Renal-Pathology Flashcards
What does the presence of casts in urine indicate? What causes RBC casts? WBC casts? Fatty casts? Granular casts? Waxy? Hyaline?
Hematuria/pyuria originates in the glomerulus or renal tubules
RBC=glomerulnephritis, malignant hypertension WBC=tubulointerstitial inflammation, acute pyelonephritis, transplant rejection Fatty casts (Oval fat bodies)=nephrotic Granular (muddy brown) = acute tubular necrosis Waxy= ESRD/CRF Hyaline=Non specific, maybe normal, concentrated urine
Concerning glomerular disorders, what does the term focal mean? Diffuse? Proliferative? Membranous? Primary? Secondary?
focal? 50% Proliferative? hypercellular glomeruli Membranous? Thickening of GBM Primary? primarily of kidney Secondary? systemic disease impacting glomerulus
What is the overall cause of nephritic syndrome? Lab findings? Specific causes?
GBM disruption
Hypertensin Incr. BUN and creatinine oliguria hematuria RBC casts in urine Proteinuria in subnephrotic range (<3.5 g/day)
Acute PSGN Rapidly progressive glomerulonephritis IgA nephropathy (Berger disease) Alport syndrome Membranoproliferative GN
What is the overall cause of nephrotic syndrome? Lab findings? Specific causes? Are the causes primary or secondary? How can it lead to a hypercoag state? How can it lead to infection?
Podocyte disruption–>charge barrier impaired
Proteinuria (>3.5 g/day) Hypoalbuminemia Hyperlipidemia Edema Frothy urine Fatty casts
Focal Segmental Glomerulosclerosis (prim. or sec.) Minimal change disease (prim or sec) Membranous nephropathy (1 or 2) Amyloidosis (2) Diabetic glomerulonephropathy (2)
Loss of ATIII in urine
Loss of IGs in urine.
What is nephritic-nephrotic syndrome? Pathophys? Lab findings? Specific causes? Most common?
Severe nephritic syndrome w/ GBM damage so bad it damages charge barrier leading to protein loss and other nephrotic syndrome features.
Can be caused by any nephritic disease, but usually
Diffuse proliferative GN
MPGN
What is seen in LM in acute PSGN? IF? Antibodies involved/location/type of HSR? EM? Epid? Prognosis? Presentation? Lab findings?
LM: Glomeruli enlarged and hypercellular
EM: Subenpithelial IC humps
IF: “starry sky” granular appearance “lumpy bumpy” due to IgG, IgM, and C3 deposition along GBM and mesangium
Usually in children, psost group A strep (2 weeks)
Type III HSR
Peripheral and periorbital edema, coca colored urine, hypertension
self-limiting
Incr. anti-DNAase B titers
Decr. complement levels
What is seen in LM and IF of RPGN? What is the composition? Prognosis? Causes? Findings/treatment/presentation in the specific causes?
LM/IF: Crescent moon shape consisting of fibrin and plasma proteins, with glomerular parietal cells, monocytes, macrophages
Poor prognosis. Rapidly deteriorating renal function.
CAUSES
Goodpasture-type II HSR; Abs to GBM (type IV collagen) and alveolar BM. Linear IF
Hematuria/hemoptysis
Emergent plasmapheresis
Granulamatosis w/ polyangiitis (Wegener): c-ANCA
Microscopic polyangiitis: p-ANCA
What are the causes of DPGN? What is seen on LM? EM? AB involved? Type HSR? IF?
LM: Wire looping of capillaries
EM:Sub endothelial and sometimes intramembranous IgG based ICs often w/ C3 deposition
IF:Granular
Causes: SLE (most common cause of death)or MPGN
What is seen on LM/EM/IF in IgA nephropathy? AB/Type of HSR? Causes? Presentation?
LM: Mesangial prolif.
EM: mesangial IC deposits
IF: IgA-based IC deposits in mesangium
Causes: henoch schoenlein purpura
Presentation: Renal insufficiency or acute gastroenteritis
Episodic hematuria w/ casts.
What is the pathophys of alport syndrome? Genetics? Presentation? EM?
Pathophys: Mutatin in type IV collagen leading to thinning and splitting of GBM
X=linked
Eye problems (retinopathy, lens dislocation), glomerulonephritis, sensorineural deafness
EM: Basket weave appearance
Can’t see, can’t pee, can’t hear a buzzing bee
What is the appearance of type 1 MPGN on EM? IF? LM? Causes of type 1? What are the EM findings of type II MPGN? Pathophys of type II?
