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Topics that our residents did not perform
well on during the In-Training exam
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Diagnosis of primary hyperaldosteronism in metabolic alkalosis
Predict the composition of renal calculi in the setting of chronic UTI
Recognize the limitations of the MDRD equation in estimating GFR
Distinguish between office and home hypertension
Management of hyperphosphatemia in a patient with CKD
diagnose psychogenic polydipsia
Treat hyponatremia
Diagnose mixed acid/base disturbances
Diagnose membranous GN
Evaluate PCKD
Diagnose IgA nephropathy
Manage proteinuria in CKD
Question 1
A 45 y.o. woman is found to have a blood
pressure of 150/95 mmHg during office
visits on an intermittent basis over 3
months. Her blood pressure on two other
office visits has been found to be within
normal limits. She is in excellent health
and on no medications. Her father has a
history of hypertension.
Question 1
The physical exam is remarkable only for a blood
pressure of 150/90 mmHg. Labs including
electrolytes, BUN, creatinine and urinalysis are
normal. An ECG is normal.
Which of the following is the most appropriate next
step in the management of this patient?
a. Ambulatory BP monitoring
b. Echocardiography
c. Ongoing office follow up.
d. Start hydrochlorothiazide
Question 2
A 65 y.o. male is referred for evaluation of edema and proteinuria. He
complains of fatigue, but otherwise is asymptomatic. On exam the
BP is 150/80. There is 1+ ankle edema. Labs show hemoglobin 10
(MCV 74, RDW 20); urine protein:creatinine ratio is 4.4 mg/gm,
serum creatinine is 1 mg/dL, and cholesterol is 320 mg/dL. Serum
complement levels are normal. Urinalysis shows 3+ protein,
hyalofatty casts and oval fat bodies.
Which of the following is the most likely cause of this patient’s renal
symptoms?
A.
B.
C.
D.
E.
Minimal change glomerulopathy
FSGS
Membranous glomerulopathy
IgA nephropathy
ANCA-associated GN
Question 3
A 19 y.o. female is evaluated for sudden onset periorbital and pretibial
edema. 3 weeks ago she was diagnosed with an URI that has
since resolved. On PE the BP is 150/100. A soft S3 gallop is
present. There are crackles at both lung bases. The liver is
enlarged and tender. There is bilateral pitting pretibial edema.
There is no rash. Labs show creatinine 1.5, albumin 3.8. C3 and C4
are low. Urinalysis shows rare dysmorphic red cells and trace
protein.
Which of the following is the most likely diagnosis?
A. IgA nephropathy
B. Goodpasture's syndrome
C. ANCA vasculitis
D. Postinfectious GN
E. SLE nephritis
Question 4
A 19 y.o. female presents with a several month history of symmetric
arthralgias, Raynaud’s phenomenon, and a Coomb’s positive
hemolytic anemia. On physical exam she has a malar rash that
crosses the nasal labial folds. The heart and pulmonary exams are
unremarkable. Her abdomen is benign. There is 1 + leg edema.
Urinalysis shows red cell casts and 2+ protein. A kidney biopsy
shows immune complex focal proliferative glomerulonephritis.
Which if the following tests provides the most additional diagnostic
information?
A. Low C 3 and C4
B. Positive ANA
C. Positive ss-DNA
D. Positive anti-Smith antibody
E. Positive ds-DNA
Question 5
A 58 year old male with stage IV CKD secondary to
diabetic nephropathy presents for routine follow up.
Laboratory studies show calcium 8.2 mg/dL,
phosphorus 5.8 mg/dL, PTH 456 pg/mL, 25-OH vitamin
D 42 ng/mL, 1,25-(OH)2-vitamin D 58.
Which of the following is the most appropriate next step in
the management of this patient?
