PANCE Blueprint Renal System (5%)
Follow along with the NCCPA™ PANCE Renal System Content Blueprint
Renal Diseases (PEARLS)
Acute Disorders (PEARLS)
Immune-mediated glomerular inflammation results in glomerular damage which results in urinary protein and RBC loss
Etiologies of acute glomerulonephritis:
- Proteinuria, HTN, azotemia, oliguria (<400 ml urine/day), hematuria (RBC casts) hallmark, edema is not as much as nephrotic syndrome
- Urinalysis: proteinuria < 3.5 grams per day, hematuria, RBC casts
- Biopsy: hypercellular, immune complex deposition
- IgA Nephropathy (Berger disease): most common cause of acute glomerulonephritis worldwide - often affects young males within days (24-48 hours) after URI or GI infection.
- Postinfectious - Group A strep: 10-14 days after infection - diagnosed with ASO titers and low serum complement.
- Membranoproliferative glomerulonephritis: due to SLE, viral hepatitis.
- Rapidly progressive glomerulonephritis - crescent formation on biopsy due to fibrin and plasma protein deposition.
- Goodpasture's syndrome: (+) anti-GBM antibodies, dx linear IgG deposits, treat with high dose steroids, plasmapheresis + cyclophosphamide.
- Vasculitis: lack of immune deposits (+) ANCA antibodies.
Glomerular damage results in increased urinary protein loss
The most common primary causes are:
- Proteinuria, hypoalbuminemia, edema, hyperlipidemia, edema is predominant feature, transudative pleural effusion
- Urinalysis: proteinuria > 3.5 grams on 24-hour urine, fatty casts, oval fat bodies
- Biopsy: hypo-cellular minimal change disease loss of podocytes on microscopy
The most common secondary causes are:
- Membranous nephropathy: most common in non-diabetic adults associated with malignancies.
- Minimal change disease: 80% of nephrotic syndrome in kids. Responds to corticosteroids.
- Focal segmental glomerulosclerosis: obese patients, heroin, and HIV black males.
- Lupus: both nephritic and nephrotic.
- Diabetes: common cause of nephrotic syndrome and subsequent renal failure.
Irritative voiding + Fever + flank Pain + nausea and vomiting + CVA tenderness
- Organism: E. coli
- Urinalysis: Bacteria and WBC casts
- Outpatient: ciprofloxacin/levofloxacin +/- ceftriaxone IM
- Inpatient: Ciprofloxacin/levofloxacin or imipenem for more severe disease
Acute renal failure (ReelDx + Lecture)
Acute tubular necrosis (ATN)
- Etiology: Kidney ischemia or toxins
- Urinalysis: Muddy brown casts. Renal tubular epithelial cells + High Urine Osmolality
- FENa > 2%
- Etiology: Immune-mediated response
- Drugs: PCN, sulfa, NSAIDs, phenytoin etc.
- Immunologic and infectious disease: strep, SLE, CMV, Sjogren's, Sarcoidosis
- Urinalysis: WBC casts and eosinophils
- Etiology: IGA Nephropathy (Berger disease), postinfectious, membranoproliferative
- Urinalysis: Oliguria, hematuria and RBC casts
Chronic kidney disease
CKD is a progression of ongoing loss of kidney function (GFR) defined as < 60 mL/min/1.73 m² or presence of kidney damage (proteinuria, glomerulonephritis or structural damage from polycystic kidney disease) for > 3 months.
- Measurement of GFR is the gold standard - The Cockcroft - Gault formula (requires age, body weight, and serum creatinine) or Modification of Diet in Renal Disease equation
- Etiology: Diabetes, hypertension, glomerulonephritis
- Findings: Fatigue, pruritus, Kussmaul respirations, asterixis (flapping tremor), muscle wasting, broad waxy casts
Congenital or structural renal disorders (PEARLS)
Horseshoe kidney, also known as renal fusion or super kidney, is a congenital disorder affecting about 1 in 500 people that is more common in men, often asymptomatic, and usually diagnosed incidentally
- Congenital disorder affecting about 1 in 600 people, more common in men
- Kidneys fuse together to form a horseshoe-shape during development in the womb
- Often asymptomatic, though persons affected by this condition may experience nausea, abdominal discomfort, kidney stone, and urinary tract infections
- The prevalence of horseshoe kidneys in females with Turner syndrome is about 15%
- Commonly diagnosed incidentally on abdominal imaging, can be confirmed with US, CT, MRI, or intravenous pyelogram
- Increased risk of renal cancer
- No treatment required, may treat complications such as UTIs or kidney stones
Urine outflow obstruction causes renal distention
Autosomal dominant genetic disorder presents as back and flank pain
- Ultrasound will demonstrate many fluid-filled cysts
- Associated with cerebral aneurysms, no cure, treatment is supportive, BP control
Narrowing of one or both of the renal arteries, most often caused by atherosclerosis or fibromuscular dysplasia.