Type I
LM: Tram track appearance
EM: Subendothelial immune complex deposits
granular IF
Causes: Idiopathic or secondary to HBV or HCV
Type II
Intramembranous IC deposits; “dense deposits:
C3 nephritic factor (stabilizes C3 convertase leading to decr. serum C3 levels
What its seen on LM/EM/IF in FSGS? What is deposited? Epid? Causes? Treatment? Prognosis?
LM: Segmental sclerosis and hyalinosis
EM: Effacement of foot process similar to MCD
IF: Focal deposits of IgM, C3, C1
Epid: Most common cause of nephrotic syndrome in AA and Hisp.
Treatment: Primary has inconsisten response to steroids
Prognosis: May progress to chronic kidney disease
Cause: Primary or HIV, SCD, Heroin abuse, obesity, IFN treatment, chronic kidney disease
What is seen on LM/IF/EM in minimal change disease? epid? Causes? Complications? Treatment/prognosis?
LM: Normal glomeruli (maybe lipid in PCT cells)
EM: Effacement of foot processes
IF: neg.
Causes: Often idiopathic, triggered by recent infection or immunization
Epid: Most common cause in children
Treatment: Corticosteroids (excellent response)
What is seen on LM/IF/EM in membranous nephropathy? Epid? Causes? Treatment/prognosis?
LM: Diffuse capillary and GBM thickening
EM: Spike and dome appearance w/ subepithelial deposits
IF: Granular (IC deposition)
Causes: Primary or antibodies t PLA2 receptor, NSAIDS/penicillamine, HBC/HCV, SLE, solid tumors)
Epid: Most common cause of primary nephrotic syndrome in caucasian adults
Treatment: Poor response to steroids
Prognosis: May progress to chronic renal disease
What is seen on LM in amyloidosis? Associations?
LM: Congo red stain shows apple=green birefringence under polarized light
Kidney is most commonly involved organ in system. amyloidosis
Mult. Myeloma, TB, RA
What is seen on LM of diabetic glomerulonephropathy? Pathophys?
LM: mesangial expansion, GBM thickening, Eosinophillic nodular glomerulsclerosis (Kimmelstein nodules)
Nonenzymatic glycosylation of GBM leads to thickening and incr. perm.
NEG of efferent arterioles laeds to incr. GFR and mesangial expansion.
How do kidney stones present? What are some severe complications? What is the main method of treatment/prevention?
Unilateral flank tenderness, colicky pain radiating to groin, hematuria
Hydronephrosis, pyelonephritis
Encourage fluid intake
At what pH do calcium kidney stones precipitate? In what form? x ray findings? Crystal description? Causes? Most common presentation (lab findings)? Treatment?
Incr. pH (calc phosphate)
Decr. pH (calc. oxalate)
Radioopaque
Envelope or dumbell shaped calcium oxalate
Ethylene glycol ingestion, vitamin C abuse, hypocitraturia, malabsorption (crohns)
Stone w/ hypercalciuria and normocalcemia
hydration, thiazides, citrate
At what pH do ammonium magnesium phosphate kidney stones precipitate? x ray findings? Crystal description? Causes? Most common presentation (lab findings)? Treatment?
Incr. pH
Radioopaque
Coffin lid
Struvite
Infection with urease + bugs (proteus, staph sapro, klebsiella) that hydrolyze urea to ammonia leading to urine alkalinization
Staghorn calculi
Eradication f underlying infection
Surgical removal of stone
At what pH do uric acid kidney stones precipitate? x ray findings? Crystal description? Risk factors? Imaging? Associations? Treatment?
Decr. pH
Radiolucent
rhomboid or rosettes
Decr. urine volume, arid climates, acidid pH
Visible on CT and U/S, not xray
Hyperuricemia
Diseases w/ incr. cell turnover, such as leukemia
Alkalinization of urine
Allopurinol
At what pH do cystine kidney stones precipitate? x ray findings? Crystal description? Pathophys? Epid? Possible presentation? Diagnosis? Treatment?
Decr. pH
RAdiolucent
Hexagonal
Autorecessive condition in which cystine reab PCT transporter loses function leading to cystinuria. Cystine is poorly soluble, thus forming stones
Children
Can form staghorn calculi
Sodium Cyanide Nitroprusside test
Alkalinization of urine
What is hydronephrosis? Usual cause? Other causes? Results? When does serum creat. become elevated?
Distention/dilation of renal pelvis and calyces
Urinary tract obstruction (renal stones, BPH, cervical cancer, injury to ureter)
Retroperi fibrosis, vesicoureteral reflux
Only if obstruction is bilateral
compression and possible atrophy of renal cortex and medulla
Histo of Renal cell CA? Epid? Risk factors? Presentation? Spread? treatment? Mutation? ASsociated PNP sydromes? Why is it “silent” cancer?