A. Start a 1,25-dihydroxy-vitamin D analogue
B. Start cinacalcet
C. Dietary phosphate restriction
D. Phosphate binder therapy
E. Parathyroidectomy
Question 6
A 38 y.o. man with a history of chronic liver disease secondary to hepatitis C is
treated with a 24-wk course of pegalated IFN combined with ribavarin.
Four weeks after completing treatment he complains of proximal muscle
weakness. On PE the BP is 120/80, pulse 110, RR 18. His general exam
is unremarkable. On neurologic exam he has symmetric proximal
weakness 3/5. Labs show Na 142, K 2.1, Cl 104, HCO3 20, creat 1. Urine
Na 96, urine K 10, urine Cl 110, urine osm 585.
Which of the following is the most likely diagnosis?
A.
B.
C.
D.
E.
Distal renal tubular acidosis (type I)
Vomiting
Diuretic abuse
IFN complication
Hypomagnesemnia
Question 7
A 45-yr-old previously healthy woman who weighs 50 kg undergoes surgery for a
ruptured ovarian cyst. During surgery, she is given 2 L of lactated Ringer solution,
and she is given 5% dextrose in 0.45% NaCl with 20 mEq/L KCl at 250 ml/h
postoperatively. Forty-eight hours after surgery, she complains of headache and
vomiting. BP is 140/80 mmHg. She is alert and oriented, and the general physical
and neurologic examinations are unremarkable. Laboratory data reveal the
following: Serum Na 115 mEq/L, plasma osmolality 241 mOsm/kg H2O, and urine
osmolality 850 mOsm/kg H2O. The patient is not taking anything by mouth.
In addition to stopping the 5% dextrose in 0.45% NaCl infusion, which ONE of the
following would be the MOST appropriate treatment?
A.
B.
C.
D.
5% dextrose in 0.9% saline with 20 mEq KCl at 250 ml/h
5% dextrose in 0.9% saline with 20 mEq KCl at 50 ml/h
3% saline at 100 ml/h plus intravenous furosemide until serum sodium
concentration is 132 mEq/L
3% saline at 50 ml/h plus intravenous furosemide until the serum sodium is 120
mEq/L
Treatment of Severe and Moderate
Symptoms in SIADH
Treatment
Goals of Therapy
General
• Discontinue
contributing
medications
• Fluid
restriction
Specific
Severe
•3% saline
•Furosemide
• Until symptoms
resolve
• ~10 mEq/L in 24
• ~18 mEq/L in 48
Moderate
•3% saline
•Furosemide
•?Vaptans
• Until symptoms
resolve
• <10 mEq/L in 24
• <18 mEq/L in 48
Treatment of Symptomatic
Hyponatremia
• Do not use equations
• Start 3% saline at 1 ml/kg/hr-this will increase
the plasma sodium on average by 1 mEq/L/hr
• Monitor the patient
– Measure the plasma sodium every hour initially
– Stop therapy when symptoms resolve
– Rise in plasma Na of about 5 mEq/L usually sufficient
• Treat in ICU or step-down setting
Question 8
A 45 year old Caucasian male is referred for further evaluation of
a persistent elevation in the serum creatinine of 1.4 mg/dL.
The physical exam show a blood pressure of 130/80 mmHg
and is otherwise unremarkable. The urinalysis is normal.
The estimated GFR is 56 ml/min per the MDRD equation.
Renal ultrasound shows the right kidney 11.2 cm in size and
the left kidney 10.9 cm in size. The urine protein:creatinine
ratio returns at 0.056.
Which of the following is the most appropriate step in this
patient’s management?
A. Start enalapril
B. 24 hour urine for creatinine clearance
C. Start a thiazide diuretic
D. No further evaluation
Key Points
• The estimated GFR should be calculated using the
MDRD equation whenever a serum creatinine is
measured in steady state conditions for patients with
an eGFR < 60 ml/min.
• The MDRD eGFR can be falsely low in individuals
with large muscle mass and near normal GFRs.
