Renal - FA Patho p582 - 592 Flashcards
where do you see RBC casts
Glomerulonephritis, malignant hypertension
where do you see WBC casts
Tubulointerstitial inflammation, acute pyelonephritis, transplant rejection.
what kind of cast do you see in nephrotic syndrome
fatty cast
Acute tubular necrosis, what cast do you see?
Granular (“muddy brown”) casts
Waxy casts is seen in
End-stage renal disease/chronic renal failure.
Hyaline casts
Nonspecific, can be a normal finding, often seen in concentrated urine samples
> 50% of glomeruli are involved
Diffuse proliferative glomerulonephritis
Thickening of glomerular basement membrane (GBM)
Membranous nephropathy
due to IgG, IgM, and C3 deposition along GBM and mesangium.
Acute post streptococcal glomerulonephritis
EM—subepithelial immune complex (IC) humps.
Acute post streptococcal glomerulonephritis
what are the presentation of Acute post streptococcal glomerulonephritis
Presents with peripheral and periorbital edema, cola-colored urine, hypertension. inc anti-DNase B titers, dec complement (C3) levels.
what type of cast is associated with Maltese cross sign
Fatty cast/oval fat bodies
“lumpy-bumpy” appearance on IF with which renal disease? What causes the lumps and bumps?
Acute poststreptococcal glomerulonephritis - granular appearance (“lumpy-bumpy”) B due to IgG, IgM, and C3 deposition along GBM and mesangium.
What type of HS rxn is Post strep GN?
HS-III
What are cresents in rapidly progressive GN made of?
Crescents consist of fibrin and plasma proteins (eg, C3b) with glomerular parietal cells, monocytes, macrophages
Type of HS and HLA # of Good Pasture?
HS -II, and HLA DR2
A vasculitis associated with Rapidly progressing GN?
Granulomatous polyangiitis, Microscopic polyangiitis
What does pauci-immune mean?
There is no Ig/C3 deposition involved.
Which GN is associated with “wire looping” of capillaries?
Diffuse Proliferative GN
Difference in deposition in Diffuse and Post strep GN and IgA nephropathy?
Diffuse has subENDOthelial and sometimes, intramembranous deposition where as Post Strep Gn has subEPIthelial deposits. IgA has mesangial deposits
Which GN is assoc with hemoptysis?
Rapidly Progressive - fun fact - most common on exam - Pick this unless proven otherwise
Most common cause of death in SLE?
Diffuse Prolif GN
IgA nephropathy assoc with what other diseases?
Henoch Schonlein, Celiac (w/ Dermatitis Herpetiformis), seen with resp/GI infections
GN + deafness (+blindness)?
Alports
Difference in IF between the GNs?
Linear - Good Pasture
Granular - PSGN (Diffuse Prolif)
Neg - Wagener’s, - PR3 ANCA Microscopic, MPA ANCA Churg strauss - eosinophilia, asthma
Difference between type I and II Membrano Prolif GN?
Type I - subendothelial immune complex seen on IF, “train track” appearence
Type II - intramembranous immune deposition of BM, “dense deposits”
MPGN is associated with which infectious disease?
Hep B and C
c3 nephritic factor is associated with which Nephritic syndrome?
MPGN, C3 nephritic factor stabilizes C3 convertase –> dec C3 levels
Which Nephrotic syndrome assoc with PLA2 - R Ab?
Membranous nephropathy
Minimal change disease can be secondary to what disease?
Hodgkin’s Lymphoma, due to cytokine mediated damage
Which two Nephrotic syndromes assoc with effacement of foot processes? So how do u know which one it is?
Minimal change disease and Focal Segmental Former = Children; Latter = adults
Populations associated with different Nephrotic syndrome?
Focal - African Americans, Latinx
Membranous - Caucasians
Secondary causes of Nephrotic syndrome?