PCT cells become polygonal clear cells filled with accumulated lipids and carbs
Men 50-70
Smoking and obesity
Hematuria, palpable mass, secondary polycythemia, flank pain, fever, weight loss
Invades renal vein then IVC then to lung and bone
Resection if localized
Immunotherapy or targeted therapy if spread
chemo and radiation doesn’t work
Most common rimary renal malignancy
VHL (chrom. 3 deletion)
EPO, ACTH, PTHrP
Commonly presents as metastases
What is a renal oncocytoma (cell make up)? Histo? Presentation? Treatment?
Benign epithelial cell tumor (well circumscribed mass w/ central scar
Large eosino cell w/ abundant mitochondria and no peirnuclear clearing
Painless hematuria, flank pain, abdominal mass
Resected to exclude malignancy
What is another name for a wilms tumor? Epid? Cellular make up? Presentation? Mtation? What are two syndromes that it can be part of?
Nephroblastoma
Most common renal malignancy of ages 2-4
Embryonic glomerular structures
Large palpable, unilateral flank mass and/or hematuria
Loss of function mutations of TSGs WT1 or WT2 on chrom. 11
Beckwith-Wiedemann
WAGR
What are the symptoms of beckwith-wiedemann syndrome? WAGR complex?
Wilms tumor
macroglossia
organomegaly
hemihypertrophy
Wilms tumor
aniridia
genitourinary malformation
mental retardation
Epid of transitional cell CA? Location? What suggests bladder cancer? Risk factors? Histology?
Most common tumor of urinary tract system
Renal calyces, pelvis, ureters, and bladder
Painless hematuria (no casts) suggests bladder cancer
Pee SAC
Phenacetin
Smoking
Aniline Dyes
cyclophosphamide
papillary growth lined by transitional epithelium with mild nuclear atypia and pleomorphism
What is the pathophys of squamous cell CA of the bladder? Risk factors? Presentation?
Chronic irritation of urinary bladder leading to squamous metaplasia to dysplasia and squamous cell CA
Schistosoma haematobium, chronic cystitis, smoking, chornic nephrolithiasis
Painless hematuria
What is an acute bacterial cystitis? Presentation? Risk factors? Causes? Lab findings? What does sterile pyuria and negative urine cultures suggest for a cause?
UTI=inflammation of urinary bladder
Suprapubic pain, dysuria, urinary frequency, urgency
Systemic signs absent
Female, sexual intercourse, indwelling catheter, diabetes mellitus, impaired bladder emptying
E. Coli (most common)
Sapro
Klebsiella
proteus mirabilis (ammonia scent of urine)
Positive leukocyte esterase
Positive nitrites for gram neg. organisms
N. gonorrhoeae or chlamydia
What is the pathophys of acute pyelonephritis? Location? Presentation? Causes? Urine findings? CT findings? Risk factors? Complications? Treatment?
Neutrophils infiltrate renal interstitium
Cortex w/ relative sparing of glomeruli/vessels
Fevers, flank pain
Acending UTI
Hematogenous spread to kidney
WBCs in urine, possibly with casts
Striated parenchymal enhancement
Indwelling urinary catheter Urinary tract obstruction vesicoureteral reflux DM pregnancy
Chronic pyelo
renal papillary necrosis
perinephric abscess
urosepsis
Antibiotics
What is the pathophys of chronic pyelonephritis? Usual underlying cause? Histo?
recurrent episodies of acute pyelo
Vesicoureteral reflux or chronically obstructing kidney stones (a chronic predisposition)
Course, asymmetric corticomedullary scarring, blunted calyx. tubules contain eosino cats resembling thyroid tissue (thyroidization of kidney)
What is the pathophys/timetable of drug induced interstitial nephritis? Another name? Lab findings? Which drugs? Presentation?
tubulointerstitial nephritis
Acute interstitial renal inflammation
Pyuria (classically eosinophils)
Azotemia
Associated w/ fever, rash, hematuria, and flank tenderness, but can be asymptomatic
Drugs act as haptens, induce HSR leading to inflammation. 1-2 weeks after most drugs
Could be months after NSAIDs
Diuretics, penicillin derivatives, PPIs, sulfonamides, rifampin
What is diffuse cortical necrosis? Pathophys? Associations?
Acute generalized cortical infarction of both kidneys
Due to combination of vasospasm and DIC
Obstetric catastrophies
Septic shock
What is the epid. of acute tubular necrosis? Prognosis? Lab findings? What are the 3 stages like? Timetable for them? Describe the two different pathophysiologies. Histo?