• Consider 24 hour urine collections for creatinine
clearance in the following populations:
–
–
–
–
–
Near normal GFR
Extremes of age and weight
Amputees
Pregnant women
Cirrhotics
Question 9
A 46 y.o. male is hospitalized for severe necrotizing pancreatitis. He is placed on NG
suction and over the first 24 hours of hospitalization he receives 6 liters of NS and
then NS at 100 mL/hour. Over the next 24 hours his urine output increases to > 3
liters per day and his plasma sodium concentration rises from 145 meq/L on
admission to 153 meq/L.
On exam the blood pressure is 140/90. Chest is clear . There is no edema.
Labs show sodium 153, potassium 3, chloride 112, bicarbonate 24, BUN 49, creatinine
1.1, urine sodium 50, urine potassium 20, urine osmolality 500 mosm/kg.
Which of the following is the most likely cause of this patient’s polyuria?
A.
B.
C.
D.
Central diabetes insipidus
Nephrogenic diabetes insipidus
Post obstructive diuresis
Solute diuresis
Polyuria
• Urine output exceeding 3 L per day
• Etiology
– Water diuresis
• diabetes insipidus
– central
– nephrogenic
• primary polydipsia
– Solute diuresis
Evaluation of Polyuria
Urine Osmolality
< 250 mosm/kg
Water Diuresis
> 300 mosm/kg
Solute Diuresis
Urine and Plasma Osmolality
in Disorders of Water Balance
1000
Normal
Water
Deprivation
dDAVP
800
Primary polydipsia
600
Central DI
400
Nephrogenic DI
200
280
285
290
295
Posm(mosm/kg)
300
Question 10
A 56 year old female presents with a 2 day history of
weakness. On physical exam she is diffusely weak
and is unable to sit up. The blood pressure is 160/95
mmHg. There is no edema.
140 96 20
1.9 32 1.4
Urine [Na+] = 75 mEq/L
Urine [Cl-] = 100 mEq/L
FeK = 20%
Which of the following is the most likely diagnosis?
A.
B.
C.
D.
Vomiting
Gordon syndrome
Hyperaldosteronism
Gitelman syndrome
Metabolic Alkalosis
BP
Volume status
BP Normal or Low
 Effective circulating volume
Loss of HCl
Loss of Volume (Na+/H20)
Loss of Gastric secretions
(vomiting, NG suction)
Diuretics
Bartter syndrome
Gitelman syndrome
BP High
 ECF
Primary
Hyperaldosteronism
Metabolic Alkalosis: Loss of Gastric
Secretions-Maintenance Phase
Volume Contraction
Reabsorption of sodium,
chloride, and bicarbonate
along the nephron
Secondary increase
in aldosterone
Metabolic alkalosis
Paradoxical
aciduria
Elimination of sodium,
chloride, and bicarbonate
from the urine
Increased H+
Excretion
Variation in Urine Electrolytes in
Vomiting
Phase
[Na+]
mEq/L
[K+]
mEq/L
[Cl-]
mEq/L
[HCO3-]
mEq/L
pH
Units
Generation
>15
>15
<15
>15
>6.5
Maintenance
<15
Variable
<15
<15
<5.5
Metabolic Alkalosis: Primary
Hyperaldosteronism
Increased
Aldosterone
Sodium
Retention
Volume Expansion
•Starling Forces in Proximal tubule
•Atrial Natriuretic Peptide
•Down regulation of NaCl CT in DCT
Natriuresis
Hypertension
Mean arterial
Pressure
Aldosterone Escape
Aldosterone
110
100
90
ECF Vol
(L)
21
18
15
20
15
10
Na+
balance
200
0
-200
Days 2
4
6
8
10
12
14
16
18
Urine Na+ and Cl- in the
Differential Diagnosis of Metabolic
Alkalosis and Hypokalemia
Condition
Vomiting
Alkaline urine
Acidic urine
Diuretic
Drug active
Remote use
Hyperaldosteronism
Urine Electrolytes
Na+
Cl(meq/L)
>15
<15
<15
<15
>15
<15
>15
<15
>15
>15
Question 11
A 42 y.o. female is evaluated for minimal edema and a urinary protein excretion
of 5 gm/24 hours. As a child she had frequent urinary tract infections and
underwent a surgical procedure to reimplant the ureters to prevent reflux.
