nephrology: challenging cases copyright...conflict of interest disclosure i disclose the following...
TRANSCRIPT
Nephrology: Challenging Cases
UPDATE IN INTERNAL
MEDICINE - 2019
Robert S. Brown, M.D.
COPYRIGHT
Conflict of Interest Disclosure
I disclose the following relevant financial relationship:
Börm Bruckmeier Publishing LLC −− Author
“Nephrology Pocket” and “Acid Base Electrolytes Pocket” book & apps
COPYRIGHT
Acid Base & Electrolyte
Disorders
COPYRIGHT
1) A 51 yo woman with relapsed acute
myelogenous leukemia (AML) and an IV line
infection is seen for hyperkalemia.
She was noted to lose weight (52→50 Kg) and
have orthostasis and tachycardia despite omission
of all antihypertensive Rx.
Medications: Daptomycin, cefepime, allopurinol,
megestrol, odansetron (decitabine & hydrea for ↑
blasts 10 days ago)
COPYRIGHT
Laboratory studies reveal the following:
Sodium (mEq/L) 131
Potassium (mEq/L) 6.2
Chloride (mEq/L) 103
Bicarbonate (mEq/L) 20
BUN (mg/dL) 34 (12 mmol/L)
Creatinine (mg/dL) 0.8 (71 µmol/L)
Uric acid (mg/dL) 1.8 (107 µmol/L)
UNa+ (mEq/L) 77
UK+ (mEq/L) 33
Ucreat (mg/dL) 72 (6.36 mmol/L)
UOsm (mOsm/L) 664
Px exam: Cachectic, BP 120/72 →100/60, T 35° C
COPYRIGHT
The hyperkalemia is likely secondary to
A. Volume depletion from hydrea
B. Sepsis
C. Salt-wasting renal disease from AML
D. Decitabine toxicity
E. Megestrol toxicityCOPYRIGHT
2) Hyperkalemia may be exacerbated
by all of the following drugs except:
A. ACE inhibitors
B. Heparin
C. Amphotericin B
D. Trimethoprim
E. Succinylcholine
COPYRIGHT
3) A 35 year old woman is noted by her family to
develop confusion shortly after a birthday
party. Less severe similar episodes have
occurred in the past when she told friends that
she felt temporarily “drunk”.
Past Hx is positive for depression, morbid
obesity and some form of abdominal surgery
for weight loss.
COPYRIGHT
You should suspect that her illness may be
caused by:
A. Salicylate ingestion
B. Acetaminophen ingestion
C. Isopropyl alcohol ingestion
D. Carbohydrate ingestion
E. Toluene ingestion (glue sniffing toxicity)
COPYRIGHT
Laboratory studies reveal the following:
Urinalysis: SG 1.002, pH 6.5, trace glucose, trace protein.
The 24 hour urine output is 6 liters.
Sodium (mEq/L) 146
Potassium (mEq/L) 3.5
Chloride (mEq/L) 112
Bicarbonate (mEq/L) 18
BUN (mg/dL) 10 (3.6 mmol/L)
Creatinine (mg/dL) 0.6 (53 µmol/L)
Calcium (mg/dL) 9.0 (2.3 mmol/L)
Glucose (mg/dL) 145 (8.0 mmol/L)
COPYRIGHT
This patient most probably:
A. has renal tubular acidosis
B. has gestational diabetes mellitus
C. has primary polydipsia
D. will respond to DDAVP for diabetes insipidus
E. should not be given DDAVPCOPYRIGHT
Kidney Stones
COPYRIGHT
5) An otherwise healthy 44-year-old man has recurrent calcium oxalate stones. He is on no medications and has no history of gastrointestinal or urinary tract disease.
Serum electrolytes are normal. Serum calcium and phosphate are repeatedly normal.
Urinalysis is normal with pH of 5.5.
COPYRIGHT
Urinary evaluation (24 hr) reveals:
Calcium 350 mg/day (8.73 mmol)
Oxalate 47 mg/day ( 520 µmol)
Citrate 200 mg/day (1041 µmol)
Urate 860 mg/day (5116 µmol)
Sodium 237 mEq/day
Volume 1,900 ml/day
COPYRIGHT
All of the following therapies could beuseful except:
A. Hydrochlorothiazide
B. Potassium citrate
C. Low sodium diet
D. Low calcium diet
E. Allopurinol COPYRIGHT
6) The previous patient has developed colicky
flank pain and is noted to have a 5 mm stone
in the distal left ureter.
