Nephrology Flashcards
R.B. is a 50-year-old woman who has been on hemodialysis (HD) for 9 years. Her medical history includes end-stage renal disease (ESRD) secondary to type 2 diabetes (DM), diabetic neuropathy, hypertension, and gastroesophageal reflux disease. She generally adheres to her dialysis prescription. Current medications include: calcium acetate 667 mg 1 capsule with meals three times a day, insulin glargine 10 units every morning and insulin aspart 3–5 units with meals, ranitidine 150 mg once daily, aspirin 81 mg once daily, renal multivitamin 1 tablet daily, gabapentin 600 mg once daily at bedtime, and atorvastatin 20 mg once daily. She receives epoetin alfa 8000 units intravenously and paricalcitol 2 mcg intravenously at each dialysis session. The patient received dietary counseling and states that she adheres to her diet as closely as possible. Her serum albumin concentration is 4.0 g/dL Her most recent laboratory values show intact parathyroid hormone (PTH) 700 pg/ mL, calcium 10.4 mg/dL, and phosphorus 6.8 mg/dL.
Which is the best recommendation for controlling
R.B.’s phosphorus concentration?
A. Increase calcium acetate to 2 capsules three times
a day.
B. Discontinue calcium acetate and initiate calcium
carbonate 1000 mg with meals and 500 mg with
snacks.
C. Discontinue calcium acetate and initiate aluminum hydroxide 1 g with meals and snacks.
D. Discontinue calcium acetate and initiate sevelamer
carbonate 1600 mg with meals three times a day
This patient’s PTH, calcium, and phosphorus values are not at goal. Answer A is incorrect because it would add more calcium load. Answer B similarly gives a calcium product to someone whose calcium concentration is too high already.
Aluminum should be avoided in patients with CKD because of the risk of aluminum intoxication (Answer C is incorrect).
Sevelamer is the best choice because it lowers phosphorus while avoiding additional calcium administration. Sevelamer dosage may have to be adjusted to reduce phosphate concentrations to goal (Answer D is correct)
Correct Answer: D
R.B. is a 50-year-old woman who has been on hemodialysis (HD) for 9 years. Her medical history includes end-stage renal disease (ESRD) secondary to type 2 diabetes (DM), diabetic neuropathy, hypertension, and gastroesophageal reflux disease. She generally adheres to her dialysis prescription. Current medications include: calcium acetate 667
mg 1 capsule with meals three times a day, insulin glargine 10 units every morning and insulin aspart 3–5 units with meals, ranitidine 150 mg once daily, aspirin 81 mg once daily, renal multivitamin 1 tablet daily, gabapentin 600 mg once daily at bedtime, and atorvastatin 20 mg once daily. She receives epoetin alfa 8000 units intravenously and paricalcitol 2 mcg intravenously at each dialysis session. The patient received dietary counseling and states that she
adheres to her diet as closely as possible. Her serum albumin concentration is 4.0 g/dL. Her most recent laboratory values show intact parathyroid hormone (PTH) 700 pg/ mL, calcium 10.4 mg/dL, and phosphorus 6.8 mg/dL.
For R.B., the nephrology team considers the addition
of cinacalcet to directly reduce the PTH concentration.
Which laboratory value is most important to monitor
for safety?
A. Liver function.
B. Calcium.
C. PTH.
D. Creatinine.
Cinacalcet is a good choice for this patient because both
the high calcium and the high phosphorus values limit the use of vitamin D analogs. However, serum calcium values should be monitored closely because hypocalcemia can occur. Hypocalcemia may lead to seizures (most likely in patients with a history of them), and/or QT prolongation (Answer B is correct). Parathyroid hormone should also be monitored because its concentration should decrease, but this is a sign of efficacy (Answer C is incorrect). Liver function tests may be performed, but serious liver problems are rare (Answer A is incorrect). Creatinine does not have to be monitored in a patient already receiving dialysis
(Answer D is incorrect).
