Chapter 09: Renal and Metabolic Disease

15. One of the most common causes of Fanconi's syndrome is: A. Cystinosis B. Glycosuria C. Rhabdomyolysis D. Nephrotoxins

ANS: A Fanconi's syndrome is characterized by any condition that presents with generalized loss of proximal tubular function and excretion of amino acids, glucose, water, phosphorus, potassium, and calcium in the urine. Cystinosis is an inherited autosomal recessive disorder that causes renal tubular dysfunction and excretion of amino acid cystine. Glycosuria is the presence of glucose in the urine, a common finding in diabetes mellitus. Rhabdomyolysis results in excretion of myoglobin in urine as a result of skeletal muscle injury. Cognitive Level: 1 Reference:

3. The pathogenesis of glomerular damage marked by immune-mediated processes involves: A. Antigen-antibody complexes B. Antibodies reacting directly with glomerular tissue antigens C. Nonglomerular antigens that reside in the glomeruli D. B and C

ANS: A Immune-mediated processes are the primary mode of glomerular injury. A second immune mechanism involves antibodies that react directly with glomerular tissue antigens or with nonglomerular antigens. Cognitive Level: 1 Reference:

6. The pathogenesis of all of the following forms of primary glomerulonephritis is antibody mediated except: A. Minimal change disease B. Acute glomerulonephritis C. Rapidly progressive glomerulonephritis D. Membranous glomerulonephritis

ANS: A Minimal change disease is a T-cell immunity dysfunction, whereas the other choices are antibody mediated. Cognitive Level: 1 Reference:

19. The most common pathogen in UTIs is: A. Escherichia coli B. Enterobacter sp. C. Pseudomonas sp. D. Enterococci

ANS: A Approximately 85% of all UTIs are caused by gram negative rods spread from the bowel to the urinary tract system. The most common pathogen is E. coli. Cognitive Level: 1 Reference:

21. The progressive loss of the GFR in chronic renal failure clinically presents when the patient shows which of the following? A. Loss of 80% to 85% of normal renal function B. Decreased renal perfusion C. Atherosclerosis of intrarenal arteries D. Increased frequency of UTIs

ANS: A Because of the great efficiency of the glomeruli, progressive loss of renal function and the decreasing GFR do not become clinically recognizable until 80% to 85% of normal renal function has been lost. Cognitive Level: 1 Reference:

22. Which of the following plays an important role in the formation of renal calculi? A. Isohydruria B. Hypotonicity of urine C. Isosthenuria D. Decreased nucleation

ANS: A Renal calculi formation is enhanced when a patient loses the normal acid-alkaline tide of the body and experiences an unchanging urinary pH, referred to as isohydruria. Other factors that influence the formation of renal calculi include an optimal urinary pH, urinary stasis, supersaturation of chemical salts in the urine, and nucleation or initial crystal formation. Hypotonicity of urine is dilute urine, which helps keep crystals in solution. Isosthenuria refers to a fixed SG of 1.010. Cognitive Level: 1 Reference:

1. Secondary glomerular diseases include which types of disorders? A. Systemic B. Immunologic C. Metabolic D. Hereditary

ANS: A Systemic disorders are technically considered secondary glomerular diseases, because they involve other organs, and the glomeruli become involved as a consequence of the systemic disease progression. Immunologic, metabolic, and hereditary diseases are not considered secondary glomerular diseases. Cognitive Level: 1 Reference:

20. A 23-year-old female presents to the ED with sudden onset of flank and back pain, dysuria, and urgency. She is febrile and has chills, nausea, and headache. She reports no illnesses in the preceding weeks, and she currently is not taking any medications. A urinalysis is ordered, and the results are as follows: Physical Examination Color: Yellow Clarity: Cloudy Chemical Examination Sp. Gr. 1.010 pH 5.5 Blood: Trace Protein: Trace LE: Positive Nitrite: Positive Glucose: Negative Ketones: Negative Bilirubin: Negative Urobilinogen: 1.0 EU Microscopic Examination 50-75 WBCs; clumps Macrophages noted 5-10 RBCs 2-4 Renal epithelial cells 2+ Bacteria Casts: 3-6 WBC/lpf 0-2 Granular Based on the clinical signs and symptoms and the UA results, the most likely diagnosis is: A. Acute pyelonephritis B. Acute glomerulonephritis C. Acute cystitis D. Renal calculi

