12.5 - 12.7: Nephrolithiasis and Chronic Renal Failure

Question 1

UTIs are defined as an infection of what three organs?

Answer 1

Urethra, Bladder, or Kidney

Question 2

True or false: sex is a risk factor for UTIs

Answer 2

True

Question 3

What are the s/sx of cystitis? Are systemic signs usually present?

Answer 3

• Dysuria, frequency, urgency, and suprapubic pain

- Usually no systemic signs

Question 4

What will a UA show with cystitis?

Answer 4

Cloudy urine with more than 10 WBC/hpf

Question 5

What will a urine dipstick test show with a cystitis?

Answer 5

Positive leukocyte esterase and nitrites

Question 6

What will a culture show with cystitis?

Answer 6

More than 100,000 colony forming units

Question 7

What are the 5 bacteria that cause UTIs? Which is most common?

Answer 7

• E.coli
• Staph saprophyticus
• Klebsiella pneumoniae
• Proteus mirabilis
• Enterococcus faecalis

Question 8

Ammonia scented urine = what infx?

Answer 8

Proteus mirabilis

Question 9

What is sterile pyuria? What does this suggest?

Answer 9

Pyuria with negative urine cultures

Suggests urethritis d/t chlamydia or gonorrhea

Question 10

What is a major, physiological risk factor for the development of pyelonephritis?

Answer 10

Vesicoureteral reflux

Question 11

What are the s/sx of pyelonephritis? (4)

Answer 11

• Fever
• Flank pain
• WBC casts
• Leukocytosis

Question 12

What causes the flank pain with pyelonephritis?

Answer 12

Sensitization of the nerves that innervate the capsule of the kidney

Question 13

What are the three most common pathogens of pyelonephritis?

Answer 13

• E.coli
• Klebsiella
• Enterococcus faecalis

Question 14

What is chronic pyelonephritis, and what causes it?

Answer 14

Interstitial fibrosis and atrophy of tubules d/t multiple bouts of acute pyelonephritis, usually coincides with vesicoureteral reflux

Question 15

What is the characteristics scarring pattern in the kidneys of vesicoureteral reflux?

Answer 15

Scarring of upper and lower poles

Question 16

What are the histological characteristics of atrophic tubules 2/2 chronic pyelonephritis?

Answer 16

Eosinophilic proteinaceous material within the atrophic tubules, that appear like the colloid of the thyroid

“thyroidization”

Question 17

What is thyroidization?

Answer 17

Eosinophilic proteinaceous material within the atrophic tubules, that appear like the colloid of the thyroid

Question 18

What types of casts are seen in the urine with chronic pyelonephritis?

Answer 18

Waxy casts

Question 19

What, very generally, are the two risk factors for the development of nephrolithiasis?

Answer 19

• High concentration of solute

- Low urine volume

Question 20

How fast are stones passed?

Answer 20

Within a few hours

Question 21

What is the most common type of renal calculi?

Answer 21

Ca oxalate and/or Ca phosphate

Question 22

What are the causes of Ca oxalate renal stones?

Answer 22

Idiopathic hypercalciuria, but also hypercalcemia and related causes

Question 23

What GI disease tends to produce Ca oxalate renal calculi? Why?

Answer 23

• Crohn’s disease

- Damage to the enterocytes increases oxalate reabsorption, leading to Ca crystallization

Question 24

What is the treatment for Ca oxalate crystals? Why?

Answer 24

HTZ–Ca sparing diuretic

Question 25

What diuretics are absolutely contraindicated with Ca oxalate stones? Why?

Answer 25

Loop diuretics, since these will increase tubular Ca levels

Question 26

What is the most common cause of ammonium magnesium phosphate renal calculi? Why?

Answer 26

Infection with urease positive organisms (e.g. proteus vulgaris or Klebsiella) This leads to alkalinization of the urine

Question 27

What is the treatment for ammonium magnesium phosphate renal calculi?

Answer 27

Surgical removal of stone and eradication of pathogen

Question 28

What is the classic shape of ammonium magnesium phosphate renal calculi?

Answer 28

Staghorn

Question 29

What is significant about uric acid crystals in terms of detection?