Correct Answer: B
R.B. is a 50-year-old woman who has been on hemodialysis (HD) for 9 years. Her medical history includes end-stage renal disease (ESRD) secondary to type 2 diabetes (DM), diabetic neuropathy, hypertension, and gastroesophageal reflux disease. She generally adheres to her dialysis prescription. Current medications include: calcium acetate 667
mg 1 capsule with meals three times a day, insulin glargine 10 units every morning and insulin aspart 3–5 units with meals, ranitidine 150 mg once daily, aspirin 81 mg once daily, renal multivitamin 1 tablet daily, gabapentin 600 mg once daily at bedtime, and atorvastatin 20 mg once daily. She receives epoetin alfa 8000 units intravenously and paricalcitol 2 mcg intravenously at each dialysis session. The patient received dietary counseling and states that she
adheres to her diet as closely as possible. Her serum albumin concentration is 4.0 g/dL. Her most recent laboratory values show intact parathyroid hormone (PTH) 700 pg/ mL, calcium 10.4 mg/dL, and phosphorus 6.8 mg/dL.
R.B.’s epoetin dose has been unchanged for 6 months.
Most recently, her laboratory values were as follows:
hemoglobin 8.8 g/dL, transferrin saturation (TSAT) 14%, and serum ferritin 90 ng/mL. In the past month,
her hemoglobin concentration was 9.4 g/dL. There are
no obvious signs of infection or bleeding. Which therapeutic changes would be most appropriate to manage this patient’s anemia?
A. Administer intravenous iron sucrose 100 mg with
each dialysis session for 10 dialysis sessions.
B. Counsel the patient to take ferrous sulfate 325 mg
twice daily with meals.
C. Initiate folic acid 1 mg orally once daily.
D. Increase the epoetin dose to 10,000 units intravenously with each HD session.
This patient’s anemia has worsened while receiving epoetin therapy, most likely because of iron deficiency. Answer A is a recommended iron-loading regimen. Patients undergoing dialysis universally require parenteral iron to maintain iron stores (Answer A is correct). Oral iron is not recommended in patients receiving HD. It is unlikely to provide sufficient iron to overcome the anemia and replenish body stores (Answer B is incorrect). Folic acid is already being administered to this patient with her renal multivitamin, and it does not address the primary problem of iron deficiency (Answer C is incorrect). Although increasing the epoetin dose might increase the patient’s hemoglobin concentration minimally, it is not appropriate without first addressing the patient’s iron deficiency. In addition, it will increase dialysis-related costs with little benefit to the
patient (Answer D is incorrect).
Correct Answer: A
Which drug is most likely to be removed by high-flux
HD?
Water Molecular Volume Of
Solubility: Weight (DA): Distribution
(L/kg):
Drug A: Moderate 180 1
Drug B: High 1400 7
Drug C: High 250 0.3
Drug D: Low 300 2
A. Drug A.
B. Drug B.
C. Drug C.
D. Drug D
For a drug to be dialyzed, it should be water soluble
(Answers A and D are incorrect). In addition, drugs with relatively large volumes of distribution are not effectively removed by dialysis because the drug is in the tissues (Answer B is incorrect). With high-flux membranes, molecules of up to 20,000 Da molecular weight are removed, so molecular weight is not an issue with any of these drugs. Consequently, drug C is most likely to be removed by dialysis (Answer C is correct).
Correct Answer: C
An adult patient with stage 5 chronic kidney disease
(CKD) who is receiving maintenance automated peritoneal dialysis (PD) is experiencing abdominal pain, fever, and cloudy dialysate bags. The nephrology team suspects peritonitis and wants to initiate empiric antibiotic therapy. Which is the best empiric antibiotic
therapy for this patient?
A. Oral ciprofloxacin and metronidazole.
B. Intraperitoneal vancomycin alone.
C. Intravenous gentamicin alone.
D. Intraperitoneal cefazolin and ceftazidime.
This patient has the classic signs and symptoms of
PD-associated peritonitis. Immediate treatment is indicated.