On PE the BP is 140/95. There is trace peripheral edema. Labs show
creatinine 1.5, albumin 3.4, Urinalysis shows 3 + protein and oval fat
bodies.
Chest x-ray is normal. Renal US shows a normal left kidney and the right
kidney small and difficult to visualize.
Which of the following is the most likely cause of the proteinuria?
A.
B.
C.
D.
Minimal change disease
Membranous nephropathy
FSGS
Membranoproliferative GN
Question 12
A homeless man is discovered unconscious in the park and is brought to the emergency
department. He wreaks of alcohol, is unkempt, and is incoherent. Physical
examination shows a BP of 90/50 mmHg, heart rate of 120 bpm, temperature of
39°C, slight scleral icterus and dullness, and bronchial breath sounds over the right
lower lung fields. Laboratory data reveal the following: Serum Na 131 mEq/L, K 2.9
mEq/L, Cl 70 mEq/L, CO2 21 mEq/L, blood urea nitrogen 34, creatinine 1.4 mg/dl,
glucose 240 mg/dl, serum osmolality 320 mOsm/kg H2O, serum ketones weakly
positive, pH 7.53, PaCO2 25 mmHg, PaO2 60 mmHg, and serum albumin 3.8 g/dl.
Which ONE of the following choices BEST describes his acid-base disturbance?
A.
B.
C.
D.
E.
Metabolic acidosis
Respiratory alkalosis
Metabolic acidosis and respiratory alkalosis
Metabolic acidosis and metabolic alkalosis
Metabolic acidosis, metabolic alkalosis, and respiratory alkalosis
Question 13
23-year-old Caucasian female referred for further evaluation of hypokalemic acidosis.
She was in her usual state of excellent health with normal growth and development
until her second month of pregnancy. She had a spontaneous miscarriage, and was
found to have a serum potassium of 3.2 mEq/L and a bicarbonate level of 19
mEq/L during a hospitalization for a D and C. She was treated with oral potassium
and bicarbonate supplements and then weaned these off after 4 months of therapy.
Six weeks later, she developed myalgias and collapsed due to profound weakness.
She was found to have a serum bicarbonate level of 14 mEq/L with a serum
potassium of 1.9 mEq/L.
140 114 13 Calcium 9.1
1.9 14 1 Phosphorus 3.5
ABG-pH 7.29, PCO2 30, pO2 100
Urine K 46 Urine Na 36 Urine Cl 42 Urine Osm 580
UA ph 6.8 trace protein No casts 10-15 white cells per high power field
Which of the following is the correct diagnosis?
A.
Type IV RTA
B.
Diarrhea
C.
Type I RTA
D.
Renal tubular alkalosis
E.