Most common cause of acute kidney injury in hospitalized patients.
Often spontaneously resolves
Can be fatal, especially during initial oliguric phase
Incr. FENa (fractional excretion of sodium)
Granular (muddybrown) casts
Inciting event
Maintenance phase=oliguric; 1-3 weeks; risk of hyperkalemia, metabolic acidosis, uremia
Recovery phase=polyuric; BUN and serum creatinine fall; risk of hypokalemia
Ischemic: Secondary to decr. RBF (hypotension, shock, sepsis, hemorrhage, HF).
Death of tubular cells that may slough into tubular lumen (PCT and thick ascending limb are highly susceptible)
Nephrotoxic: Secondary to injury resulting from toxic substances (Aminoglycosides, radiocontrast agents, lead, cisplatin), crush injury (myoglobinuria), hemoglobinuria. PCT is particularly susc. to injury
Sloughed tubular cells w/i tubular lumen
What is the pathophys of renal papillary necrosis? Findings? Triggers? Associations?
Sloughing of necrotic renal papillae leading to gross hematuria and proteinuria.
Recent infection or immune stimulus
SAAD papa Sickle cell disease or trait Acute pyelonephritis Analgesics (NSAIDS) Diabetes Mellitus
How is acute kidney injury defined? What is another name for it? What is the pathophys of prerenal azotemia? Findings? What is the pathophys of intrinsic renal failure? Findings? Causes? What is the pathophys of postrenal azotemia? Causes?
Acute renal failure
Abruput decline in renal funciton as measured by incr. Cr and BUN
PRERENAL
Decr. RBF leads to decr. GFR
Na/H20 and BUN are retained by kidney to conserve V
Incr. BUN/Cr ratio
Decr. FENa
INTRINSIC
Due to ATN or ischemia/toxins; less commonly due acute glomerulonephritis
Patchy necrosis leads t debris obstructing tubule and fluid backflow acrss necrotic tubule leading to decr. GFR.
BUN is impaired
Decr. BUN/Cr ratio
POSTRENAL
Outflow obstruction (stones, BPH, neoplasia, cong. anom) Only with bilateral obstruction
Compare and contrast prerenal, intrinsic renal and postrenal acute kidney injury concerning urine osmolality, urine Na, FENa, and Serum BUN/Cr.
PRERENAL
Urine Osmol: >500
Urine Na: 20
INTRINSIC
Urine Osmol: 40 FENa: >2% Serum BUN/Cr: 40 FENa: >1%=mild; >2%=severe Serum BUN/Cr: Varies
What are the two forms of renal failure? Causes of each? What are the consequences of renal failure? What are the symptoms of Uremia?
Acute (ATN, prerenal, postrenal)
Chronic (hypertension, DM, congenital anomalies
MAD HUNGER
Meta Acid Dyslipidemia (incr. TGs) Hyperkalemia Uremia (Incr. BUN=Nausea and anorexia, pericarditis, asterixis, encephalopathy, platelet dysfunction) Na/H20 retention Growth retardation and devel. delay EPO failure (anemia) Renal Osteodystrophy
Describe the pathophys of renal osteodystrophy. Presentation?
Failure of Vit D Hydroxylation (decr. Ca absorption)
Failure to preserve Calcium (hypocalcemia)
Failure to excrete Phosphate (tissue calcifications leads to decr. Ca)
All this leads to Secondary hyperparathyroidism which causes:
Subperiosteal thinning of bones.
How does ADPKD present? Mutation? Chrom? How does death occur? Associations?
Numerous cysts causing bilateral enlarged kidneys ultimately destroying kidney parenchyma
Flank pain, hematuria, hypertension, urinary infection, progressive renal failure.
PKD1 (16) PKD2 (4)
complications of chronic kidney disease or hypertension (Incr. renin production)
Berry aneurysms, mitral valve prolapse, benign hepatic cysts
How does ARPKD present? ASsocation?
In infancy: systemic hypertension, progressive renal insufficiency and portal hypertension
Potters sequence in Utero
Congenital hepatic fibrosis
What is the pathophys of medullary cystic disease? Imaging findings? Prognosis?
Tubulointerstitial fibrosis and progressive renal insufficiency with inability to concentrate urine
Medullary cysts nt visualized
Shrunken kidneys on U/S
Poor prognosis
What are simple cysts filled with? What are they like on U/S? Prognosis? What are complex cysts like? Prognosis?
Ultrafiltrate (Anechoic on U/S). Very common; most of all renal masses. Incidental finding, asymp
Complex Cysts: Septated, enhanced, or have solid components.
Follow up or removal due to risk of RCC.