- Renal Arteriography is Gold Standard for diagnosis
- May hear a renal artery bruit on auscultation
- Percutaneous transluminal angioplasty (PTA) plus stent placement or with surgical bypass of the stenotic segment
End Stage Renal Disease (ESRD)
End-stage renal disease (ESRD) is defined as a complete loss of kidney function for more than 3 months and is the last stage of chronic kidney disease
- Stage 5 kidney failure GFR < 15 mL/min/1.73 m2
- Low erythropoietin levels, no reticulocyte response occurs, typically a normochromic and normocytic anemia
- Treatment includes dialysis and kidney transplant
- Generally, dialysis is initiated when GFR < 10–15 mL/min
- High serum parathyroid hormone
- Low serum calcium
- High serum phosphate
- High serum potassium
- Waxy casts with very low urine flow are findings in end-stage renal disease
- Hypertension due to salt and water retention, and increased renin in response to low GFR
- Metabolic acidosis ↑ K+, ↑ phos, ↓ Na+, ↓ HCO3, ↓ Ca2+
- Pericarditis is a cardiac complication that requires urgent dialysis
- Loop diuretics are the preferred addition to the management of edema associated with hypertension due to chronic kidney disease
Acid/Base Disorders (PEARLS)
Average values "24/7 40/40"
- 24 (HCO3, base) / 7.40 (pH) / 40 (CO2, acid)
- pH < 7.35, pCO2 > 45, HCO3 > 26
- Lungs fail to excrete CO2 (Breathing too slow (holding onto CO2), pulmonary disease, neuromuscular disease, drug-induced hypoventilation - opiates, barbiturates)
- pH > 7.45, pCO2 < 35, HCO3 < 22
- Excessive elimination of CO2 (Breathing too fast (blowing of CO2), pulmonary embolism, fever, hyperthyroid, anxiety, salicylate intoxication, septicemia )
- pH <7.35, pCO2 < 35, HCO3 < 22
- Need to calculate anion gap: Anion Gap = Na – (Cl + HCO3-) = 10-16
- Increased ion gap (>16): Addition of hydrogen ions (lactic acidosis (think metformin), diabetic ketoacidosis, aspirin overdose)
- Diabetic Ketoacidosis
- Lactic Acidosis
- Ethylene Glycol
- Low anion gap (<16): Loss of bicarbonate (diarrhea, pancreatic or biliary drainage, renal tubular acidosis)
- pH > 7.45, pCO2 > 45, HCO3 > 26
- Loss of hydrogen (vomiting), bulimia, overdose of antacids, addition of bicarbonate (hyperalimentation therapy)
- Definition: serum potassium of > 5-5.5 mEq/L
- Presentation: Peaked T waves, prolonged QRS, muscle fatigue
- Treatment: Insulin, sodium bicarbonate, and glucose (drive potassium back into the cell). Calcium gluconate (antagonize effect of potassium on heart)
- Definition: serum potassium of < 3.5 mEq/L
- Presentation: Muscle cramps, constipation, flattened/inverted T waves, U waves
- Treatment: Potassium repletion - DO NOT use dextrose-containing fluids as this will stimulate insulin release and shift potassium within the cell which worsens the hypokalemia. Replace magnesium in magnesium deficiency
Hyponatremia / Hypervolemia: serum sodium of < 135 mmol/L
- Presentation: Muscle cramps and seizures
- Hypervolemic hyponatremia – CHF, nephrotic syndrome, renal failure, cirrhosis
- Euvolemic hyponatremia – SIADH (Picmonic), steroids, hypothyroid
- Hypovolemic hyponatremia – sodium loss (renal, non-renal)
- Serum Na should be corrected slowly—by ≤ 10 mEq/L over 24 h to avoid osmotic demyelination syndrome
Neoplastic Diseases of the Renal System (PEARLS)
Renal cell carcinoma (Lecture)
Classic triad of flank pain + hematuria + painless abdominal/renal mass
- Renal clear cell carcinoma is the most common type (80%)
- Transitional cell is the second most common type (20%)
- Smoking is the most significant risk factor
Wilms tumor (ReelDx + Lecture)
Child with painless, unilateral abdominal mass with no other signs of symptoms, also known as nephroblastoma.