ANS: A The clinical signs and symptoms, along with the UA results, indicate acute pyelonephritis. The microscopic examination shows increased WBCs, clumps, macrophages, and WBC casts, which all are indicative of this disease. In renal calculi, the microscopic results would reveal RBCs and crystals; acute cystitis would show increased WBCs and bacteria. Acute glomerulonephritis would exhibit RBCs and RBC and hemoglobin casts. Cognitive Level: 3 Reference:

27. A 21-year-old female presents at the university clinic with complaints of increased thirst, urination, and hunger. She says that she eats constantly, yet she has lost about 10 pounds and her weight is down to 100 pounds. She is tired all the time, and her vision is a little blurry. She also reports that her urine smells "sort of fruity." Her blood pressure, temperature, and pulse all are normal at the time of examination. The patient's past clinical history reveals no previous disease conditions. Urinalysis and blood work are ordered. Her blood glucose level is 600 mg/dL, and the UA results are as follows: Physical Examination Chemical Examination Microscopic Examination Color: Pale yellow Clarity: Clear Sp. Gr. 1.035 pH 5.5 Blood: Negative Protein: Negative LE: Negative Nitrite: Negative Glucose: 1000 mg/dL Ketones: Large Bilirubin: Negative Urobilinogen: 1.0 EU 0-2 WBCs Based on the clinical symptoms and laboratory results, the most likely diagnosis is: A. Type 1 diabetes B. Type 2 diabetes C. Diabetes insipidus D. Renal tubular acidosis

ANS: A Type 1 diabetes may be diagnosed at any age, but it usually is diagnosed in children, adolescents, and young adults. The primary risk factor for type 2 diabetes is obesity. This patient weighs 100 pounds, so type 2 diabetes is not indicated. Diabetes insipidus results in a low SG and a negative glucose. Cognitive Level: 3 Reference:

14. A 65-year-old male is admitted to the hospital suffering from azotemia, hyperkalemia, metabolic acidosis, and oliguria. The patient is currently being treated with an aminoglycoside for a urinary tract infection. The physician suspects toxic tubular necrosis and expects to see which of the following listed on the urinalysis report? A. Proximal renal tubular cell B. Bacteria C. Broad casts D. Low specific gravity

ANS: A With toxic tubular necrosis, the UA reveals proximal convoluted renal tubular epithelial cells. Bacteria indicate infection; broad casts indicate renal failure. Cognitive Level: 1, 2 Reference:

5. Glomerular disease associated with lipiduria is known as: A. Chronic glomerulonephritis B. Nephrotic syndrome C. Rapidly progressive glomerulonephritis (RPGN) D. Acute nephritic syndrome

ANS: B Glomerular disease associated with lipiduria is known as nephrotic syndrome. Acute nephritic syndrome is characterized by hematuria, proteinuria, oliguria, azotemia, edema, and hypertension. RPGN exhibits "crescents," leukocyte infiltration, fibrin deposition, and GBM disruptions. Cognitive Level: 1 Reference:

9. Which type of glomerulonephritis may develop as a result of a systemic disease, such as systemic lupus erythematosus, or after an infection? A. Acute glomerulonephritis B. Rapidly progressive glomerulonephritis C. Membranous glomerulonephritis D. Focal segmental glomerulosclerosis

ANS: B Rapidly progressive glomerulonephritis (i.e., crescentic glomerulonephritis) develops after an infection; as a result of systemic diseases, such as lupus or vasculitis; or it may be idiopathic. Acute glomerulonephritis often occurs after β-hemolytic streptococci. Membranous glomerulonephritis is idiopathic in 85% of patients and is associated with immune-mediated diseases in the remaining 15% of cases. Focal segmental glomerulosclerosis may occur as a primary glomerular disease; may be associated with another glomerular disease (e.g., IgA nephropathy); or may occur secondary to other disorders. Cognitive Level: 2 Reference:

8. The causative agent of the clinical diagnosis in question 7 is: A. Vaccination B. β-hemolytic streptococci C. Allergic reaction D. T-cell dysfunction