Proximal RTA
Practical Approach
(Hyperchloremic metabolic acidosis)
Urinary Anion Gap
Negative
Positive
Type 2 RTA
Diarrhea
DKA/Toluene
HCl (Hyperalimentation)
Urine pH and Plasma K
Urine pH < 5.5, K 
Urine pH > 5.5, K nl/low
Urine pH > 5.5, K 
Type 4
Type 1 (secretory defect
or back-leak)
Type 1 (voltage)
Type I Classic Distal RTA-Mechanism 1
Tubular lumen Na+
Na+
Peritubular
Capillary
3Na+
ATPase
(-)
(-)
K+
K+ Wasting
ClUrine pH > 5.5
Ca-P stones
H 2O
(-)
R-Aldo
3Na+
ATPase
T
2K+
OH- + CO2 HCO3-
K+
(-)
H+
ATPase
2K+ H+
Retention
Cl-
ATPase
H+
Type I Classic Distal RTA-Mechanism 2
Tubular lumen Na+
Na+
Peritubular
Capillary
3Na+
ATPase
(-)
(-)
K+
K+ Wasting
ClUrine pH > 5.5
Ca-P stones
H 2O
(-)
R-Aldo
3Na+
ATPase
T
2K+
OH- + CO2 HCO3-
K+
(-)
H+
ATPase
2K+ H+
Retention
Cl-
ATPase
H+
Type I Distal RTA-Mechanism 3
Tubular lumen Na+
Na+
Peritubular
Capillary
3Na+
ATPase
(-)
(-)
K+
K+ Wasting
ClUrine pH > 5.5
H+
Ca-P stones
R-Aldo
Backleak of H+
H+
ATPase
H 2O
(-)
OH- + CO2
K+
(-)
2K+
3Na+
ATPase
T
2K+
HCO3Cl-
ATPase
H+
H+
Retention
Question 14
A 17-yr-old girl complains of profound weakness, dizziness, and polyuria. She
is taking no medications and has no gastrointestinal complaints. Pertinent
clinical finding is BP of 90/50 mmHg with orthostatic dizziness. Laboratory
data reveal the following: Na 140 mEq/L, K 2.5 mEq/L, Cl 100 mEq/L, CO2
33 mEq/L, blood urea nitrogen 25 mg/dl, and creatinine 0.7 mg/dl. A 24-h
urine collection reveals the following: Sodium 90 mEq, potassium 60 mEq,
Cl 110 mEq, and calcium 280 mg. Plasma renin and aldosterone are
elevated.
These findings are MOST suggestive of which ONE of the following?
A.
B.
C.
D.
E.
Adrenal adenoma
Gitelman syndrome
Bartter syndrome
Licorice ingestion
Surreptitious vomiting
Urine Na+ and Cl- in the
Differential Diagnosis of Metabolic
Alkalosis and Hypokalemia
Condition
Vomiting
Alkaline urine
Acidic urine
Diuretic
Drug active
Remote use
Hyperaldosteronism
Urine Electrolytes
Na+
Cl(meq/L)
>15
<15
<15
<15
>15
<15
>15
<15
>15
>15
Question 15
A 72-yr-old woman who has multiple sclerosis and weighs 50 kg
receives 400 mg/kg intravenous immunoglobulin infused for 3 h. At
the end of the infusion, she has an acute and dramatic worsening of
neurologic symptoms. She is suddenly unable to bear weight or
coordinate arm and leg movements and describes paresthesias and
hyposthesias of all extremities. Blood chemistries are normal except
for a serum sodium of 130 mEq/L and a plasma osmolality of 300
mOsm/kg.
Which ONE of the following is the BEST treatment for this patient?
A. 3% saline in 50-ml bolus
B. 3% saline in 150-ml bolus
C. 3% saline at 50 ml/h for 4 h
D. 0.9% saline, 1000 ml, infused as rapidly as possible with furosemide
80 mg intravenously
E. Make patient n.p.o. and observe
Question 16
A 49 y.o. female is admitted to the hospital because of severe right sided abdominal pain
requiring administration of narcotic analgesics. The patient is unable to provide a
complete medical history, but reports that she has had seizures for as long as she
can remember.
Physical exam reveals papular skin lesions in the malar area. Bilateral flank masses are
noted. There is a 2-cm periungual nodular lesion on the right great toe.
Hematocrit is 25%. Serum creatinine is 5.5 mg/dL. CT of the abdomen without contrast
reveals enlarged kidneys with bilateral renal cysts of varying size in the cortex and
the medulla; several variably sized masses with densities identical to perinephric fat
are also detected in areas not involved with cysts.
Which if the following is the most likely diagnosis?