Drugs, Diseases, Infections
Drugs - Penacillamine, NSAIDS (membranous), heroin (focal segment)
Infections - Hep B, C, syphyllis (Membranous), HIV - FSGS
Diseases - SLE, Solid tumors (colon, lung), (membranous)
Sickle cell (Focal segmental)
EM signs of Nephrotic syndromes
EM:
Minimal Change and Focal Segmental - effacement of podocyte foot processes
Membranous - spike and dome SubEPIthelial deposits
LM signs of nephrotic syndrome
Minimal change - looks Normal
Focal segmental - segmental sclerosis and hyalinosis
Membranous - diffuse capillary and GBM thickening
Diabetic GN - mesangial expansion and GBM thickening.
Apple green birefrigence under polarized light?
Amyloidosis
Pathomech of DB Glomerulonephropathy
Hyperglycemia –> nonenzymatic glycation of tissue proteins –> mesangial expansion; GBM thickening and Inc permeability.
Hyperfiltration (glomerular HTN and Inc GFR) –> glomerular hypertrophy and glomerular scarring (glomerulosclerosis) leading to further progression of nephropathy.
Most common cause of end stage kidney disease in US?
Diabetic GN
Kidney stones assoc with dec/inc PH?
Dec pH - uric acid, cysteine Inc pH - Struvite, CaPO4
Most common kidney stone
Calcium stones - calcium oxalate > calcium phosphate stones
Causes of calcium oxalate stones and Tx
ethylene glycol (antifreeze) ingestion, vitamin C abuse, hypocitraturia (associated with dec urine pH), malabsorption (eg, Crohn disease)
Tx thiazids, citrate, low sodium diet
Ammonium magnesium phosphate is assoc w. which bugs
Urease (+) - Proteus, Cryptococcus, H pylori, Ureaplasma, Nocardia, Klebsiella, S epidermidis, S saprophyticus
Which stones radiolucent/opaque?
Radiol -U -cent - Uric acid Radioopaque - Ca ones, Struvite, cysteine
How to treat uric acid stones?
alkinization of urine, allopurinol
Defect leading to cysteine kidney stones - which amino acids affected?
Cystein, Ornithine, Lysine, Arginine
Test for Cysteine stones?
Sodium cyanide nitroprusside test ⊕.
Name…that… stoneeee!
When does Creatinine rise with hydronephrosis?
If both kidneys affected, or obstruction bilat
polygonal clear cells, golden-yellow (poss) - what disease? Why the color?
RCC, yellow color due to inc lipid content (clear if more carbs)
Tell me how RCC spreads (v –> blood spread to where?)
From PCT –> Invades renal v –> IVC –> hematogenous spread –> metastasis lung, bone
RCC assoc with which chromosomal mutation?
VHL on Chr 3
Most common presentation of RCC? why?
As a lung or bone metastasis, bc invades renal v, then IVC, spread thru blood to lung or bone but can present with painless hematuria, palpable mass
RCC assoc with which paraneoplastic syndrome?
PTHrP, Ectopic EPO, ACTH, Renin
PEAR-aneoplastic
8 year old child develops respiratory infection, which resolves without antiobiotics. However, shortly thereafter, child’s mother notices his face is swelling. Takes child to Dr after his limbs started swelling and he is also gaining weight. 24hr urine - total protein of 4.2 g. Which of the following is likely elevated in patient’s serum? Albumin Cholesterol Antithrombin Creatinine Sodium
Cholesterol - Pt has minimal change disease. Often in children follows viral infection or bee sting. Nephrotic syndrome assoc with hyperlipidemia/hypercholesterolemia and is hypercoag state.
7 year old presents with nausea, fever, anorexia. He appears ill and has prominent swelling around the eyes. BP elevated, Lab show inc creatinine and BUN. Fresh urine sediment show RBC casts. Most likely outcome? Complete recovery Development of Cresenteric GN Development of Focal and segmental Glomerulosclerosis Persistent nonprogressive proteinuria steroid dependency
Choice A is correct. Pt has PSGN. Other tests shown could be inc ASO titers and dec C3, with normal C4 - bacteria activate the alternative, not classical complement pathway. Acute PGSN is benign and self limiting. Major sx resolve in 1-3 mo, and protein/hematuria resolve in 6mo. Complete resolution less likely with inc age.