ANS: B The causative agent is most likely β-hemolytic streptococci, in particular those with M protein in their cell walls. Cognitive Level: 3 Reference:

24. A 35-year-old man presents to his physician with complaints of pain in his spine and large joints that has been progressively worsening over the past 6 months. He also points out that his ears are getting darker in color. He sheepishly reveals that, to conserve water, he does not always flush the toilet after urination, and he has noticed that when he voids, the urine is yellow, but when he comes back later, it has changed to a much darker color. The physician orders a gas chromatography-mass spectrometry analysis on the patient's urine. The results are positive for: A. Tyrosine B. Homogentisic acid C. Melanin D. Catecholamines

ANS: B This patient has alkaptonuria, a rare autosomal recessive disease characterized by excretion of excessive amounts of homogentisic acid not normally present in urine. The urine darkens upon exposure to alkali, air, and sunlight, forming a dark precipitate. The disease is not usually diagnosed until middle age (30 to 40 years old) and presents with arthritis of the spine and large joints, along with ochronosis, or pigmentation in the ears. Cognitive Level: 2 Reference:

7. A 10-year-old female presents to the ED with fever, malaise, nausea, oliguria, and edema of the eyes, knees, and ankles. Her blood pressure is mildly elevated. The creatinine clearance is decreased, with an elevated blood urea nitrogen to creatinine ratio. The clinical history reveals that the child had strep throat several weeks ago and that she appeared to have recovered without incident. Physical Examination Color: Reddish brown Clarity: Cloudy Chemical Examination Sp. Gr. 1.025 pH 6.5 Blood: Moderate Protein: 1000 mg/dL (SSA4+) LE: Positive Nitrite: Negative Glucose: Negative Ketones: Negative Bilirubin: Negative Urobilinogen: 1.0 EU Microscopic Examination 10-20 WBCs 25-50 RBCs Casts: 0-2 Granular/lpf 2-4 RBC 0-2 Hemoglobin The clinical diagnosis for this patient, based on the history and laboratory results, is: A. Minimal change disease B. Nephrotic syndrome C. Acute glomerulonephritis D. IgA nephropathy

ANS: C Acute glomerulonephritis is characterized by increased RBCs, WBCs, and renal tubular epithelial cells, along with RBC and hemoglobin casts. Nephrotic syndrome is characterized by oval fat bodies, free fat globules, and increased casts (i.e., fatty, waxy, renal cells). IgA nephropathy, which involves IgA deposits that can be detected using special stains and microscopy (i.e., immunofluorescence), has variable cellular proliferation. Minimal change disease shows loss of foot processes. Cognitive Level: 3 Reference:

12. The pathogenesis of which systemic disorder involves deposition of a pathologic proteinaceous substance between cells in numerous tissues and organs? A. Diabetes mellitus B. Systemic lupus erythematosus C. Amyloidosis D. IgA nephropathy

ANS: C Amyloidosis is a group of systemic disorders characterized by multiple organ involvement and deposition of amyloid, a proteinaceous substance, between cells in tissues and organs. Systemic lupus erythematosus results in rapidly progressive glomerulonephritis (i.e., crescentic glomerulonephritis). IgA nephropathy is characterized by deposition of IgA in mesangium. Cognitive Level: 1 Reference:

25. Which condition produces a pale urine with a high specific gravity? A. Diabetes insipidus B. Galactosuria C. Diabetes mellitus D. Porphyria

ANS: C Diabetes mellitus produces a pale urine with a high specific gravity. The pale color is due to polydipsia and polyuria, and the high specific gravity is due to the large amount of glucose excreted as a result of hyperglycemia. The renal threshold has been exceeded, resulting in glycosuria. Diabetes insipidus produces copious amounts of urine with a low specific gravity due to the inability to concentrate urine. Galactosuria is the presence of galactose in the urine as a result of an inherited autosomal recessive disorder. Porphyria results in the excretion of porphobilinogen in the urine. Cognitive Level: 2 Reference:

28. What is the distinguishing clinical feature of the type of porphyria that results in the accumulation of porphyrins? A. Neurologic symptoms B. Mental retardation C. Photosensitivity D. Nephropathy