A. ADPCKD
B. Von Hippel-Lindau disease
C. Medullary cystic kidney disease
D. Tuberous sclerosis
E. Bilateral renal dysplasia
Question 17
A 66-year-old man comes for a follow-up
examination for elevated blood pressure.
1 week ago
He has a history of chronic kidney
disease and hypertension well controlled
Potassium
4.5 meq/L
with hydrochlorothiazide. One week
ago, he was evaluated in the office after
Creatinine
1.2 mg/dL
obtaining several home blood pressure
Urine
measurements averaging 145/90 mm
albumin:creatinine
Hg. Enalapril was added at that time.
200 mg/g
ratio
He has felt well and has no history of
cough, lower-extremity edema, or
dyspnea. He also takes low-dose
aspirin.
On physical examination today, temperature is
normal, blood pressure is 126/70 mm
Hg, respiration rate is 18/min, and pulse
rate is 78/min and regular. On cardiac
examination, the point of maximal
impulse is laterally displaced and an S4
gallop is heard. There is no edema.
In addition to dietary potassium restriction, which of the following is the most
appropriate next step in this patient’s management?
A.
B.
C.
D.
Add diltiazem
Discontinue enalapril; switch to metoprolol
Repeat creatinine and potassium measurement in 1 week
Kidney arteriography
Today
5.2 meq/L
1.5 mg/dL
Question 18
78-year-old female with a history of longstanding type II
diabetes mellitus, hypertension, Takotsubo
cardiomyopathy with an EF of 38%, and stage III CKD is
seen for routine follow up. From a symptomatic
standpoint she was doing well without complaints of
chest pain, PND or orthopnea. She has a history of
hyperkalemia while on ACE inhibitors, and her heart
failure has been managed with hydralazine, furosemide,
isosorbide dinitrate, and metoprolol.
BP 128/72, pulse 53/min. No JVD. Chest is clear. Cardiac
exam shows bradycardia and a I/VI systolic murmur
heard along the left sternal border. No edema.
Question 18
Lab
Result
Sodium
141
Potassium
6.6
Calcium
9.8
Chloride
104
Phosphorus
4.2
Bicarbonate
26
Glucose
131
BUN
66
Hemoglobin
9.6
Creatinine
eGFR
1.55
39
Lab
Urine protein:creatinine
ratio
Urinalysis Specific gravity 1.014, pH 5.5, 1+ protein.
No cells. Few fine granular casts.
Result
0.486
Question 18
Which of the following is the most important
factor in the pathogenesis of the
hyperkalemia?
A. Decreased GFR
B. Volume depletion
C. Hyporeninemic hypoaldosteronism
D. Redistribution of potassium from cells to
the extracellular fluid space
Which Patients are at Risk for
Hyperkalemia?
•
•
•
•
•
•
•
eGFR < 30 ml/min
Diabetes mellitus
Human immunodeficiency virus infection
Congestive heart failure
Older adults
Dietary indiscretion
Medications
Evaluation of Hyperkalemia
K> 5.5
Exclude laboratory error
• Hemolysis
• Excessive tourniquet time
• Severe leukocytosis or
thrombocytosis
Redistribution
• Tissue injury (rhabdomyolysis,
tumor lysis, hemolysis, GI bleed)
• Insulin deficiency
• Metabolic acidosis
• Hyperosmolarity
• Drugs (digoxin toxicity)
• Hyperkalemia periodic paralysis
Decreased renal excretion
Renal failure
GFR < 20 ml/min
Decreased urine flow
Severe hypovolemia
Hyperkalemia distal RTA
Causes of Hyperkalemic Distal Renal
Tubular Acidosis
Palmer B. N Engl J Med 2004;351:585-592
Causes of Hyperkalemic Distal
Renal Tubular Acidosis
Hypoaldosteronism
Low renin
• Medications
 NSAIDs
 Cox-2 inhibitors
 Calcineurin inhibitors
 Beta-blockers
• Diabetes mellitus
• HIV infection
High renin
• Adrenal insufficiency
• Congenital enzyme
defects
• Medications
• ACE inhibitors
• ARBs
• Heparin
• Ketoconazole
Collecting Duct Defects
• Medications
• Amiloride
• Triamterene
• Spironolactone
• Eplerenone
• Trimethoprim
• Pentamidine
• Tubulointerstitial disease
• Urinary tract obstruction
• Defective MR receptor
Hyperkalemia: Key Points
• After excluding redistribution and laboratory error,
decreased renal excretion of potassium is the most
common cause of hyperkalemia
– Drugs, collecting duct defects, and hyporeninemic
hypoaldosteronism are the most common causes
• Therapy of hyperkalemia associated with hyporeninemic
hypoaldosteronism includes:
–
–
–
–
Modify contributing medications
Dietary potassium restriction (~3000 mg per day or 60 mEq)
Diuretics
Sodium polystyrene
Question 19
A 26 year old female presents with a history of intermittent tea-colored
urine, often becoming apparent a day or two after onset on upper
respiratory tract infections. On exam the blood pressure is 140/90
mmHg, heart and lungs normal, and there is no peripheral edema.
