Nephrology - PACKRAT Questions

History & Physical/Urology/Renal

A patient with a 15-year history of type 2 diabetic mellitus presents for follow-up. Labs reveal a BUN 100 mg/dl, serum creatinine 9.2 mg/dl, and serum glucose 164 mg/dl. Which of the following would you expect to find on physical examination?

Answers

A. Pruritus

B. Hypotension

C. Macroglossia

D. Suprapubic tenderness

Explanations

(c) A. Hypertension, pruritus and xerosis are common findings in the uremic patient.

(u) B. See A for explanation.

(u) C. See A for explanation.

(u) D. Suprapubic tenderness is associated with urinary tract infection or acute obstructive uropathy.

Diagnostic Studies/Urology/Renal

A 38 year-old female presents with right flank pain for several days, shaking chills, fever to 102°F, and general malaise. The flank pain has been intermittently severe, and she has a history of kidney stones. Urinalysis reveals 3+ red blood cells, 3+ leukocyte esterase, trace protein and negative glucose. Which of the following findings would most likely be seen on a renal ultrasound?

Answers

A. Small echogenic kidneys

B. Cysts

C. Hydronephrosis

D. Capsular hemorrhage

Explanations

(u) A. Small echogenic kidneys bilaterally, less than 10cm, support a diagnosis of chronic renal failure.

(u) B. Cysts and capsular hemorrhage are not causes of obstructive pyelonephritis.

(c) C. Hydronephrosis, dilation of the collecting ducts, may be present due to a stone or other source of obstruction.

(u) D. See B for explanation.

Diagnostic Studies/Urology/Renal

A 65 year-old patient presents with hypertension and peripheral edema. Urinalysis reveals pale urine, with a specific gravity of 1.002, 2+ protein, trace glucose, and is negative for red blood cells and leukocytes. Serum electrolytes include BUN of 58 mg/dl and creatinine of 4.5 mg/dl. These are unchanged from previous results obtained 3 months and 6 months ago. Of the following, what other laboratory abnormalities would you expect?

Answers

A. Hypercalcemia

B. Metabolic alkalosis

C. Hypophosphatemia

D. Anemia

Explanations

(u) A. Patients with chronic renal failure typically present with hypocalcemia, hyperphosphatemia, and metabolic acidosis.

(u) B. See A for explanation.

(u) C. See A for explanation.

(c) D. Anemia of chronic disease is associated with chronic renal failure.

Diagnosis/Urology/Renal

A 65 year-old male with a 60 pack-year smoking history presents with painless hematuria for two days. He also complains of frequency and dysuria. He denies a history of recent upper respiratory tract infection. Which of the following is the most likely diagnosis?

Answers

A. Bladder cancer

B. Wegener's granulomatosis

C. IgA nephropathy

D. Benign prostatic hypertrophy

Explanations

(c) A. Bladder cancer is associated with smoking and presents with painless hematuria.

(u) B. Wegener's granulomatosis disease involves the kidneys and the lungs. Renal signs include hematuria, red blood cells casts, and proteinuria.

(u) C. IgA nephropathy typically presents after an upper respiratory tract infection and presents with hematuria and proteinuria.

(u) D. BPH presents with voiding symptoms such as hesitancy, straining, weak stream and postvoid dribbling.

Health Maintenance/Urology/Renal

Patients with recurrent urinary stone disease should be educated to maintain a diet restricted in

Answers

A. sodium and protein.

B. carbohydrates and fat.

C. bran.

D. fluids.

Explanations

(c) A. Increased sodium intake will increase sodium and calcium excretion and increase monosodium urate saturation. Protein also increases calcium, oxalate and uric acid excretion. All these factors can lead to stone formation.

(u) B. Carbohydrates and fat do not have any impact on urinary stone disease.

(u) C. Bran significantly lowers urinary calcium, reducing risk for stone recurrence.

(u) D. Increased fluids is important in reducing stone recurrence.

Clinical Intervention/Urology/Renal

A 32 year-old female patient presents with renal colic and hematuria. The patient has a long-standing history of unresponsive treatment for urinary tract infections with documented Proteus species. Urinalysis reveals crystals resembling coffin lids. KUB reveals a staghorn calculus in the right kidney. Which of the following is the best clinical intervention?