At this time, you advise:
A. Tamsulosin
B. Nifedipine
C. Shock wave lithotripsy
D. Ureteroscopy with stent placement
E. More sex
COPYRIGHT
Renal Disorders
COPYRIGHT
7) A 68 year old woman has noted leg edema
and fatigue. Laboratory studies reveal:
Hgb 9.9 Na 138
BUN 37 K 4.2
Creatinine 1.7 Cl 116
Glucose 96 CO2 17
Calcium 10.1 pH 7.34
Phosphate 1.8 Albumin 2.6
Urinalysis: pH 7.0, 1+ protein, 1+ glucose,
5-15 RBC/hpf, 5-10 WBC/hpf, rare waxy cast
Urine protein/ urine creatinine: 2.7
COPYRIGHT
The most likely diagnosis is:
A. Nephrocalcinosis due to RTA
B. Sjogren’s syndrome with nephropathy
C. Membranous nephropathy associated
with a carcinoma
D. HIV nephropathy
E. Light chain deposition nephropathyCOPYRIGHT
8) A 69 year old man complains of 2 weeks
of cough. Exam is normal as are blood
tests except the creatinine is 1.7 mg/dL
(150 µmol/L). He is treated with 5 days of
levofloxacin.
He returns 2 weeks later (bad followup!!),
now with hemoptysis and a petechial rash
on the lower extremities.
COPYRIGHT
Physical examination shows an ill-appearing
man with blood pressure of 150/98 mmHg.
The lungs reveal bilateral crackles. The rest
of the physical exam is unremarkable except
for raised, non-blanching papules over the
lower extremities. COPYRIGHT
Urinalysis reveals 3+ protein, 3+ hemoglobin
with numerous RBC’s, 5-10 WBC’s, and RBC
and WBC casts.
Serum creatinine is 6.4 mg/dL (566 µmol/L).
Complement levels are normal.
Chest X-ray reveals bilateral pulmonary
infiltrates.
COPYRIGHT
The procedure most likely to yield a useful
diagnosis is:
A. Renal biopsy
B. Bronchoscopy
C. Thoracoscopic lung biopsy
D. Renal arteriogram
E. Serum tests for anti-glomerular basement
antibody (anti-GBM) and anti-neutrophil
cytoplasmic antibodies (ANCA)
COPYRIGHT
9) The most likely diagnosis in the foregoing
patient is:
A. Cryoglobulinemic vasculitis
B. Goodpasture's syndrome
C. Systemic vasculitis associated with an
anti-neutrophil cytoplasmic antibody
D. Henoch-Schonlein purpura
E. Systemic lupus erythematosus
COPYRIGHT
10) A previously healthy 26-year-old man
becomes ill with fever, malaise, back pain,
and sore throat. One day later he notices
gross hematuria.
Urinalysis shows 2+ protein, 3+ blood,
30-40 RBC/hpf with acanthocytes.
The serum creatinine is 0.9.
COPYRIGHT
The most likely cause of the urine findings is:
A. Acute post-streptococcal glomerulonephritis
B. Nephrolithiasis
C. IgA nephropathy
D. Lupus nephritis
E. Granulomatosis with polyangiitis (formerly
Wegener’s granulomatosis)
COPYRIGHT
11) A 48 yo woman returns from 2
months in Brazil with muscle twitching,
cramps, weakness and polyuria.
PMHx: Hypertension on HCTZ;
GERD on omeprazole.
COPYRIGHT
She had received numerous mosquito bites and
testing for zika virus is positive.
Evaluation is also notable for hypokalemia,
hypocalcemia, and widening of her QRS on
ECG.
COPYRIGHT
At this time, you suspect that her new
symptoms have been caused by:
A. Hypokalemia
B. Hypoparathyroidism
C. Hypomagnesemia
D. Guillain Barre syndrome
E. Anxiety about zika virus & pregnancy
COPYRIGHT
12) A 45 year old man who is HIV positive has
had headache, weakness, generalized
aching, nausea and vomiting for one week.
He has a history of hypertension for 3 years
and has been on hydrochlorothiazide for 3
months. He drinks 3-5 alcoholic beverages
a day and admits to past use of intravenous
cocaine and heroin.
COPYRIGHT
On exam, he appears lethargic with a BP of
170/115 mmHg, P of 100/min and T 980 (36.70).
Fundi show arteriolar narrowing. There is mild
jugular venous distension and basilar crackles.
There is 3+ pitting edema of the legs and
generalized tenderness.
Neurologic exam shows weakness, more marked
proximally than distally.
COPYRIGHT
Laboratory tests:
BUN 60 mg/dL (21.4 mmol/L)
Creatinine 9 mg/dL (796 µmol/L)
Sodium 136 mEq/L
Potassium 6.8 mEq/L
Chloride 100 mEq/L
Bicarbonate 14 mEq/L
Calcium 6.4 mg/dL (1.6 mmol/L)
Phosphorus 12.5 mg/dL (4.0 mmol/L)
Uric acid 21 mg/dL (1249 µmol/L)
Bilirubin 0.6 mg/dL (10 µmol/L)
Hematocrit 35 %
WBC 14,000/cu mm
Platelets 125,000/cu mm
COPYRIGHT
Peripheral blood smear shows normal
differential and morphology
Urinalysis: 1+ protein, 4+ heme by dipstick.
Sediment: 3-5 RBC/hpf, 1-3 WBC/hpf;
several coarse granular casts/lpf.
Renal ultrasound: normal kidney size
without evidence for obstruction
COPYRIGHT
Evaluation of the renal failure would most
likely reveal:
A. hypertensive nephrosclerosis
B. allergic interstitial nephritis secondary to
thiazide therapy
C. systemic vasculitis with a crescentic
glomerulonephritis
D. acute tubular necrosis
E. focal glomerular sclerosis with
collapsing glomerulopathy
F. urate nephropathy
COPYRIGHT
13) A 26 year old woman is admitted to the
hospital following a one to two week diarrheal
illness. She has been febrile and confused at
home.
On exam, she is delirious with a BP 140/90,
P 110/min, T 103ºF (39.4ºC). There is no clear
source of fever. Stool is green and bloody.
COPYRIGHT
Laboratory studies show a hematocrit of 24%,
WBC of 8,200 without band forms and
platelet count of 62,000. The peripheral blood
smear reveals numerous schistocytes.
The BUN is 78 mg/dL (27.8 mmol/L).
The creatinine is 4.2 mg/dL (371 µmol/L).
The urinalysis reveals 2+ protein, 10-20
RBC/hpf and granular casts.
COPYRIGHT
You would start :
A. Treatment only after special tests return
B. Antibiotics targeted against Gram-negative
organisms
C. Supportive care
D. Corticosteroids and cyclophosphamide
E. Plasma exchange therapy + FFPCOPYRIGHT
14) A 52-year-old woman with known
polycystic kidney disease develops low
grade fever and mild left flank pain.
Urinalysis reveals numerous white blood
cells, red blood cells and bacteria. The
urine gram stain reveals gram-negative
rods.
COPYRIGHT
The best treatment option for this patient is:
A. Intravenous gentamicin for presumed Gram-negative
bacterial urinary tract infection
B. Begin both gentamicin and cephalothin therapy to
achieve synergy of two antibiotics in the urine and
fluid of an infected cyst
C. Begin either oral ciprofloxacin or sulfa-trimethoprim
D. Obtain an US or CT to look for an infected cyst
E. Both C and D
COPYRIGHT
Extra Credit Question
COPYRIGHT
15) A 25 yo man develops fever, myalgias,
headache and cough 10 days after his return from
a kayaking vacation in Hawaii.
Physical exam
shows T 100.5° F
(38°C), no distress,
a tender enlarged
liver and ‘classic’
head exam as
shown.
COPYRIGHT
Laboratory studies reveal the following:
Sodium (mEq/L) 132
Potassium (mEq/L) 3.3
Chloride (mEq/L) 101
Bicarbonate (mEq/L) 24
BUN (mg/dL) 54 (19 mmol/L)
Creatinine (mg/dL) 2.6 (230 µmol/L)
ALT (U/L) 340 (5.7 µkat/L)
Total bilirubin (mg/dL) 12 (205 µmol/L)
Hgb 11.4/µL, WBC 9,800/µL (82% polys), Platelets 90,000/µL
Urinalysis: Nonoliguric, SG 1.008, pH 5.0, 1+ protein,
3-5 RBC/hpf, 15 WBC/hpf, few coarse granular casts
COPYRIGHT
At this time, you would
A. Suspect hepatitis B with renal disease
B. Start high dose corticosteroids
C. Start steroids & immunosuppressive Rx
D. Start antibiotic Rx
E. Supportive Rx alone with IV fluids, etc. COPYRIGHT