There is no rash or synovitis.
Urinalysis reveals trace protein and 5-10 dysmorphic red cells per high
power field. The serum creatinine concentration is 0.6 mg/dL. Antinuclear antibodies and anti-neutrophil antibodies return negative.
Serum complement levels are normal.
Which one of the following represents the most likely diagnosis?
A.
B.
C.
D.
membranoproliferative glomerulonephritis
membranous nephropathy
IgA nephropathy
post-infectious glomerulonephritis
Question 20
A 49-year-old white female who has a
history of T12 paraplegia secondary to
spinal cord injury and neurogenic bladder
presents with gross hematuria. On
physical exam there is left flank pain.
Urinalysis shows pH 7.4, 2+ leukocyte
esterase, 1+ nitrite, 15-20 white cells per
hpf, and 1 + bacturia.
Question 20-KUB
Question 20
Analysis of the fragments of the patient’s
stones is likely to reveal which one of the
following components?
A. Calcium oxalate
B. Calcium phosphate
C. Cystine
D. Magnesium ammonium phosphate
E. Uric acid
Question 21
A 65 year old man presents for follow up after presenting with a left leg
deep venous thrombosis 3 weeks ago. He was treated with low
molecular weight heparin followed by warfarin. He has been in
good health, and has a remote 30 pack year history of smoking. His
physical exam demonstrates increased non-pitting edema in the left
lower leg.
Laboratory studies show a serum creatinine of 1.4 and normal
complete blood count. INR is 2.2. Urinalysis shows trace protein
and 1+ blood with 5 red cells per high power field. The urine
protein:creatinine ratio is 0.349.
Further chart review show that a urine dipstick performed 6 months ago
showed 1+ blood and trace protein.
Which of the following is the most appropriate next step in the patient’s
management?
A. Discontinue warfarin
B. Kidney biopsy
C. Ciprofloxacin
D. Cystoscopy
Urinary Albumin-Total Protein Ratio in
Distinguishing Between Glomerular and
Non-glomerular Hematuria
A value > 0.59 suggest glomerular hematuria
Am J Kidney Dis 2008; 52:235-241
Question 22
A 50-yr-old man with hemophilia complicated by HIV/AIDS and cirrhosis caused by
hepatitis C is admitted for renal failure. He is treated with furosemide and
spironolactone for management of ascites and sulfamethoxazole and trimethoprim for
prophylaxis against Pneumocystis jiroveci pneumonia. There is no history of
alcoholism. On admission, BP is 98/62 mmHg, and physical examination shows
scleral icterus, stigmata of cirrhosis, an abdominal fluid wave, and pitting edema of
his lower extremities. He is alert and oriented but has asterixis.