Answers

A. High fluid intake with a low salt diet B. A low purine diet

C. Laser lithotripsy

D. Percutaneous nephrolithotomy

Explanations

(u) A. High fluid intake (>3L/day) and a low salt diet is helpful in patients with cystine stones.

(u) B. Low purine diets are instituted in patients who form uric acid stones with hyperuricosuria.

(u) C. Laser lithotripsy is used for removal of ureteral stones via a urethroscope.

(c) D. Percutaneous nephrolithotomy is currently the primary surgical intervention of choice for struvite stones.

Diagnosis/Urology/Renal

A patient presents with edema, which is most noticeable in the hands and face. Laboratory findings include proteinuria, hypoalbuminemia, and hyperlipidemia. The most likely diagnosis is

A. congestive heart failure.

B. end-stage liver disease.

C. nephrotic syndrome.

D. malnutrition.

Explanations

(u) A. Dependent edema is the most typical finding with CHF. Laboratory findings do not generally include proteinuria or hypoalbuminemia.

(u) B. Symptoms of end-stage liver disease usually include increased abdominal girth indicating ascites. Hypoalbuminemia can occur as a result of malnutrition or concurrently with nephrotic syndrome.

(c) C. Proteinuria, hyperlipidemia, and hypoalbuminemia are consistent with nephrotic syndrome.

(u) D. Malnutrition is marked by physical wasting, not edema. Hypoalbuminemia may be seen, but hyperlipidemia is

not typical.

History & Physical/Urology/Renal

Which of the following is most frequently associated with bladder cancer?

A. Hematuria

B. Dysuria

C. Urgency

D. Frequency

Explanations

(c) A. Significant persistent hematuria >3 RBC/HPF on three urinalyses, a single urinalysis with >100 RBC, or gross hematuria, identifies significant renal or urologic lesions. Bladder cancer usually presents with painless hematuria.

(u) B. Dysuria, urgency, and frequency are associated with irritative voiding symptoms associated with cystitis.

(u) C. See B for explanation.

(u) D. See B for explanation.

Diagnostic Studies/Urology/Renal

Which of the following diagnostic findings in the urinary sediment is specific for a diagnosis of chronic renal failure?

A. Hematuria

B. Proteinuria

C. Broad waxy casts

D. Hyaline casts

Explanations

(u) A. Hematuria and proteinuria are frequent, but nonspecific, findings in chronic renal failure.

(u) B. See A for explanation.

(c) C. Broad waxy casts in urinary sediment are a specific finding in chronic renal failure.

(u) D. Hyaline casts may be found in normal urine or in states of dehydration.

Diagnosis/Urology/Renal

Lab results for a post-operative oliguric patient reveals an increased BUN to creatinine ratio. The patient has a low fractional excretion of sodium (less than 1%). Which of the following is the most likely diagnosis?

A. prerenal azotemia

B. acute tubular necrosis

C. acute glomerulonephritis

D. obstructive uropathy

Explanations

(c) A. Patients who have prerenal azotemia with otherwise normal kidneys will have severe sodium retention in order to help to save fluid. The amount of sodium in the urine is therefore very low.

(u) B. Acute tubular necrosis may occur in the post-operative setting but these kidneys are damaged and unable to save sodium.

(u) C. Acute glomerulonephritis is a complication of a streptococcal infection wherein the immune complexes damage the glomeruli and lead to hematuria, red blood cell casts, and proteinuria.

(u) D. Although patients who undergo abdominal surgery are at risk for damage to the genital urinary system, these patients will not have sodium retention because it is a post renal, not a prerenal injury.

Diagnosis/Urology/Renal

A 52 year-old patient presents with fatigue, complaints of paleness, anorexia, nausea, and weight loss. The patient also complains of numbness in his hands and feet and a recent occurrence of foot drop. He has a past history of diabetes and hypertension. Based on his clinical presentation, which of the following disorders is most likely to be responsible for this clinical picture?

A. chronic renal failure

B. middle cerebral artery occlusion

C. Guillain-Barre syndrome

D. Raynaud's phenomena

Explanations

(c) A. Patients with chronic renal failure will have accelerated atherosclerosis, hypertension, anemia due to lack of erythropoietin production, a tendency toward GI symptoms of anorexia, nausea, and weight loss, and neurological symptoms of peripheral neuropathy that occurs in a stocking and glove distribution along with peripheral motor impairment such as foot drop and restless legs syndrome. Diabetes and hypertension are risk factors for the development of chronic renal disease.

