Nephrology Flashcards
Evaluation of the kidneys for masses, scarring, and hydronephrosis is best done with this imaging type
Ultrasound
Acute kidney injury severity is classified by ..
Increased serum creatinine and decreased GFR
What would be seen on an ultrasound in chronic kidney disease?
Decreased kidney size
Bun-to-creatinine ration increases with these two things
Renal failure
CHF
Symptom that is shared by SIADH and diabetes insipidus
Excessive thirst
Bun-to-creatinine ration decreases with these two things
Starvation
Liver failure
Urinary sediment findings in these acute renal failures:
1.) Prerenal
2.) Intrarenal
3.) Postrenal
1.) Prerenal = Normal
2.) Intrarenal = Abnormal casts and debris
3.) Postrenal = Normal
Vitamin D deficiency is significant in identifying these three conditions
Osteoporosis/penia
Rickets
Liver disease
BUN normal range
8-18 mg/dL
Nephrolithiasis should be evaluated with this type of imaging
CT-KUB without contrast
In the diagnosis of CKD, what four things would be seen in a urinalysis?
Proteinuria
Casts
Microalbuminuria
Electrolytes
Reasons (2) for decreased eGFR levels
Impaired kidney function
Conditions causing decreased GFR (e.g. CHF, cirrhosis with ascites, shock, dehydration)
Reasons (3) for ADH to be increased
SIADH
Nephrogenic diabetes insipidus caused by primary renal diseases
Dehydration
Three functions of ADH
Decrease urine output
Decrease sweating
Increase BP by retaining fluid
BUN-to-creatinine ration >20:1 suggests …
Dehydration
(but also increases with CHF and renal failure)
The key to SIADH is that the hyponatremia is a result of …
Excess of water (rather than a sodium deficiency)
Reason for ADH to be decreased
Neurogenic (central) diabetes insipidus
Urine specific gravity findings in these acute renal failures:
1.) Prerenal
2.) Intrarenal
3.) Postrenal
1.) Prerenal = Increased
2.) Intrarenal = Normal
3.) Postrenal = Varies
In ultrasound of chronic kidney disease you would see this change in size
Reduced size
Leading cause of cancer death in males in US (2nd worldwide)
Prostate cancer
Which, pre, intrinsic, or post renal azotemia is most common?
Pre-renal
True or false. Ultrasounds are nonspecific for solid renal masses and moderate sensitivity for stones.
True
Further imaging with CT usually required
Reason for decreased serum osmolality
SIADH
Microalbuminuria is an early indicator of …
Renal disease
How is a creatinine clearance test performed
24 hour urine collection
Serum creatinine level
Lab test for cause of glomerulonephritis
ANA - antinuclear antibodies
Causes of intrinsic renal azotemia
Acute tubular necrosis
In diagnosis of CKD, what would be seen on a CMP?
Azotemia
Increased ammonia
Increased uric acid
Decreased active vitamin D
Hyperkalemia
Hyperphosphatemia
Hypermagnesemia
Hyponatremia
Hypocalcemia
Decreased GFR
Increased creatinine
Increased BUN
Is serum osmolality directly or inversely related to serum water levels?
Inversely
GFR normal values for men and women
MEN: 115-125 mL/min
WOMEN: 90-100 mL/min
Serum creatinine normal ranges for men and women
MEN: 0.6-1.2 mg/dL
WOMEN: 0.5-1.1 mg/dL
Reason for increased urine osmolality
SIADH
Nephritic syndrome is also known as …
Glomerulonephritis
Four signs of CKD
CHF
HTN
Edema
Weight gain
(chew!)
This test is helpful when the urine output is low and you suspect acute kidney disease
Urine sodium
Acute tubular necrosis is associated with what finding in the urine?
Muddy brown casts
For most people, transient microscopic hematuria is of little concern. What is the exception and why?
Old people
Blood in urine = risk of malignancy
Renal stones greater than this size warrant referral to urology
10mm (if hasn’t been passed in four weeks)
BUN/Cr >20:1 is suggestive of …
Pre-renal azotemia
Renin is an enzyme (and a hormone) that is released by the …
Kidney
Most common test for ADH levels
Serum ADH (blood draw)
Cystoscopy is contraindicated in these two kinds of patients
Febrile patients with UTIs
Patients with severe coagulopathy
Nephrotic syndrome is characterized by …
Large protein losses in the urine
True or false. GFR changes with age, sex, race, and body size.