Laboratory data show serum Na 128 mEq/L, K 5.7 mEq/L, Cl 95 mEq/L, CO2 23 mEq/L,
BUN 49 mg/dl, glucose 110 mg/dl, and creatinine 2.3 mg/dl, and plasma osmolality
290 mOsm/kg. Urine osmolality is 580 mOsm/kg. Other laboratory values included
urine Na 53 mEq/L, random cortisol 25 g/dl, uric acid 14.2 mg/dl, serum triglycerides
50 mg/dl, total cholesterol 95 mg/dl, total protein11.7 gm/dl, and albumin 2.4 gm/dl.
Which ONE of the following is the MOST likely cause of the patient’s
hyponatremia?
A. Addison disease
B. Trimethroprim therapy
C. Syndrome of inappropriate antidiuretic hormone secretion (SIADH)
D. Pseudohyponatremia
Question 23
A 46-year-old woman comes to the emergency department because of new-onset seizures. During
physical examination, she is slightly confused. Blood pressure is 136/80 mm Hg. No neurologic
abnormalities are noted, and other physical findings are normal.
Laboratory studies:
Serum creatinine 1.6 mg/dL
Serum electrolytes Sodium 140mEq/L Potassium 4.8 mEq/L Bicarbonate 22 mEq/L Serum albumin
4.6 g/dL Serum calcium 9.1 mg/dL Serum magnesium 1.8 mEq/ L Serum phosphorus 4.8 mg/dL
Gadolinium-enhanced magnetic resonance imaging (MRI) of the head is performed, and the patient is
admitted to the hospital. Repeat laboratory studies obtained 90 minutes after the MRI are shown
below.
Serum sodium 139 mEq/L Serum potassium 4.9 mEq/L Serum bicarbonate 21 mEq/L Serum calcium
6.2 mg/dL.
Which of the following is most appropriate at this time?
(A) No treatment is indicated
(B) Administer 10% calcium gluconate, 10 mL intravenously over a five-minute period
(C) Administer magnesium sulfate, 2 g intravenously over a 20-minute period
(D) Initiate hemodialysis using a high calcium dialysate
(E) Start calcium carbonate, 100 mg orally daily, and calcitriol, 0.25 μg orally daily
Question 24
A previously healthy 27-year-old woman who is running a marathon
collapses as she approaches the 25-mile marker and is rushed to
the medical tent. During physical examination, she is barely
arousable. Pulse rate is 110 per minute, and blood pressure is
96/65 mm Hg. The skin is dry. Crackles are audible at the lung
bases. Other physical findings are normal. There are no facilities for
measuring the patient's serum sodium level.
An intravenous catheter is inserted.
Which of the following is the most appropriate initial intravenous fluid
therapy for this patient?
(A) 0.45% sodium chloride, 500 mL
(B) 0.9% sodium chloride, 500 mL
(C) 3.0% sodium chloride, 100 mL
Question 25
A 36-year-old man is found to have a serum creatinine level of 4.2 mg/dL during routine preemployment evaluation. He reports no symptoms except for frequent episodes of gout over the
past 19 years and three-times-nightly nocturia. Two of his four younger siblings have had gout; he
does not know the status of their kidney function. His mother is healthy; he has lost contact with
his father.
Blood pressure is 110/70 mm Hg. Laboratory studies disclose hyperuricemia that is associated with no
other abnormalities except for mild metabolic acidosis and elevated serum creatinine; other
laboratory findings are shown below.
Hematocrit 34% Hemoglobin 10.2 g/dL Urinalysis Specific gravity, 1.006; protein trace; 0-2 RBCs,1-3
WBCs/hpf
Ultrasonography reveals 9-cm echogenic kidneys with several small peripelvic cysts bilaterally.
Which of the following is the most likely diagnosis?
(A) Autosomal dominant polycystic kidney disease
(B) Autosomal recessive polycystic kidney disease
(C) Medullary cystic kidney disease, type 2
(D) Medullary sponge kidney
(E) Tuberous sclerosis