Nephrology Flashcards
What is Pre-renal Azotemia?
Decrease in renal blood flow and/ or decrease in Glomerular hydrostatic pressure
Causes of Pre-renal Azotemia?
- Hypovolemia
- Hypotension
- Renal artery stenosis/fibromuscular dysplasia
- Decreased cardiac output
- Medications that interfere with glomerular filtration (ACEIs, NSAIDs)
What is Intrinsic Renal Disease?
Damage to the renal parenchyma
Causes of Intrinsic Renal Disease?
- Glomerular Disease
- Tubular-interstitial Disease
- Vascular Disease
Causes of Glomerular Disease?
Rapidly Progressive Glomerulonephritis:
- Type I: GoodPasture
- Type 2: Post-streptococcal Glomerulonephritis, Lupus nephritis, IgA nephropathy
- Type 3: Small vessel vasculitides (Wegner’s)
Causes of Tubular-Interstitial Disease?
- Acute Tubular Necrosis: Muddy Brown Casts
(From Ischemic or Nephrotoxic Insults) - Acute Interstitial Nephritis
Causes of Vascular Disease of the kidney?
- Intrarenal Vascular Occlusion: Renal artery thrombosis, HUS/TTP
- Intrarenal Vasculitis: Small vessel vasculitis (Wegener’s)
What is Post-Renal Azotemia?
Renal failure due to urine obstruction
Causes of Urine Obstruction?
- Urethral obstruction by BPH
- Nephrolithiasis (kidney stones in urethra or impacted at bladder neck)
- Obstruction due to neoplastic invasion/extension (e.g. neoplasia of cervix, prostate, bladder)
- Bilateral obstruction of ureters (e.g.retroperitoneal fibrosis—ureters are retroperitoneal structures)
- Bilateral obstruction of kidneys (e.g.bilateral staghorn stones)
Most Common Clinical Manifestions of Acute Kidney Injury?
- Weight Gain
- Edema
- Oliguria
What type of acute renal injury has the following urine findings:
- Minimal/no Proteinemia
- Possible Hyaline Casts
- Osmolarity >500
- BUN/Cr: > 20
- Fractional Execretion of Sodium < 1%
Prerenal Azotemia
What type of acute renal injury has the following urine findings:
- Mild Proteinemia
- Pigmented Granular Casts
- Osmolarity < 350
- BUN/Cr: < 20
- Fractional Execretion of Sodium > 1%
Tubular Intrinsic Renal Disease
What type of acute renal injury has the following urine findings:
- Mild Proteinemia AND Leukocytes
- WBCs, WBC casts, RBCs, Eosinophils
- Osmolarity < 350
- BUN/Cr: < 20
- Fractional Excretion of Sodium > 1%
Acute Interstitial Nephritis
What type of acute renal injury has the following urine findings:
- Severe Proteinemia
- RBCs AND RBC casts
- Osmolarity > 500
- Fractional Excretion of Sodium < 1%
Acute Glomerulonephritis
What type of acute renal injury has the following urine findings:
- Minimal/No Proteinemia
- Crystals, RBCs, WBCs
- Osmolarlity < 350
- Fractional Excretion of Sodium > 1%
Postrenal Azotemia
Treatment for Acute Kidney Injury?
- Treat underlying cause
- Treat fluid imbalances
- Treat electrolyte imbalances
Definition of Chronic Kidney Disease?
- GFR < 60
- Urinary Albumin Excretion > 30
Causes of Chronic Kidney Disease?
- Type II Diabetes Mellitus
- Hypertension
- Chronic Glomerulonephritis
Lab Findings in Chronic Kidney Disease?
- Elevated BUN & Cr
- Increased K+& phosphate
- Decreased Na+& Ca2+
- Normochromic, normocytic anemia
- Metabolic acidosis
Therapy to reduce Proteinuria in Chronic Kidney Disease?
ACE- Inhibitors or ARBs
Therapy to treat Anemia in Chronic Kidney Disease?
Erythropoietin Stimulating Agents
Dietary Modifications in Chronic Kidney Disease?
