Renal Flashcards
RBC casts seen in?
Glomerulonephritis (nephritic syndrome), ischemia, or malignant hypertension
WBC casts seen in?
tubulointerstitial inflammation, acte pyelonephritis, transplant rejection
Fatty casts “oval fat bodies” seen in?
nephrotic syndrome
Granular “muddy brown” casts seen in?
Acute tubular necrosis
Waxy casts seen in?
Advanced renal disease/chronic renal failure, chronic glomerulonephritis/chronic pyelonephritis
Hyaline casts seen in?
nonsepcific, can be a normal finding, often seen in concentrated urine samples
Dysplastic Kidney?
non-inherited congenintal malformation where renal parenchyma has cysts and cartilage
What are common complications of ADPKD?
berry aneurysms, hepatic cysts, and mitral valve prolapse
What do the kidneys look like in Medullary cystic kidney disease?
cysts in teh medullary collecting ducts and parenchymal fibrosis results in shrunken kidneys and worsening renal failure
What are the different type of acute renal failure?
prerenal azotemia, postrenal azotemia, acute tubular necrosis, acute interstitial nephritis, and renal papillary necrosis
What is a common cause of prerenal azotemia?
Decreased renal blood flow (cardiac failure)
What are the lab findings in prerenal azotemia?
dec GFR, azotemia, oliguria, serum BUN:Cr ratio >15, FeNA 500mOsm/kg because there is no damage to the renal tubules
Expalin the BUN:Cr ratio in prerenal azotemia?
BUN and Cr are freely filtered, BUN is reabsorbed but Cr is not. In prerenal azotemia, low blood flow leads to inc aldosterone so increase Na and H2O reabsorption and BUN follows and gets reabsorbed
What is a common cause of postrenal azotemia?
obstruction of urinary tract downstream from kidney, ureters blocked.
Lab findings in postrenal azotemia?
Ureter blockage leads to increased hydrostatic pressure in the tubules, therefore dec GFR, azotemia and oliguria.
Early Stage: inc hydrostatic pressure pushed BUN to get reabsorbed, BUN:Cr > 15. Renal epithelium still intact so FeNa 500
Late Stage: tubular damage due to longstanding obstruction, cannot reabosrb BUN so BUN:Cr <15, FeNa>2%, urine osm <500
What is the most common cause of acute renal failure?
acute tubular necrosis aka intrarenal azotemia
Presentation of ATN?
brown granular casts in urine due to necrotic cells sloughing off and plugging the tubules. BUN:Cr<15, FENa>2%, urine osm <500
What are the two etiologies of ATN?
ischemia or nephrotoxic
Which segments of kidney are most susceptible to ischemic damage?
PCT and TAL (medullary portion)
Which segments of the kidney are most suseptible to nephrotoxic damage?
PCT (the drugs hit here first!)
What are common toxic agents to the kidney?
aminoglycosides (gentamycin), heavy metals (lead), myoglobinuria (crush injury), ethylene glycol (kids accidentally ingest and get oxalate crystals in urine), radiocontrast dye, and urate (tumor lysis syndrome in leukemia getting chemo)
How do you prevent tumor lysis syndrome?
hydration and allopurinol prior to initiation of chemo
How do you treat ATN?
dialysis until the tubular epithelium regenerates
What causes acute interstitial nephritis?
NSAIDs, penicillin, diuretics
What are defining characteristics of acute interstitial nephritis?
eosinophils in urine, oliguria, fever, rash. drug-induced hypersensitivity reaction involving intersition and tubules (infilatration of the CT between the tubules)
Common causes of renal papillary necrosis?
chronic analgesic abuse, diabetes mellitus, sickle cell trait or disease, severe acute pyelomephritis
When not idiopathic, what disease is associated with Minimal Change Disease?
Hodgkin Lymphoma
What are the common characteristics of nephrotic syndromes?
Hypoalbuminemia (pitting edema), hypogammaglobulinemia (inc risk of infection), hypercoagulable state (loss of ATIII), hyperlipidemia and hypercholesterolemia (fatty casts in the urine)
What risk factors are commonly associated with Focal Segmental Glomerulosclerosis?
HIV, heroin use, and sickle cell disease
What are the comon risk factors of Membranous Nephropathy?
Caucasian adults, assocatied with HBV or HCV, solid tumors, SLE, or drugs like NSAIDs and penicillamine
Which nephrotic syndrome has granular IF with subepithelial immune complex desposits?
Membranoue nephropathy (glomerulonephritis)
What nephritic and nephrotic syndromes is SLE associated with?
nephritic (most common): diffuse proliferative GN
nephrotic: memranous glomerulonephritis
What diseases is type I membranoproliferative glomerulonephritis associated with?
HBV, HCV
What factor is type II membranoproliferative disease associated wtih?
C3 nephritic factor–autoantibody that stabilizes C3 convertase and leads to overactivation of complement
Which 2 diseases are associated with hyaline arteriolosclerosis?
DM and benign HTN
What a Kimmelstiel-Wilson nodules pathognomonic for?
DM glomerulonephritis
Describe pathology of DM glomerulonephritis?
nonenzymatic glycosylation of vascular basememnt membrane resulting in hyaline arteriolosclerosis. Affects the efferent arteriole more than the afferent, so inc GFR and hyperfiltration injury leads to microalbuminuria.
What are the common characteristics of nephritic syndromes?
Glomerular inflammation and bleeding, limited proteinuria hypercellular, inflammed glomeruli
What are the crescents made of in RPGN?
fibrin and macrophages. C3b deposition as well
What nephritic syndrome has linear IF?
Goodpasture Syndrome
Which nephritic syndroms have granular IF?
PSGN or diffuse proliferative glomerulonephritis
What nephritic syndromes are pauci-immune?
Wegener granulomatosis, microscopic polyangiitis, and Churg-Strauss syndrome
What is c-ANCA and associated with RPGN?
Wegener’s granulomatosis
What is p-ANCA and associated with RPGN?
microscopic polyangiitis and Churg-Strauss
What are the most common causes of cystitis?
E.coli, S. saprophyticus, Klebsiella pneumoniae, proteus mirabilis, enertococcus faecalis
What is the defining feature of proteus mirabilis cystitis?
alkaline urine with ammonia scent
What bugs should be considered if you have sterile pyruia?
puria with a negative urine culture suggests Chlamydia trachomatis or neisseria gonorrhoeae causing urethritis
What are the common pathogens in pyelonephritis?
E. coli, evterococcus faecalis, klebsiella
WHat will be seen in tissue of chronic pyelonephtitis?
cortical scaring at upper and lower poles (vesicoureteral reflux), atrophic tubules containing eosinophiic proteinaceous material that resembles thyroid (thyroidization of the kidney). Waxy casts in urine
What are the most comon causes of renal failure?
DM, HTN and glomerular disease
Where is EPO made?
renal peritubular interstitial cells
What type of cancer is at increased risk if patient has chronic renal failure?
renal cell carcinoma
What do the kidneys look like of a patient who has CKD and is on dialysis?
shrunken kidney with cysts
What is the most common type of kidney stone?
calcium oxalate or calcium phosphate
How do you treat calcium oxalate stones?
hydrochlorothiazide (calcium sparing diuretic)
What type of stone has a staghorn calciculi in adults vs children?
Adults: ammonium magnesium phosphate
Children: cystine
What type of kidney stone is NOT visible on xray?
uric acid stones are radiolucent
How do you treat uric acid stones?
allopurinol (if associated with gout) or alkalininze the urine with potassium bicarb
What is the most common cause of ammonium magnesum phosphate stones?
urease-positive organisms like proteus vulgaris or Klebsiella
Which type of kidney stone is associated wtih Crohn Disease?
calcium oxalate
What kidney tumor has increased incidence in tuberous sclerosis?
angiomyolipoma–hamartoma made of blood vessels, smooth muscle, and adipose tissue
What is the classic triad of renal cell carcinoma?
Hematuria (most common), palpable mass, and flank pain
What type of paraneoplastic syndromes often present with RCC?
EPO, renin, PTHrP or ACTH
If you see a left-sided varicocle, what should you suspect?
RCC that has involved the left renal vein where it meets up wtih the left spermatic vein
What is the gross and microscopic appearance of RCC?
Gross: yeelow mass
Microscopic: clear cytoplasm (clear well type)
What tumor suppressor gene is lost in RCC?
loss of VHL (3p) tumor suppressor genes which leads to increased IGF-1 (promotes growth) and inc HIC transcription faction which increases VEFG and PDGF for angiogenesis and growth
What hereditary disease may lead to RCC?
Con Hippel-Lindau disease (also at risk for hemangioblastoma of cerebellum and RCC)
What is the major risk factor for sporadic RCC?
Smoking. typically a 60yo male with single tumor in upper pole of kidney
Lymphatically, where does RCC spread?
retroperitoneal lymph nodes
What is the most common malignante renal tumor in children?
Wilms tumor
What is WAGR syndrome?
Wilms tumor, Aniridia, Genital abnormalities, and menta and motor Retardation. Deletion of WT1 tumor suppressor gene
What is Beckwith-Wiedemann syndrome?
Wilms tumor, neonatal hypoglycemia, muscular hmihypertrophy, and organomegaly (including tongue), associated with mutations in WT2 gene cluster gene, IGF-2
Patient who smokes (naphthylamine), has been exposed to azo dyes, or long term cyclophosphamide or phenacetin use predisposes to what type of cancer?
Urothelial (transitional cell) carcinoma
Type of urothelial caricnoma that starts out high grade, early p53 mutation, then invades
Flat urothelial carcinoma
Type of urothelial carcinoma that starts out low-grade, then progresses to high grade then invades and is NOT associated wtih early p53 mutation
Papillary urothelial carcinoma
young Egyptian male with Schistosoma hematobium most likely has what type of carcinoma?
squamous cell carcinoma of the bladder
Carcinoma that arises form the urachal remannt and develop at the done of the bladder>
adenocarcinoma of the bladder
What is the most common cause of fetal hydronephrosis?
inadequate recannalization of the ureteropelvic junction (last to cannalize in the fetus)
Is there a linear or non-linear relationship between serum creatinine and GFR?
non-linear. GFR must decrease significantly for there to be an increases in serum creatinine (GFR has to reach below 60). Every time GFR halves, creatinine doubles
What is one of the most serious complicaitons of the recovery phase of ATN?
hypokalemia (massive diuresis)