65 yr old African Am male has 3-4 day history of burning sensation upon mictruition and inc urgency. Urinalysis shows white blood cells, LAP, nitrites. CBC - mild anemia. Pt reports that his father and two brothers also have anemia. To treat his UTI while considering his family Hx, which antibiotic is best choice? (Bonus - mech of action of Tx) Ciprofloxacin Erythromycin Nitrofurantoin Penicillin TMP-SMX
A is correct. Ciprofloxacin is used to treat UTI and is safe with family Hx of hemoyltic anemia due to G6PD( Is common in both Af Am and Mediterranean populations) Flouroquionolones (-) DNA replication by blocking topoisomerases Erythromycin and Penicillin are not recommended choices for UTI, as normally caused by G- bact Nitrofurantoin and TMP-SMX are oxidants and can trigger a hemolytic attack.
Diseases with low c3
SLE, Type II Membranoprolif GN, PSGN
CH50 tests for what?
screening test for total complement activity
2’ sx of RCC?
polycythemia, flank pain, fever, weight loss
large eosinophillic cells with lots of mitochondira w/o perinuclear clearing
renal oncocytoma
most common renal malignancy of childhood
Wilms tumor (age 2-4) - Nephroblastoma
malignancy that contains embryonic glomerular structures
Wilms - made of blastema, 1’ glom tubules, stromal cells
Genetic cause of WIlms?
loos of function mutation of tumor suppressor gene WT1/WT2 on Chr 11, next to PAX
Wilms assoc w. which other paths
WAGR complex—Wilms tumor, Aniridia (absence of iris), Genitourinary malformations, mental Retardation/intellectual disability (WT1 deletion)
Denys Drash
Beckwith Widermann
painless hematuria with no casts in elderly casts
bladder cancer
Which risk factors assoc with transitional cell bladder cancer?
Phenacetin, Smoking, Aniline dyes, Cyclophosphamide
Denys Drash
-Denys Drash
Wilms, early onset nephrotic syndrome (Diffuse mesangial sclerosis) , male pseudohermaphroditism (Dysgenesis of gonad)
Beckwith Wiedemann -
Wilms, macroglossia, organomegaly, hemihyperplasia, neonatal hypoglycemia
Everything is WIDEman, big tongue, big organs, hemihyperplasia (one part or half of the body is better)
Risk factors for Sq cell carcinoma of the bladder
Schistosoma heamatobium (Middle East), smoking, cystitis, chronic nephrolithiasis
=SCC
Most common causes of bact cystitis?
E. coli (MOST COMMON) Staph saprophyticus Klebsiella Proteus mirabilis
Lab findings for UTI
(+) leukocyte esterase (+) for nitrates - G- organisms
Pyelonephritis presents with which urine finding?
wbc casts in urine
sterile pyuria and neg urine cultures in UTI indicate which cause?
Nesseria or Chlamydia
which part of the kidney does acute pyelonephritis affect?
affects cortex, with relative sparing of glomeruli/vessels
why does pregnancy cause higher risk of pyelonephritis?
dec basal tone of uterus –> urine pooling –> inc risk of infection
Difference in G- org v Saprophyticus pyelonephritis?
G- org = Esterase and nitrate +
S.saprophyticus = esterase + and nitrate -
Microscopic findings in chronic pyelonephritis?
Coarse, asymmetric corticomedullary scarring, blunted calyx. Tubules can contain eosinophilic casts resembling thyroid tissue C (thyroidization of kidney)
rare grossly orange nodules that can look like tumors, damage due to granulomatous tissue w/ foamy macrophages
Xanthogranulomatous pyelonephritis
Xanthogranulomatous pyelonephritis is assoc with which organism?
Proteus
what kidney issue is assoc with obstetric issues?
diffuse cortical necross - acute gen cortical infarction of both kidneys - due to a combo of vasospasm and DIC
Associated with obstetric catastrophes (eg, abruptio placentae), septic shock.
Prerenal azotemia
Due to dec RBF (eg, hypotension) –> dec GFR. Na+/H2O and BUN retained by kidney in an attempt to conserve volume –> INC BUN/creatinine ratio (BUN is reabsorbed, creatinine is not) and DEC FENa.