Answer 29

Radiolucent

Question 30

What are the only radiolucent renal calculi?

Answer 30

Uric acid crystals

Question 31

What are uric acid renal calculi associated with?

Answer 31

- Hot climate - acidic pH - Gout - Myeloproliferative disease

Question 32

Why are uric acid stones associated with myeloproliferative diseases?

Answer 32

Increased cellular turnover leads to increase in uric acid

Question 33

What is the treatment for uric acid stones?

Answer 33

Hydration and alkalinization of the urine (K HCO3) | -Allopurinol with gout

Question 34

In whom are Cysteine crystals usually seen? Why?

Answer 34

Children d/t cystinuria

Question 35

What is the defect in hereditary cystinuria?

Answer 35

Genetic defect of tubules that results in decreased reabsorption of cystine (and COAL amino acids)

Question 36

What are the characteristics of cystine calculi?

Answer 36

Staghorn calculi

Question 37

What is the treatment for cysteine renal calculi?

Answer 37

Hydration and alkanization of the urine

Question 38

What is a staghorn calculus? What are the two types calculi that forms these?

Answer 38

Renal calculus that involves the entire calyx Cysteine AMP stones

Question 39

What types of stones are seen with alkaline urine? Acidic?

Answer 39

Alkaline = ammonium, magnesium, phosphate Acidic = uric acid stones

Question 40

End stage kidney failure results from damage to what part of the kidney?

Answer 40

Any-glomerular, tubular, inflammatory or vascular insults

Question 41

What are the three most common causes of ESRD?

Answer 41

- DM - HTN - Glomerular disease

Question 42

Why does uremia cause platelet dysfunction?

Answer 42

Uremia Inhibits platelet adhesion aggregation

Question 43

What, generally, is uremia?

Answer 43

Increased nitrogenous waste products within the blood

Question 44

What are the s/sx of uremia? (heart, hematological, CNS, skin)

Answer 44

- Pericarditis - Platelet dysfunction - Encephalopathy with asterixis - Deposition of urea crystals in the skin

Question 45

What is asterixis?

Answer 45

- a tremor of the hand when the wrist is extended - caused by abnormal function of the diencephalic motor centers in the brain, which regulate the muscles involved in maintaining position.

Question 46

What are the latin roots of asterixis?

Answer 46

``` a = not Asterixis = fixed position ```

Question 47

What, generally, causes asterixis?

Answer 47

- Metabolic encephalopathy - Acute respiratory failure - Hepatic encephalopathy

Question 48

Why is the HTN with uremia?

Answer 48

Retention of salt and water

Question 49

What is the metabolic disturbance common to uremia?

Answer 49

Hyperkalemia with metabolic acidosis

Question 50

What is the hematological abnormality with uremia? Why?

Answer 50

Anemia d/t loss of EPO

Question 51

What cells produce EPO?

Answer 51

Renal peritubular, interstitial cells

Question 52

Why is there hypocalcemia seen with uremia? (2)

Answer 52

- Decreased 1-alpha-hydroxylase | - Hyperphosphatemia will bind Ca

Question 53

What are the cells that contain 1-alpha-hydroxylase?

Answer 53

Renal peritubular, interstitial cells

Question 54

What causes the osteitis fibrosa cystica with renal failure?

Answer 54

Loss of Ca leads to increased PTH, which causes bone resorption

Question 55

What causes osteomalacia in renal dysfunction?

Answer 55

Cannot mineralize the osteoid made by the osteoblasts

Question 56

What is the main cause of osteoporosis with ESRD?

Answer 56

Leaching of Ca from bone over time d/t acidosis and the use of bone as buffer

Question 57

What are the two treatment options for ESRD?

Answer 57

- Dialysis | - Renal transplant

Question 58

What happens to the kidneys with chronic dialysis?

Answer 58

Shrunken kidneys with cysts

Question 59

Patients who are on chronic dialysis are at an increased risk for what cancer?

Answer 59

Renal cell carcinoma

Question 60

How can you differentiate cysts 2/2 PKD and from dialysis in ESRD?

Answer 60

- PKD = large kidneys with cysts | - ESRD = small, fibrotic kidney with cysts