PANCE Blueprint Renal System (5%)
Follow along with the NCCPA™ PANCE Renal System Content Blueprint
- 21 PANCE Renal System Content Blueprint Lessons
- GU and Renal Exam
- Renal System Pearls Flashcards
- Picmonic™ Integrated Blueprint lessons
- Content Blueprint high-yield summary tables
- ReelDx integrated video lessons
- PANCE NCCPA board review video lessons with Joe Gilboy covering acid/base and electrolyte disorder
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)
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
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)
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.