ANS: C Porphyrias manifest differently. When porphyrins are the major accumulation product, the distinguishing clinical feature is photosensitivity. Disorders resulting in the accumulation of porphobilinogen and d-aminolevulinic acid present with neurologic symptoms. Cognitive Level: 1 Reference:

16. Vitamin D-resistant rickets is due to the inherited dominant sex-linked disorder: A. Renal tubular acidosis (RTA) B. Renal glycosuria C. Renal phosphaturia D. Renal cystinosis

ANS: C Renal phosphaturia is a hereditary disorder characterized by phosphaturia arising from the inability of the distal tubules to reabsorb inorganic phosphorous. RTA is characterized by tubular inability to secrete adequate H+ despite a normal GFR. Cystinosis is an inherited autosomal recessive disorder that causes renal tubular dysfunction and cystinosis. Glycosuria is the presence of glucose in the urine, a common finding in diabetes mellitus. Cognitive Level: 1 Reference:

18. An active, vibrant, 85-year-old female is brought to the clinic by her daughter, who states that her mother has been experiencing mental confusion and distress. No other signs or symptoms are reported. The physical examination notes no abnormalities; temperature, pulse, and blood pressure all are normal. A urinalysis is ordered, which produces the following results: Physical Examination Color: Amber Clarity: Cloudy Chemical Examination Sp. Gr. 1.025 pH 5.5 Blood: Small Protein: Trace LE: Positive Nitrite: Positive Glucose: Negative Ketones: Negative Bilirubin: Negative Urobilinogen: 1.0 EU Microscopic Examination 30-40 WBCs 10-25 RBCs 2-4 Transitional epithelial cells 4+ Bacteria Based on these results, the patient's confused mental state and anxiety most likely are due to: A. Pyelonephritis B. Glomerulonephritis C. Cystitis D. Age-related dementia

ANS: C The urinalysis results indicate a UTI: positive LE and nitrites, and increased WBCs and bacteria in the microscopic examination. In the elderly, a common initial and possibly the only sign of a UTI is mental confusion or distress. Cognitive Level: 3 Reference:

23. Which of the following inherited diseases gives the urine a characteristic mousy or musty odor? A. Maple syrup urine disease B. Cystinosis C. Alkaptonuria D. Phenylketonuria

ANS: D A mousy or musty odor in the urine is indicative of Phenylketonuria. PKU is excess excretion of phenylpyruvic acid and its metabolites in urine because of an inherited metabolic disorder; if the disorder goes untreated, it results in mental retardation. Alkaptonuria is a rare autosomal recessive disease characterized by excretion of excessive amounts of homogentisic acid not normally present in urine. The urine darkens upon exposure to alkali, air, and sunlight, forming a dark precipitate. Cystinosis results in excretion of the amino acid cystine. Cognitive Level: 2 Reference:

4. Glomerular damage characterized by hematuria, proteinuria, oliguria, azotemia, edema, and hypertension is referred to as: A. Nephrotic syndrome B. IgA nephropathy C. Chronic glomerulonephritis D. Acute nephritic syndrome

ANS: D Acute nephritic syndrome is characterized by hematuria, proteinuria, oliguria, azotemia, edema, and hypertension. Nephrotic syndrome is characterized by increased permeability of glomeruli to plasma proteins, leading to heavy proteinuria (3.5 g/day or more); other features include hypoproteinemia, hyperlipidemia, lipiduria, and edema. IgA nephropathy involves IgA deposits that can be detected using special stains and microscopy (i.e., immunofluorescence). Chronic glomerulonephritis is a slow process, developing over many years, that has varying presentations, which may include edema, hypertension, cerebral or cardiovascular conditions, proteinuria, and azotemia. Cognitive Level: 1 Reference:

2. What type of morphologic change results in the accumulation of a homogeneous eosinophilic extracellular material in the glomeruli? A. Cellular proliferation B. Leukocyte infiltration C. Glomerular basement membrane thickening D. Hyalinization of glomeruli

