ABIM Certification Exam: Nephrology Division of Nephrology July - PDF document

7/9/15 ABIM Certification Exam: Nephrology Division of Nephrology July 2015 Department of Medicine UCSF CME Meyeon Park, MD MAS Assistant Professor NEPHROLOGY Disclosures Department of Medicine § I am site PI for the REPRISE study evaluating Division of efficacy of tolvaptan in autosomal dominant Nephrology polycystic kidney disease (Otsuka pharmaceuticals) 2 1

7/9/15 NEPHROLOGY Roadmap for today Department of Medicine § Acute kidney injury Division of Nephrology --------- Scheduled 15 min break------- § Glomerulonephritis § Secondary hypertension § Common electrolyte abnormalities § Acid-base § A few odds and ends 3 NEPHROLOGY Case Department of Medicine A 57-yr-old man is admitted after a motor vehicle accident. He has sustained multiple fractures and Division of Nephrology blunt chest and abdominal trauma. A left hemothorax is treated with a chest tube, an abdominal lavage reveals only minimal blood, and a noncontrast computed tomography (CT) scan of the abdomen is negative. He is volume- resuscitated with approximately 15 L of crystalloid. Twenty-four hours after admission, he is noted to have marked abdominal distension and low urine output. 2

7/9/15 NEPHROLOGY Case Department of Medicine Physical Exam: Division of Nephrology Tm 37.2 BP 135/86 HR 86 RR 16 UOP 100 cc/ 12h CVP 18 Bladder pressure 28 Intubated, sedated Decreased breath sounds at bases Regular heart sounds, no m/r/g Abdomen distended and firm, hypoactive BS NEPHROLOGY Case Department of Medicine Labs: Division of Nephrology § Na 135 § K 5.8 § Cl 103 § HCO3 24 § BUN 46 § Cr 2.3 § Imaging: Small retroperitoneal hematoma, normal sized kidneys without hydronephrosis, marked ascites. 3

7/9/15 NEPHROLOGY Case Question 1 Department of Medicine Which of the following would be the most Division of appropriate next step? Nephrology A. Abdominal decompression B. Fluid resuscitation C. Placement of bilateral ureteral stents D. Initiation of renal replacement therapy NEPHROLOGY Acute Renal Failure/Kidney Injury Department of Medicine § Pre-Renal = Decreased kidney perfusion Division of Nephrology § Intra-Renal = Intrinsic kidney disease § Post-Renal = Obstructive nephropathy 4

7/9/15 NEPHROLOGY Pre-Renal: Kidney Hypoperfusion Department of Medicine § Dehydration, overdiuresis, hypovolemia Division of Nephrology – Abdominal compartment syndrome: Typically occurs after massive volume resuscitation § Hemorrhage § Hemodynamic effect: ACE/ARB and NSAIDs § Heart failure – Cardiorenal syndrome § Cirrhosis/End-stage liver disease – Hepatorenal syndrome NEPHROLOGY Pre-Renal: Kidney Hypoperfusion Department of Medicine § Diagnosis Division of Nephrology – +/- Oliguria – High BUN:Creatinine ratio > 20 – Bland urine sediment, normal kidney US – Low FENa < 1% and low urine Na <10 mEq/L – High specific gravity, high urine osmolality – Rapid renal recovery with resuscitation § Therapy: Restore renal perfusion § Prognosis: Good, often rapid renal recovery – Exceptions: Cardiorenal and hepatorenal syndromes 5

7/9/15 NEPHROLOGY Fractional Excretion of Sodium (FeNa) Department of Medicine § percent of filtered sodium that is excreted in the Division of urine Nephrology § FeNa = (U Na * P Cr )/(P Na * U cr ) * 100 § <1% consistent with pre-renal state § Only useful when patient is oliguric (< 400 cc urine output/24 hours) § Confounded by use of diuretics NEPHROLOGY Case A 40-yr-old man with end-stage liver disease Department of Medicine secondary to alcohol abuse is admitted to the Division of hospital with altered mental status. Nephrology Home meds: Propranalol/rifaximin/lactulose/lasix/ spironolactone Physical exam: T 37.4 BP 90/50 HR 80 RR 16 O2 sat 95% RA No JVD appreciated Bibasilar rales + abdominal distension + fluid wave 1-2+ LE edema 6

7/9/15 NEPHROLOGY Case Department of Medicine Labs: Division of Nephrology § Na 135 § K 5.1 § Cl 103 § HCO3 24 § BUN 46 § Cr 2.3 § U/A: 1.025/7/neg heme/gluc/nit/LE/prot § Imaging: Normal sized kidneys without hydronephrosis, marked ascites. NEPHROLOGY Case Question 2 Department of Medicine Which of the following would be the most Division of appropriate next step? Nephrology A. Abdominal decompression B. Fluid resuscitation C. Placement of bilateral ureteral stents D. Initiation of renal replacement therapy 7

7/9/15 NEPHROLOGY Pre-renal: Hepatorenal Syndrome Department of Medicine § Severe end-stage liver disease patients Division of Nephrology § Intense renal vasoconstriction § Diagnosis of exclusion – Oliguria – Low urine sodium < 10 mEq/L, low FENa < 1% – Hyponatremia – Bland urine sediment – Normal US (no hydronephrosis) – No other identifiable cause – Lack of response to volume expansion NEPHROLOGY Pre-renal: Hepatorenal Syndrome Department of Medicine § Treatment Division of Nephrology – Splanchnic vasoconstrictors (terlipressin, ornipressin), midodrine, octreotide – TIPS (transjugular intrahepatic portosystemic shunt) – Dialysis as bridge to liver transplant – Liver transplant 8

7/9/15 NEPHROLOGY Case Department of Medicine A 39-yr-old woman with stage 4 ovarian carcinoma with bulky pelvic and retroperitoneal Division of Nephrology disease is admitted with complaints of shortness of breath and decreasing urine output. Physical exam: T 37.4, BP 130/90, HR 76, RR 16, UOP 35cc/6h + jugular venous distension Bibasilar rales + abdominal distension 1-2+ LE edema NEPHROLOGY Case Department of Medicine Labs Division of Nephrology § Na 135 § K 5.7 § Cl 107 § HCO3 16 § BUN 60 § Cr 3.1 § PO4 6.9 § Uric acid 12.4 9

7/9/15 NEPHROLOGY Case Department of Medicine Imaging Division of Nephrology § Abdominal ultrasound (outpatient study, 2 weeks ago): moderate right-sided hydronephrosis, normal left kidney § Repeat ultrasound demonstrates moderate calyceal dilation on the left, with no dilation on the right but persistent hydronephrosis. Kidney size is normal bilaterally. NEPHROLOGY Case Question 3 Department of Medicine Which of the following would be the most Division of appropriate next step? Nephrology A. CT scan with contrast B. Allopurinol and urinary alkalinization C. Emergent hemodialysis D. Percutaneous nephrostomy 10

7/9/15 NEPHROLOGY Post-Renal: Obstruction Department of Medicine § Urinary tract obstruction Division of Nephrology – Renal pelvis, ureters, bladder, prostate, urethra – Congenital and acquired lesions, BPH – Neurogenic bladder, medication effects § Nephrolithiasis § Malignancy – GI cancers – Prostate cancers – Uterine, cervical, ovarian cancers § Lymphadenopathy § Retroperitoneal fibrosis NEPHROLOGY Post-Renal: Obstruction Department of Medicine § Clinical Division of Nephrology – Oliguric or non-oliguric – Can have type 4 RTA, metabolic acidosis – Foley does not definitively rule out obstructive nephropathy – Hydronephrosis on US, although negative US does not rule out obstructive nephropathy § Therapy – Correct obstruction; can see post-obstructive diuresis from urinary concentrating defect – Urology consultation – Interventional radiology consultation: nephrostomy tubes 11

7/9/15 NEPHROLOGY Case Department of Medicine A 65 year-old woman is admitted to the hospital Division of with newly diagnosed diffuse B cell lymphoma Nephrology for induction chemotherapy. 24 hours after induction chemotherapy, she is noted to be oliguric. Physical exam T 38.4, BP 95/60, HR 94, RR 24 Heart is normal Lungs are clear, though she is mildly tachypneic Trace-1+ pitting edema NEPHROLOGY Case Department of Medicine Labs Division of § Na 138 Nephrology § K 6.0 § Cl 95 § HCO3 19 § BUN 43 mg/dL § Creatinine 3.4 mg/dL § Ionized Ca 0.79 mmol/L § PO4 9.9 mg/dL § Uric acid 11.1 mg/dL 12

7/9/15 NEPHROLOGY Case Question 4 Department of Medicine What is the most likely diagnosis? Division of Nephrology A. Rhabdomyolysis B. Tumor lysis syndrome C. Cisplatin nephrotoxicity D. Sepsis associated ATN NEPHROLOGY Intra-Renal: Acute Tubular Necrosis (ATN) Department of Medicine § Etiology Division of Nephrology – Ischemic = hypotension, sepsis, shock, hemorrhage – Toxic • Exogenous: intravascular radiocontrast, aminoglycosides, amphotericin, cisplatin, oxalate (ethylene glycol/anti-freeze ingestion) • Endogenous: rhabdomyolysis (myoglobin), hemolysis (hemoglobin), tumor lysis (urate) § Diagnosis – Muddy brown/pigmented casts in urine sediment – Elevated FENa > 1-2% – High urine Na > 20 mEq/L 13