Empiric therapy must cover both gram-positive species (Staphylococcus spp. and Streptococcus spp.) and gram-negative species (including Pseudomonas spp.). Answer D is best at covering both, and the drugs are administered by the preferred, intraperitoneal route.
Answer A uses oral medications and provides insufficient gram-positive coverage. In addition, the anaerobic coverage provided by metronidazole is not recommended for empiric treatment of PD-related peritonitis.
Answer B provides only gram-positive coverage.
Answer C is incorrect because it has inadequate gram-positive coverage and uses the intravenous route.
Correct Answer: D
A.M. is a 54-year-old man who presents with diagnosed type 2 DM. His serum creatinine (SCr) concentration is 1.6 mg/dL, and a spot albumin/creatinine ratio (ACR) is 410 mg/g. His blood pressure is 145/89 mm Hg and hemoglobin A1C (A1C) is 7.1%.
Which would provide the best therapeutic intervention at this time to slow A.M.’s diabetic kidney disease
progression?
A. Clonidine.
B. Lisinopril.
C. Metoprolol.
D. Amlodipine.
The presence of albuminuria category A2 or greater
indicates that an ACEI or ARB is beneficial to reduce
intraglomerular pressure and slow kidney disease progression (Answer B is correct). Because this patient’s blood pressure is above goal, lowering it would be beneficial. However, neither clonidine, metoprolol, nor amlodipine decrease proteinuria significantly (Answers A, C, and D are incorrect).
Correct Answer: B
A.M. is a 54-year-old man who presents with diagnosed type 2 DM. His serum creatinine (SCr) concentration is 1.6 mg/dL, and a spot albumin/creatinine ratio (ACR) is 410 mg/g. His blood pressure is 145/89 mm Hg and hemoglobin A1C (A1C) is 7.1%.
Which dietary intervention is best to reduce A.M.’s
albuminuria?
A. Protein-restricted diet.
B. Omega-3 fatty acid administration.
C. Low-carbohydrate (Atkins) diet.
D. Low-potassium diet.
Protein restriction to 0.8 g/kg/day or less will likely reduce albuminuria and is the best choice (Answer A is correct). Omega-3 fatty acids have not been studied in diabetic kidney disease (Answer B is incorrect). Atkins diet is not recommended because it tends to be a high-protein diet (Answer C is incorrect). A low-potassium diet would be appropriate for a patient with advanced kidney disease (not this patient) to prevent hyperkalemia but would not affect disease progression (Answer D is incorrect).
Correct Answer: A
A 76-year-old woman presents with an acute febrile
illness that includes diarrhea and generalized aches.
She has been taking ibuprofen for pain for the past
48 hours and presents to the emergency department
feeling “awful.” Her laboratory tests and physical
examination suggest she is not volume depleted. Her
SCr has doubled since her last visit 1 year ago. Her
physician believes she has acute kidney injury (AKI).
A urinalysis does not reveal red blood cells (RBCs),
white blood cells, or cellular casts. Which is the most
likely diagnosis in this case?
A. Prerenal AKI.
B. Hemodynamically mediated AKI.
C. Intrinsic AKI.
This is a typical presentation of hemodynamically
mediated AKI. In this case, the NSAID is inhibiting vasodilating prostaglandins in the afferent arteriole (Answer B is correct). Prerenal kidney injury refers to abrupt changes in kidney function caused by low-flow states to the kidney (e.g., hypotension; Answer A is incorrect). Intrinsic AKI includes acute tubular necrosis and acute interstitial nephritis. The presentation and a urinalysis confirming absence of cellular casts rule out this option (Answer C is incorrect). Postrenal failure is usually caused by obstruction, and there is no reason to suspect obstruction in this patient (Answer D is incorrect).
Correct Answer: B