ANS: D Hyalinization of glomeruli is characterized by an accumulation of homogeneous, extracellular material in the glomeruli. Leukocyte infiltration occurs as a result of a local chemotactic response. Cellular proliferation occurs in the glomerular tuft and is characterized by an increase in endothelial cells, mesangial cells, and epithelial cells. Glomerular basement membrane thickening includes any process leading to enlargement of the basement membrane. Cognitive Level: 1 Reference:

13. Ischemic acute tubular necrosis (ATN) may result from all of the following conditions except: A. Bacterial infection B. Severe burns C. Crush injuries D. Renal glycosuria

ANS: D Ischemic ATN occurs after a hypotensive event, such as shock, that results in decreased renal perfusion followed by ATN. The three principal causes of ATN are sepsis, shock, and trauma. Sepsis can result from severe burns and bacterial infections. Trauma includes crush injuries. Cognitive Level: 3 Reference:

17. The four types of renal tubular acidosis involve all of the following pathogeneses except: A. Impaired ability to exchange sodium for potassium and hydrogen B. Decreased proximal tubular reabsorption of bicarbonate C. Inability to maintain the hydrogen ion gradient and inability to increase tubular ammonia secretion D. Increased secretion of calcium carbonate, resulting in hypocalciuria

ANS: D The four types of RTA include the pathogeneses listed in options A, B, and C. A compensation mechanism for type I RTA involving inability to maintain the H+ gradient and inability to increase tubular ammonia secretion to compensate does so by removing calcium carbonate from bone to buffer the retained acids, resulting in the development of osteomalacia, hypercalcemia, and hypercalciuria. Cognitive Level: 1 Reference:

11. Based on your answer to question 10, the patient is most likely suffering from idiopathic onset of: A. Nephritic syndrome B. IgA nephropathy C. Glomerulosclerosis D. Nephrotic syndrome

ANS: D The typical presentation of membranous glomerulonephritis is sudden onset of nephrotic syndrome. The UA chemical analysis detects large amounts of protein, and the microscopic examination reveals waxy, fatty, renal cell casts and oval fat bodies. Cognitive Level: Reference:

10. A 50-year-old male presents to his physician, complaining of having had edema, general malaise, fatigue, and anorexia for the past several weeks. The physical examination reveals no other abnormal presentations, except a reported weight gain of 20 pounds in the past 3 days. The clinical history reports no previously existing pathologic conditions. The blood pressure, pulse, and temperature are normal. Blood work and a UA are ordered. The findings include an elevated blood urea nitrogen to creatinine ratio, a decreased creatinine clearance, and a decreased serum protein. Physical Examination Color: Amber Clarity: Cloudy White foam noted Chemical Examination Sp. Gr. 1.025 pH 7.0 Blood: Negative Protein: 100 mg/dL (SSA 4+) LE: Negative Nitrite: Negative Glucose: Negative Ketones: Negative Bilirubin: Negative Urobilinogen: 1.0 EU Microscopic Examination 0-2 WBCs Casts: 3-6 Hyaline/lpf 2-4 Waxy 0-2 Fatty 0-2 Renal cell Oval fat bodies Based on the test results, this clinical presentation and UA report are typical for which of the following conditions? A. Acute glomerulonephritis B. Chronic glomerulonephritis C. Rapidly progressive glomerulonephritis D. Membranous glomerulonephritis

ANS: D The typical presentation of membranous glomerulonephritis is sudden onset of nephrotic syndrome. The UA chemical analysis detects large amounts of protein, and the microscopic examination reveals waxy, fatty, renal cell casts and oval fat bodies. Cognitive Level: 3 Reference:

26. Neonatal screening tests are routinely performed for which condition to prevent mental retardation through dietary restrictions? A. Galactosemia B. Maple syrup disease C. Phenylketonuria D. Cystinosis E. A, B and C

ANS: E Neonatal screening tests typically include testing for maple syrup disease, galactosemia, and PKU. If left untreated, these conditions lead to mental retardation. Cystinosis is evident during the first year of life, because patients show slow growth, rickets, polyuria, polydipsia, dehydration, and acidosis. By age 2, cystine crystals may result in photosensitivity, because the crystals abnormally accumulate in the cornea. Treatment (i.e., renal dialysis or kidney transplantation) is necessary because of the extensive kidney damage. Cognitive Level: 1 Reference: