Nephrology Flashcards
Nephrotic vs. Nephritis
NephrOtic:
- proteinuria ( > 3.5)
- edema
- hypoalbuminemia
- Oval fatty bodies ( maltase Cross) in urinalysis
- biopsy shows hypo-cellular specimen
- related to obesity—> hyperlipidemia+ edema + fatty casts/oval fatty body
NephrItic:
- proteinuria (< 3.5)
- hematuria
- HTN
Nephrotic syndrome primary etiology
- minimal change disease
- most common in children
- loss of negative charge in basement membrane promoting proteinuria (lack of charge at basement membrane) - Membranous nephropathy:
- Men > 40
- Malaria
- Medication (penicillinase) - Focal Segmental Glomerulosclerosis:
- seen with: HIV, heroin users, HTN
- most common in African American
Nephritic syndrome/ glomerulonephritis
1.IgA Nephropathy
- most common cause of acute glomerulonephritis
- most common affect young males
- occurs 24-48 hours after URI or GI infection
- Post infectious/ Post streptococcal Glomerulonephritis:
- most common after group A strep (GAS) infection
- Coca-Cola color urine
- seen in adolescent boy 2-14 years
- facial edema is common - GoodPasture’s Disease:
- Glumeronephritis + Hemoptysis
- anti-GBM antibody against the type 4 collagen of the glomerular basement membrane
Acute kidney injury —> Prerenal
- kidney is fine
- but decrease renal perfusion
- due to hypovolemia (volume depleted)—> ( diuretics, diarrhea, vomiting, dehydrated)
- other causes:
1. NSAIDS: Afferent arterial constriction
2. ACE-inhibitors: Efferent arterial dilation
Diagnosis:
- BUN/Cr ratio > 20:1
- Fractional excretion of sodium < 1%
- concentrated urine
- decrease urinary sodium < 20 (kidney are working fine, and able to retain sodium)
Treatment:
- IV fluid ( respond well !!)
Acute kidney injury —> Post-renal Azotemia
- due to obstruction (stop urine flow from kidney to bladder)—> (kidney stone, tumors, BPH, prostate, cancer)
Diagnosis:
- ultrasound —> look for sign of obstruction
Treatment:
- remove obstruction —> lithotripsy, urinary stent
Intra-renal or Intrinsic Renal Failure ( acute interstitial Nephritis, acute tubular necrosis)
- Acute Interstitial Nephritis:
caused by:
1. Medication (70%) —> NSAIDS, penicillin, Sulfa-, rifampin
2. infection, autoimmune process
clinical:
- fever, esosinophellia, rash
diagnosis:
- WBC casts ( neutrophils) seen in urinalysis
Treatment:
- remove offending agent
- Acute Tubular Necrosis:
- most common type of Intrinsic kidney injury
Caused by:
- ischemia —> prolonged prerenal azotemia
- nephrotoxic agents —> contrast dye, aminoglycosides
Diagnosis:
- Granular or muddy brown casts in urinalysis
- increase urinary sodium > 40 (kidney not working properly, unable to retain sodium)
- BUN/Cr ratio 10-15:1
Treatment:
- remove offending agent & IV fluid
Microscopic finding on Urinalysis
- Acute Glomerulonephritis or vasculitis:
- RBC Casts - Acute interstitial Nephritis or pyelonephritis:
- WBC casts - Nephrotic syndrome: ( or pre-renal azotemia)
- fatty casts or oval fat bodies - End stage renal disease:
- waxy casts
- or broad cast ( in CKD) - Interstitial nephritis
- Eosinophils - Acute Tubular necrosis (ATN)
- Muddy Brown Cast
- following a hypovolemic shock (prolonged hypotension)
- BUN/Cr ratio ( 10-15: 1)
- urine osmolality of 300-350 ( never < 300)
- urine Na > 20
- fraction excretion of Na > 2 %
Horseshoe kidney
- fusion at lower lobe of each kidney
- associated with:
1. Uritopelvic junction obstruction
2. Turner syndrome - increase risk for:
1. Pyelonephritis ( due to urinary stasis)
2. Kidney stone
3. Renal malignancy
4. Renal cell carcinoma
Clinical:
-most patients asymptomatic
Diagnosis:
- CT urography
Treatment:
- most cases require no treatment
Polycystic kidney disease
- autosomal dominant
- cyst is seen in the kidney or liver
Clinical:
- abdominal & flank pain
- increase risk for cerebral (berry) aneurysm & Mitral valve prolapse
PE:
- palpable flank mass
- HTN
Diagnosis:
- renal US
Treatment:
- increase fluid intake
- ACE-I/ARB
Chronic kidney disease (CKD)
-progressive functional decline for 3 months or more, accompanied by: proteinuria, abnormal urine, sediment, abnormal imaging
Stages of CKD:
1. Stage 1:
- GFR (>90) & proteinuria & abnormal urinalysis
- Stage 2:
- GFR (60-89) & proteinuria & abnormal urinalysis - Stage 3
- GFR (30-59) & proteinuria & abnormal urinalysis - Stage4
- GFR (15-29) & proteinuria & abnormal urinalysis - Stage 5:
- GFR (<15) indicates END stage Renal disease —> REQUIRE Dialysis
Causes:
1. Diabetic mellitus (1st)
2. HTN (2nd)
Diagnosis:
- proteinuria (24 hr urine, or albumin/Cr ratio)
- waxy cast (in urinalysis)
- renal US ( shows small kidney)
Treatment:
- treat HTN —> maintain BP < 140/90
- ACE-I or ARB in most patients
- A1C < 7
- dialysis at stage 5
Wilms tumor (Nephroblastoma)
- most commonly seen with children less than 5
Clinical:
- iris malformation ( aniridia = absence of iris)
- locked In position tumor (doesn’t cross midline of abdomen, unlike neuroblastoma of adrenal which does)
- mental retardation
- sexual malformation (hypospadias, cryptorchidism)
- palpable abdominal mass
- hematuria
- constipation
Diagnosis:
- abdominal US
Treatment:
- total nephrectomy with chemo 80-90% cure rate
Renal cell carcinoma (RCC)
- Tumor of the proximal convoluted renal tubule cells
- 95% of tumor in kidney
Risk:
- smoking, HTN, obesity, dialysis, Men
Clinical:
- Triad: hematuria + flank/abdominal pain + palpable abdominal mass
- left sided varicocele (due to the tumor blocking the left testicular vein)
- most common area of matastesis is the lung
Diagnosis:
- hypercalcemia ( tumor secrets PTHrP, which mimics primary hyperparathyroidism
- CT
Treatment:
- radical nephrectomy
Acid based disorder
Hepatorenal syndrome (HRS)
Seen in:
- seen with patients with liver cirrhosis secondary to systemic or renal hypoperfusion
- creatinine > 1.5
- urine sodium < 10
- absent of blood, protein, casts in urine
- renal function does not improve with IV fluid resuscitation
Caused by:
- splanchnic arterial dilation
Factors:
- reduce renal perfusion
- GI bleed, vomiting, sepsis, excessive diuretic use, SBP
- reduce glomerular pressure & GFR ( NSAIDs use—> constrict afferent arterioles)
Diagnosis:
- Fraction excretion of sodium < 1 % ( urine Na < 10)
- absence of tubular injury
- No RBC, protein, or granular casts in urine
- no improvement in renal function with fluid
Treatment:
- splanchnic vasoconstrictors ( midodrine, octreotide, norepinephrine)
- liver transplantation
Hyponatremia ( Na < 135 )
Caused by:
1. Increase ADH
2. Polydipsia, starvation
Clinical:
- confusion, lethargy, muscle cramps, N
Diagnosis:
- measure serum osmolality ( if the measured Sosm, is higher than calculated —> by more than 10-15 mOsm —> indicates an oxygenous osmole diluting the serum sodium.
- correct sodium in hyperglycemia ( sodium correction —> sodium decrease by 1.6 for every 100 elevation in glucose)
Dirty medicine videos nephrotic vs. nephritic
Indication of dialysis:
- Symptoms ( confusion, lethargy, N/V — severe uremic symptoms !!
- Elect. ( potassium = HYPERKALMEIA and acidosis NOT RESPONDING TO MEDICAL MANAGEMENT)
- Volume over load not responding to dieuritic
- Minimal/ No urine output
Renal biopsy is confirmative of CKD
Ratinopathy, for how long
HTN ( for how long)
1. Urine amount + frequency
2. Dysuria + hematuria
3. Have you been seen by nephrology
4. History of NSAIDS —>
5. HAVE YOU BEEN IN HOSPITAL … did they provide you with Intermascular medication
6. History of renal stone ?
7. Did you ever need dialysis before?
Contrast
- SPEP
Anemia
Leukopenia
Hyponatremia
Hypokalemia
BUN/Cr ratio > 30
- urine output decreased —> after holding diuretics
- urine sodium = 5
Microscopic finding on Urinalysis
- broad cast
- Muddy brown cast
- renal tubular necrosis (RTN) - RBC cast
- renal interstitial - WBC cast
- Fatty casts
- Eosinophils
Muddy brown cast in patient with ampho, AG, cisplatin or prolonged ischemia
- acute tubular necrosis
- treat with fluid
- avoid nephrotoxic agent ( contrast dye, ARBs, NSAID)
- DIALYSIS if needed
Protein, blood, eosinophils in urine + fever + rash + who took TM-SMX for past 1-2 weeks
- Acute interstitial nephritis
- stop offending agent
- steroid if no improvement
Army recruit or crush victim with CPK of 50 K + blood on dip, but no RBCs
- Rhabdomyolysis
- test: check K concentration on ECG
- Treat with: Bicarb ( to alkanize urine to prevent precipitation)
Enveloped shaped crystal on Urinalysis
- ethylene glycol intoxication
- Anionic gap metabolic acidosis ( AGMA)
- treat with dialysis or sodium-bicarb, if PH < 7.2