(u) B. Middle cerebral artery occlusion would consist of contralateral neurologic impairment rather than bilateral stocking glove neurological impairment

(u) C. Guillain-Barre is a condition manifested by an ascending paralysis.

(u) D. Raynaud's phenomena is a clinical condition in which patients exhibit pain and pallor of their distal extremities when they are exposed to cold. Upon rewarming, the patient will experience redness as part of the color changing sequence. Raynaud's typically does not cause the other symptoms described in the case scenario.

History & Physical/Urology/Renal

A male patient presents with hematuria. Upon further questioning the patient states that the hematuria occurs at the end of his urinary stream. Which of the following is the most likely source of blood?

A. renal pelvis

B. bladder neck

C. anterior urethra

D. ureter

Explanations

(u) A. Total hematuria, blood throughout the urinary stream, suggests a bladder or upper urinary tract source.

(c) B. Terminal hematuria, blood at the end of the urinary stream, suggests a bladder neck or prostatic urethral source.

(u) C. Presence of blood at the beginning of the urinary stream suggests an anterior (penile) urethral source.

(u) D. Hematuria from the kidneys or ureter may be present microscopically or throughout the stream.

Clinical Therapeutics/Urology/Renal

Which of the following treatments of constipation should be used with extreme caution in patients who have chronic renal insufficiency?

A. milk of magnesium

B. psyllium (Metamucil)

C. docusate sodium (Colace)

D. lactulose (Chronulac)

Explanations

(c) A. Patients with chronic renal insufficiency have difficulty excreting magnesium and hypermagnesemia almost always occurs in a patient with chronic renal insufficiency.

(u) B. Psyllium is a fiber rich product that helps to bulk up the stool. It can be safely used in the constipated renal patient.

(u) C. Docusate sodium is a stool softener that does not accumulate in the patient with renal insufficiency so it can be safely used.

(u) D. Lactulose is an agent that is an unabsorbable sugar that can be safely used to treat constipation in the patient with chronic renal insufficiency.

Health Maintenance/Urology/Renal

The most effective preventive strategy to prevent recurrence of renal lithiasis is which of the following?

A. increase in hydration

B. early treatment of urinary tract infection

C. limitation of calcium intake

D. use of probenecid

Explanations

(c) A. Keeping the urine dilute is the most effective strategy to prevent crystal accumulation in the urine and the development of urinary stones.

(u) B. Treating UTI only affects the formation of calcium pyrophosphate or struvite stones.

(u) C. Limitation of calcium in the diet reduces the ability of calcium to bind oxalate leading to the production of calcium oxalate stones.

(u) D. Probenecid is a uricosuric agent that promoted uric acid secretion in the urine that may promote more uric acid stones.

Diagnostic Studies/Urology/Renal

A urinalysis performed during a routine physical examination on a 43 year-old male reveals 1-2 hyaline casts/HPF. The remainder of the UA is normal. Based upon these results, the physician assistant should

A. collect a urine for culture and sensitivity.

B. do nothing, since these casts are considered normal.

C. refer the patient to a nephrologist.

D. schedule the patient for a CT scan.

Explanations

(u) A. See B for explanation.

(c) B. Hyaline casts are not indicative of renal disease. They can be found following strenuous exercise and with concentrated urine or during a febrile illness.

(u) C. See B for explanation.

(u) D. See B for explanation.

Scientific Concepts/Urology/Renal

Which of the following is the most common composition of kidney stones?

A. calcium oxalate

B. uric acid

C. struvite

D. calcium phosphate

Explanations

(c) A. Approximately three fourths of all kidney stones are comprised of calcium oxalate.

(u) B. See A for explanation.

(u) C. See A for explanation.

(u) D. See A for explanation.

Clinical Therapeutics/Urology/Renal

When treating a patient with BPH who complains of increased frequency, urgency, decreased force of stream and hesitancy with an alpha-adrenergic blocking agent, the patient should be warned of what possible side effect?

A. hypertensive crisis

B. postural hypotension

C. development of prostate cancer

D. development of testicular cancer

Explanations

(u) A. Alpha-adrenergic agents do not cause hypertension.

(c) B. This class of medications can cause postural hypotension as a result of the decrease in peripheral vascular resistance and lower arterial blood pressure by causing relaxation of the arterial and venous smooth muscle.

(u) C. Alpha-adrenergic agents have no effect on testosterone levels, which have been suggested as a possible link to the development of prostate cancer.

(u) D. Alpha-adrenergic agents have no correlation to the development of testicular cancer.

Clinical Intervention/Urology/Renal

Which of the following is the treatment of choice for a nursing home patient who has asymptomatic bacteriuria with no history of diabetes or structural abnormalities of the genitourinary tract?

A. ciprofloxacin (Cipro)

B. sulfamethoxazole-trimethoprim (Bactrim)

C. cephalexin (Keflex)

D. no treatment is needed

Explanations

(u) A. See D for explanation.

(u) B. See D for explanation.

(u) C. See D for explanation.

(c) D. Asymptomatic bacteriuria is commonly seen in the geriatric population and no treatment is needed in most patients

History & Physical/Urology/Renal

Which of the following signs and symptoms is typically noted in patients with acute cystitis?

A. Fever and chills

B. CVA tenderness

C. Flank pain

D. Frequency and dysuria

Explanations

(u) A. Signs of systemic toxicity, such as fever and chills, are absent in acute cystitis.

(u) B. CVA tenderness and flank pain are associated with acute pyelonephritis.

(u) C. See B for explanation.

(c) D. Irritative voiding symptoms, such as frequency and dysuria, are common in acute cystitis.

History & Physical/Urology/Renal

Which of the following is most frequently associated with renal cell carcinoma?

A. Hematuria

B. Inguinal pain

C. Hypocalcemia

D. Fever

Explanations

(c) A. Gross or microscopic hematuria, flank pain, or mass is common in renal cell carcinoma.

(u) B. See A for explanation.

(u) C. Hypercalcemia, not hypocalcemia, may be noted in patients with renal cell carcinoma.

(u) D. Fever is uncommon in renal cell carcinoma and typically only noted with advanced disease.

Diagnosis/Urology/Renal

A 15 year-old male patient presents with oliguria, hematuria, proteinuria, and fatigue following streptococcal pharyngitis 2 weeks ago. Which of the following is the most likely diagnosis?

A. Acute pyelonephritis

B. Acute glomerulonephritis

C. Systemic lupus erythematosus

D. Initial onset of type 1 diabetes mellitus

Explanations

(u) A. Acute pyelonephritis presents with fever, flank pain, urgency, and pyuria.

(c) B. Acute glomerulonephritis is a complication that can follow a streptococcal infection after 1 to 3 weeks.

(u) C. Systemic lupus erythematosus is not a complication of streptococcal infections, but it can cause rapid progressive glomerulonephritis.

(u) D. Diabetes mellitus presents with polyuria, not oliguria or hematuria.

Diagnosis/Urology/Renal

A 25 year-old female presents with right lower quadrant pain, right flank pain, nausea, and vomiting. Her temperature is 39.6 degrees C. There is right CVA tenderness and RLQ tenderness. Pelvic exam is unremarkable. Urinalysis reveals pH 7.0, trace protein, negative glucose, negative ketones, positive blood, and positive nitrates. Specific gravity is 1.022. Microscopic shows 102 RBCs/HPF, 50-75 WBCs/HPF, rare epithelial cells, and WBC casts. The most likely diagnosis is

A. acute salpingitis.

B. nephrolithiasis.

C. acute pyelonephritis.

D. appendicitis.

Explanations

(u) A. Acute salpingitis would be suggested if pelvic exam abnormalities were present.

(u) B. Nephrolithiasis does not usually present with fever or casts. Urinalysis will have RBCs present.

(c) C. Acute pyelonephritis presents with flank pain, fever, and generalized muscle tenderness. Urinalysis shows pyuria with leukocyte casts.

(u) D. This scenario is consistent with acute pyelonephritis, not acute appendicitis.

Clinical Intervention/Urology/Renal

A 40 year-old patient with a history of recurrent kidney stones presents with acute onset of right flank pain and hematuria. The patient is afebrile and pain is poorly controlled on oral medications. On CT scan a 1 cm stone is noted in the renal pelvis. Which of the following is the most appropriate intervention for this patient?

A. Antibiotics

B. Shock wave lithotripsy

C. Ureterolithotomy

D. Fluid hydration

Explanations

(u) A. There is no indication of infection and antibiotics are not warranted at this time.

(c) B. Extracorporeal shock wave lithotripsy is indicated in patients with stones greater than 6 mm in size or intractable pain.

(u) C. Ureterolithotomy is an open surgical procedure and therefore very invasive. In this situation an ESWL would be as effective and safer.

(u) D. While fluid hydration is indicated, a stone greater than 6 mm will typically not spontaneously pass and surgical therapy is indicated.

Clinical Therapeutics/Urology/Renal

Which of the following agents can be used as a urinary analgesic?

A. Phenazopyridine (Pyridium)

B. Oxybutynin (Ditropan)

C. Finasteride (Proscar)

D. Imipramine (Tofranil)

Explanations

(c) A. Phenazopyridine is a urinary tract analgesic used in the treatment of urinary tract discomfort.

(u) B. Oxybutynin is an antispasmodic and anticholinergic used in the treatment of overactive bladder.

(u) C. Finasteride is an alpha-blocker used in the treatment of benign prostatic hypertrophy.

(u) D. Imipramine is an anticholinergic used to treat childhood enuresis.

Health Maintenance/Urology/Renal

In order to prevent the progression of diabetic nephropathy which of the following medications should be instituted?

A. Lisinopril (Prinipril)

B. Propanolol (Inderal)

C. Verapamil (Calan)

D. Hydrochlorothiazide (Diuril)

Explanations

(c) A. All patients should be started on an ACE inhibitor to prevent the progression of proteinuria. ACE inhibitors appear to improve glomerular hemodynamics by decreasing glomerular pressure.

(u) B. Beta blockers are not indicated for the treatment of microalbuminuria.

(u) C. Calcium channel blockers are not indicated for the treatment of microalubuminuria.

(u) D. Thiazide diuretics are not indicated for the treatment of microalbuminuria.

Diagnostic Studies/Urology/Renal

A 48 year-old female presents to the clinic complaining of hematuria. The patient states that she was found to have hematuria during an insurance physical examination. The patient denies dysuria or frequency. She also denies pain in the abdomen, flank or meatus. She denies any history of previous nephrolithiasis. Urinalysis reveals the urine to be yellow and slightly hazy with a positive dipstick for hemoglobin. Microscopic reveals 5-7 RBCs/HPF without WBCs, bacteria, casts, or crystals. What is the next diagnostic study this patient should undergo?

A. CT urography

B. Intravenous pyelogram

C. Abdominal ultrasound

D. Cystoscopy

Explanations

(c) A. CT urography with and without contrast should be done to evaluate the upper and lower urinary tract for neoplasms, and benign conditions such as urolithiasis. This has replaced IVP for imaging of the upper tracts. Abdominal ultrasound will not help in this scenario and the role of renal ultrasound in evaluation of hematuria is unclear. Cystoscopy will help to assess the bladder and urethra but will not help with evaluation of the upper urinary tract.

(u) B. See A for explanation.

(u) C. See A for explanation.

(u) D. See A for explanation.

Scientific Concepts/Urology/Renal

Which of the following is the portion of the nephron responsible for the absorption of 90% of the ultrafiltrate?

A. Proximal convoluted tubule

B. Loop of Henle

C. Distal convoluted tubule

D. Collecting duct

Explanations

(c) A. The majority of the ultrafiltrate 90% is reabsorbed in the proximal convoluted tubule.

(u) B. The loop of Henle is responsible for the concentration of solutes within the nephron.

(u) C. The distal convoluted tubule is responsible for some water and sodium reabsorption.

(u) D. The collecting duct is responsible for the final concentration of the urine.

Diagnosis/Urology/Renal

A 9 year-old boy who has had cold-like symptoms for the past few days is brought to the clinic by his mother who states that her son had gross hematuria this morning. Prior to the cold-like symptoms the boy has been in excellent health. He is up-to-date on all of his immunizations. The patient does not have any edema, hypertension or purpura. Urinalysis reveals the urine to be cola-colored with a 2+ positive protein and 2+ hemoglobin. Microscopic analysis reveals 50-100 RBCs/HPF, no WBCs, bacteria, casts or crystals. What is the most likely diagnosis?

A. Post streptococcal glomerulonephritis (PSGN)

B. IgA nephropathy

C. Minimal change disease (MCD)

D. Membranous nephropathy

Explanations

(u) A. PSGN usually presents 2-3 weeks after a streptococcal infection (pharyngeal or skin) and usually presents with nephritic symptoms (edema, hypertension, cola-colored urine). This is due to trapping of the streptococcal antigen within the glomerulus

(c) B. IgA nephropathy presents after an upper respiratory illness with deposition of IgA within the mesangium of the glomerulus.

(u) C. MCD is the most common nephrotic presentation (edema, hypoproteinemia, hyperlipidemia, >3.5 gms. of proteinuria in 24 hours) in children following an upper respiratory illness. This patient is not exhibiting any of these signs at this time.

(u) D. Membranous nephropathy is the most common cause of adult nephrotic syndrome.

Clinical Therapeutics/Urology/Renal

Which of the following medications is most likely to cause acute tubular necrosis?

A. Trimethoprim-sulfamethoxazole (Bactrim)

B. Acetaminophen

C. Cephalothin (Kefzol)

D. Gentamicin

Explanations

D. think cake man C

In hospitalized patients up to 25% of patients receiving aminoglycosides sustain some degree of acute tubular necrosis. Gentamicin is one of the most toxic aminoglycosides, streptomycin is the least nephrotoxic of the aminoglycosides.

Diagnosis/Urology/Renal

An elderly appearing adult male patient is transported to the emergency room with unconsciousness for an underdetermined amount of time. There is no family and the only history is provided by the paramedics. The patient arouses to verbal and painful stimuli. VS: T-97.0 degrees F rectally, P-52 bpm, R-10, BP-95/60 mmHg. Physical examination is unremarkable except for ecchymosis across his extremities. A Foley catheter is inserted draining a small amount of dark brown urine. Urine dipstick reveals 4+ positive hemoglobin and protein. Microscopic urinalysis reveals no RBCs but many renal tubular epithelial cells and renal tubular casts. Drug screen is negative, blood alcohol is 2.5 mg/dL, and creatinine is 4.9 mg/dL. What is the most likely diagnosis?

A. Rhabdomyolysis causing acute renal failure

B. Obstructive uropathy causing acute renal failure

C. Ethanol ingestion causing acute renal failure

D. Methanol ingestion causing acute renal failure

Explanations

(c) A. Since the patient was found unconscious for an undetermined amount of time and the blood alcohol is elevated the patient has been in a state of prolonged immobilization resulting in muscle ischemia resulting in myoglobinuria. This is responsible for turning the dipstick positive without the RBCs seen on the urinary

microscopy. The myoglobin causes an acute tubular necrosis resulting in the sloughing of the renal tubular epithelium. Obstructive uropathy does not cause acute tubular necrosis and occurs over time. Methanol ingestion causes visual symptoms, ethylene glycol causes renal failure.

(u) B. See A for explanation.

(u) C. See A for explanation.

(u) D. See A for explanation.

Clinical Intervention/Urology/Renal

A patient has been followed for 3 years with a continual decline in glomerular filtration rate (GFR). Currently the GFR is 10 ml/min and examination of the patient reveals a pericardial friction rub. Which of the following is the most appropriate intervention at this time?

A. Hemodialysis

B. Continue to observe

C. Administration of high dose steroids

D. Bilateral nephrectomy

Explanations

(c) A. The patient has end stage renal disease and with the pericardial friction rub is in need of immediate hemodialysis.

(u) B. The patient already has significant renal compromise, further observation will continue to lead to further complications.

(u) C. High dose steroids have no benefit in end stage renal disease.

(u) D. Surgical removal of the kidneys will not change the progression of the disease.

Diagnosis/Urology/Renal

A 22 year-old woman comes to the office because her urine is cola-colored and she has not urinated since yesterday morning. Her past medical history is significant for pharyngitis two weeks ago. Her mother and grandmother have type 2 diabetes. Her blood pressure is 146/92mmHG. On physical examination, she has edema of her face and hands. Which of the following is the most likely diagnosis?

A. Glomerulonephritis

B. Acute tubular necrosis

C. Nephrolithiasis

D. Diabetic nephropathy

Explanations

(c) A. Glomerulonephritis presents with hematuria, cola-colored urine, oliguria, and edema of the face and eyes in the morning. Urinalysis reveals red blood cells, mild proteinuria and red blood cell casts. Glomerulonephritis can occur 1-3 weeks after a strep infection.

(u) B. Acute tubular necrosis is caused by acute kidney injury, such as a nephrotoxin, and is associated with uremic symptoms which include nausea, vomiting, malaise, and altered mental status. Granular casts are non- specific and may be seen in acute tubular necrosis.

(u) C. Nephrolithiasis usually presents as a sudden onset of colicky flank pain with associated nausea and vomiting. Urinalysis often reveals gross or microscopic hematuria.

(u) D. Diabetic nephropathy is the most common cause of end stage renal disease in the United States. Urine examination reveals albuminuria.

Scientific Concepts/Urology/Renal

Which of the following is a cause of acute kidney failure due to prerenal azotemia?

A. Excessive diuresis

B. Urinary tract obstruction

C. Radiologic contract media

D. Aminoglycosides

Explanations

(c) A. Prerenal azotemia is due to renal hypoperfusion which can occur with intravascular volume depletion such as excessive diuresis, hemorrhage, and gastrointestinal losses.

(u) B. Postrenal azotemia is due to obstruction of urinary flow from both of the kidneys.

(u) C. Radiologic contrast media can be directly nephrotoxic causing acute tubular necrosis, which is an intrinsic renal disease.

(u) D. Exogenous nephrotoxins, such as aminoglycosides, cause acute tubular necrosis, which is an intrinsic renal disease.

Health Maintenance/Urology/Renal

A 48 year-old male with a recent episode of nephrolithiasis comes to the office to discuss prevention of further urinary stone disease. Which of the following dietary recommendations can reduce recurrence of nephrolithiasis?

A. Increase fluid intake

B. Decrease dietary fiber

C. Increase salt intake

D. Decrease calcium intake

A !

Diagnostic Studies/Urology/Renal

A 28 year-old female comes to the office with fever, flank pain, and dysuria for the past two days. Which of the following urinalysis results are suggestive of acute pyelonephritis?

A. Hyaline casts

B. Red cell casts

C. White cell casts

D. Granular casts

Explanations

(u) A. Hyaline casts may be found in concentrated urine and are not indicative of renal disease.

(u) B. Red cell casts are indicative of glomerulonephritis.

(c) C. White cell casts are indicative of renal infection or inflammation as seen in pyelonephritis or interstitial nephritis.

(u) D. Granular casts are non-specific and may be seen in acute tubular necrosis

Diagnostic Studies/Urology/Renal

A 54 year-old woman with history of lupus comes to the office with increasing significant peripheral edema over the past four days. Laboratory findings include marked proteinuria, hypoalbuminemia and hyperlipidemia. Which of the following diagnostic studies is the best for determining the cause of the proteinuria?

A. Renal ultrasound

B. Renal biopsy

C. Cystoscopy

D. Computed tomography scan

Explanations

(u) A. Renal ultrasound may identify hydronephrosis from a stone or other source of obstruction.

(c) B. Renal biopsy is performed in adults with new onset of nephrotic syndrome to determine the cause of the proteinuria and to guide management decisions.

(u) C. Cystoscopy can be used in the evaluation of hematuria to assess for bladder or urethral neoplasm, benign prostatic hyperplasia, and radiation or chemical cystitis.

(u) D. CT scanning may identify neoplasms of the kidney or ureter as well as benign conditions such as urolithiasis.

A 73 year-old male with chronic renal failure due to longstanding hypertension and diabetes is being discharged from the hospital today. Which dietary recommendation should be made to prevent further complications and progression of his renal disease?

A. Increase salt intake

B. Restrict dietary protein

C. Add a daily potassium supplement

D. Decrease gluten consumption

Explanations

(u) A. Increased salt intake can lead to volume overload in patients with chronic renal disease.

(c) B. Restricting protein in the diet may slow the progression of chronic kidney disease.

(u) C. Hyperkalemia can develop in patients with chronic renal failure who are taking supplements or have a high potassium diet.

(u) D. Decreasing gluten consumption has no effect on renal failure.