Intrinsic renal failure - causes?
Generally due to acute tubular necrosis or ischemia/toxins; less commonly due to acute glomerulonephritis (eg, RPGN, hemolytic uremic syndrome) or acute interstitial nephritis.
Pathomech of renal failure in ATN, why the change in BUN/Cr ratio?
In ATN, patchy necrosis –> debris obstructing tubule and uid backflow across necrotic tubule –> DEC GFR. Urine has epithelial/granular casts. BUN reabsorption is impaired = DEC BUN/creatinine ratio and INC FENa
Postrenal azotemia
Due to out ow obstruction (stones, BPH, neoplasia, congenital anomalies). Develops only with bilateral obstruction.
Consequences of Renal Failure
Consequences (MAD HUNGER):
- Metabolic Acidosis
- Dyslipidemia (especially triglycerides)
- Hyperkalemia
- Uremia
- Na+/H2O retention (HF, pulmonary edema, hypertension)
- Growth retardation and developmental delay
- Erythropoietin failure (anemia)
- Renal osteodystrophy
Sx of Uremia
Nausea and anorexia
Pericarditis
Asterixis
Encephalopathy
Platelet dysfunction
Explain Renal osteodystrophy
Hypocalcemia, hyperphosphatemia, and failure of vitamin D hydroxylation associated with chronic kidney disease
Renal osteodystrophy lead to which endocrine issues?
2° hyperparathyroidism –> 3° hyperparathyroidism (if 2° poorly managed).
High serum phosphate can bind with Ca2+ –> tissue deposits –> DEC serum Ca2+.
Dec 1,25-(OH)2D3 –> intestinal Ca2+ absorption
Pyuria w. eosinophils and azotemia after drug admin?
Acute interstitial nephritis
Causes of Acute interstitial nephritis
- Pee (diuretics)
- Pain-free (NSAIDs)
- Penicillins and cephalosporins
- Proton pump inhibitors
- RifamPin
Most common cause of acute kidney injury in hospitalized patients.
Acute Tubular necrosis
Part of nephron most susceptible to injury with Ischemic Acute Tubular necrosis
PCT and thick ascending limb are highly susceptible to injury
Drugs and other causes that can lead to nephrotoxic acute tubular necrosis
- aminoglycosides,
- radiocontrast agents,
- lead,
- cisplatin,
- ethylene glycol
- crush injury (myoglobinuria),
- hemoglobinuria
Part of nephron most susceptible to injury with nephrotoxic acute tubular necrosis?
PCT
Types of casts seen in acute tubular necrosis, and what happens to FENa
granular casts, and Inc FENa
Sloughing of necrotic renal papillae gross hematuria and proteinuria.
Renal Papillary necrosis
Causes assoc with renal papillary necrosis
SAAD papa with papillary necrosis:
- Sickle cell disease or trait
- Acute pyelonephritis
- Analgesics (NSAIDs)
- Diabetes mellitus
Causes of renal artery stenosis - prox vs distal?
Atherosclerotic plaques—proximal 1/3rd of renal artery, usually in older males, smokers.
Fibromuscular dysplasia—distal 2/3rd of renal artery or segmental branches, usually young or middle-aged females
Complications of ADPKD?
death from complications of chronic kidney dz or HTN caused by inc renin
3 pathologic conditions associated with ADPKD?
berry aneurysms, mitral valve prolapse, benign hepatic cysts, diverticulosis
5 clinical symptoms of ADPKD?
flank pain, hematuria, HTN, urinary infection, progressive renal failure
what are 2 genes associated with ADPKD?
85%, ch 16, PKD1 15%, ch 4, PKD2
Rx for ADPKD?
ACEI/ARBs
cystic dilations of collecting ducts that often presents in infancy?
ARPKD
Cause of portal HTN in ARPKD?
is assoc w/ congenital hepatic fibrosis & hepatic cysts -> portal HTN
tubulo interstitial fibrosis and progressive renal insuff?
Autosomal dominant tubulointerstitial kidney disease - has flat true cysts - segments of collecting ducts abnormally dilated in medulla @ tips of papillae, shrunken kidneys
