical carcinoma)
precipitation of a urinary solute as a stone
nepholithiasis
risk factors for nephrolithiasis
high concentration of solute in the urinary filtrate and low urine volume
nephrolithiasis presentation
colicky pain with hematuria and unilateral flank tenderness
what happens if someone does not pass a kidney stone within hours?
may require surgical intervention
most common type of kidney stone
calcium oxalate and/or calcium phosphate
cause of calcium oxalate and/or calcium phosphate stone
idiopathic hypercalcemia + Crohn
Treatment of calcium oxalate and/or calcium phosphate stones
Hydrochlorothiazide (calcium sparing diuretic)
Most common cause is infection with urease positive organisms (Proteus vulgarism or Klebsiella); alkaline urine leads to formation of stone
ammonium magnesium phosphate stone
staghorn calculi in renal calyces, wh/ act as nidus for urinary tract infections
ammonium magnesium phosphate
treatment of ammonium, magnesium, phosphate stones
surgery to remove stone (due to size) and eradication of pathogen (to prevent recurrence)
Radiolucent kidney stone
uric acid kidney stone
risk factors for uric acid stone
hot, arid climates, low urine volume, acidic pH
most common stone seen in patients with gout; hyperuricemia (in leukemia or MPD) increases risk
uric acid stone
treatment of uric acid stone
hydration and alkalization of urine (potassium bicarbonate); allopurinol is also administered in patients with gout
associated with cystinuria (a genetic defect of tubules that results in decreased reabsorption of cysteine)
cysteine kidney stones
treatment of cysteine kidney stone
hydration and alkalinization of urine; note cysteine may also form staghorn caliculi
staghorn caliculi in adult
ammonium magnesium phosphate stone
staghorn caliculi in kid
cysteine kidney stone