- Low Phosphorous Diet/ Phosphorous Binders
- Vitamin D analogs-> Decrease PTH levels
- Low Potassium Diet-> Treat Hyperkalemia
- Protein Restriction (Advanced CKD)
Therapy to treat Metabolic Acidosis in CKD?
Sodium Bicarbonate
Indications of emergent dialysis?
AEIOU
- Acidosis
- Electrolyte abnormalities
- Ingestion of toxins
- Overload of fluid
- Uremia
Medications that cause Acute Interstitial Nephritis?
- Penicillin derivatives (methicillin, ampicillin)
- NSAIDs
- Allopurinol
- Sulfa-derivedDiuretics (thiazides, furosemide)
- Cephalosporins
- Proton pump inhibitors
- Sulfonamide antibiotics (sulfamethoxazole)
- Sulfasalazine (used to treat Crohn disease, UC, RA)
- Rifampin
Other toxins that cause Acute Interstitial Nephritis?
- Cadmium
- Lead
- Copper
- Mercury
- Toxins from some mushroom
Diseases/Conditions that cause Acute Interstitial Nephritis?
- Infections (Strep. Legionella)
- Sarcoidosis
- Amyloidosis
- SLE
- Myoglobinuria
- High uric acid levels
Kidney biopsy in Acute Interstitial Nephritis will show?
Infiltration of Inflammatory Cells and Tubular Cell Necrosis
Complications of Acute Interstitial Nephritis?
- Acute tubular necrosis
- Acute or chronic renal failure
- Renal papillary necrosis
Clinical Presentation of Minimal Change Disease?
Young Child w/ massive proteinuria. May have recent respiratory infection
Treatment of Minimal Change Disease?
- Oral Prednisone
Indications for a kidney biopsy to diagnose Minimal Change Disease?
- In Adults
- In Children refractory to steriods
Light and Electron Microscopy Findings in Minimal Change Disease?
- Light Microscopy: Normal
- Electron Microscopy: Effacement of Podocytes
Lab Findings in the Minimal Change Disease?
- Hyperlipidemia
- Hypoalbuminemia
- Heavy proteinuria
Risk Factors for Focal Segmental Glomerulosclerosis?
- Minority (African Americans)
- Obesity
- Sickle cell disease
- AIDS (HIV)
- IV drug abuse (heroin) andInterferon treatment
- Chronic kidney disease(secondary to congenital absence or surgical removal)
Symptoms of Nephrotic Syndrome?
- Edema
- Foamy urine
- Hypertension
- Dyspnea
Treatment for FSGS?
- Corticosteriods (Prednisone)
- Calcineurin Inhibitors (Cyclosporine, Tacrolimus)
Clinical Presentation of FSGS?
- Hyperlipidemia
- Hypoalbuminemia
- Hematuria
- High levels of proteinuria
What type of nephritic/nephrotic syndrome is associated with the following conditions?
Henoch Schönlein purpura Cirrhosis Celiac disease Inflammatory disorders (e.g. sarcoidosis and IBD)
IgA Nephropathy
Clinical Presentation of IgA Nephropathy?
- Hemoturia
- Flank Pain
- Low Grade Fever
Diagnostic test for IgA Nephropathy?
Kidney Biopsy
Light and Electron Microscopy Findings?
- Light Microscopy: Mesangial widening
- Electron Microscopy: Mesangial proliferation and Immune complexes
Urine analysis findings in IgA nephropathy?
- Hemoturia (RBCs and RBC casts)
- Proteinuria
Treatment for IgA Nephropathy?
- ACE- Inhibitors/ ARBs
- Glucocorticoids (Severe)
Causes of secondary Membranous Nephropathy?
- Hepatitis B,syphilis
- Systemic lupus erythematosus
- Solid tumors(esp.carcinomas)
Medications that cause Membranous Nephropathy?
- Penicillamine
- High-dose captopril
- NSAIDs(eg, diclofenac)
- Parenteral gold salts(eg, gold sodium thiomalate)
Urinalysis in Membranous Nephropathy?
- Nephrotic-range proteinuria
- Oval fat bodies, lipid droplets, fatty casts
- Microscopic hematuria
- Glucosuria despite normal blood glucose levels*