True
This hormone is made in the kidney and stimulates bone marrow to increase RBC production
Erythropoietin (EPO)
Reasons (2) for increased serum osmolality
Dehydration
Diabetes insipidus
Contraindications (5) for CT angiography
Pregnancy
Unstable vitals
Kidney problems
Allergies
Severe diabetes
This view is useful in visualizing calcifications anywhere along the renal tract
KUB - kidneys, ureters/urethra, bladders
Nuclear testing measures this
Function!
BUN-to-creatinine ration
10:1 - 20:1
eGFR evaluates the degree of …
Kidney function/impairment
CKD severity is classified by …
eGFR
In ultrasound of acute kidney injury you would see this change in size
None! (not for acute anyway)
Normal value for eGFR
> 60 mL/min/1.73m2
The most important noninvasive test in the initial workup of acute kidney injury
Urinalysis
Is ADH more likely to be released from the pituitary in a state of overhydration or dehydration?
Dehyrdration
BUN:Cr ratio in postrenal azotemia
Initially >20:1 then switches to <20:1
Hyperuricemia is an independent risk factor for …
Gout
What might be seen on ultrasound in postrenal azotemia?
Hydronephrosis/Dilated bladder/Urinary retention
Uric acid in the urine is called …
Uricosuria
Is it preferable to have a high or low GFR?
High GFR is better
Most common cause of postrenal azotemia
Any obstruction of urinary tract
Erythropoietin testing is used in the differential diagnosis of these two conditions
Anemia
Polycythemia
Define azotemia
Build up of urea, uric acid, creatinine, and ammonia in the blood
Plasma renin assay blood test measures …
Enzyme ability to convert angiotensinogen to angiotensin 1 and is limited by the availability of the angiotensinogen.
Reason for decreased urine osmolality
Diabetes insipidus
Nephrotic syndrome is most commonly caused by …
Diabetes
Definition of chronic kidney disease
Urinary albumin excretion of 30+ mg/day
OR
eGFR <60 for three or more months (that’s how you know it’s not acute)
Does GFR increase or decrease with age?
Decrease
The examination of choice for urinary tract imaging is …
CT
Kidney appearance on ultrasound in acute kidney injury
Normal renal size
Glucosuria in the absence of hyperglycemia is called …
Renal glucosuria
At the first sign of microalbuminuria in a diabetic they must be placed on this medication
ACE inhibitor
Definition of acute kidney injury
Abrupt (within 48 hours) reduction in kidney function based on an elevation in serum creatinine levels
All patients with kidney disease (acute or chronic) should have their …. from the serum creatinine evaluated.
Glomerular filtration rate
True or false. Biopsy is contraindicated in pregnancy and advanced age
False
Normal vitamin D (D2 + D3) levels
25-80 ng/mL
BUN levels are directly related to …
Metabolic function of the liver
Excretory function of the kidney
In the diagnosis of CKD, what three things would be seen in a CBC?
Normochromic, normocytic anemia
Thrombocytopenia
Increased bleeding time
True or false. All patients with prostate cancer have increased PSA levels.
False.
1 in 4 have normal PSA levels
Acute kidney injury laboratory findings
Hyponatremia
Hypocalcemia
Metabolic acidosis
Hyperkalemia
Elevated BUN levels
Elevated plasma creatinine
The best measure of renal function is …
GFR
Proteinuria is suggestive of this type of kidney condition
Nephrotic syndrome
Biopsy is contraindicated in these two conditions
Severe hypertension (>170 systolic, uncontrolled)
Active renal or perineal infection
Cause of pre-renal azotemia
Any cause of reduced renal blood flow
(CHF, dehydration, shock, sepsis)
Reason for presence of albumin in urine
Diabetes mellitus
How to be sure proteinuria is transient rather than persistent?
Two protein free urinalyses
Is serum creatinine directly or inversely related to GFR?
Inversely
In SIADH will serum Na/osmolality be increased or decreased? And will urine osmolality be increased or decreased?
Serum Na/osmolality = DECREASED
Urine osmolality = INCREASED
Grading system used in evaluating the prognosis of men with prostate cancer
Gleason grading scale
Labs for glucosuria
Complete UA (with microscopy)
Serum glucose
Serum urea nitrogen
Creatinine
USPSTF recommendations for prostate cancer screening
Age 55-69 only if patient wants it (shared decision making)
Category C
The most important indicator of renal disease in urine is
Proteinuria
In the diagnosis of CKD, what would be seen on a lipid profile?
Hyperlipidemia
Compare and contrast neurogenic and nephrogenic diabetes insipidus
Neurogenic results from inadequate ADH secretion
Nephrogenic results from the kidney being unresponsive to ADH stimulation
In DIABETES INSIPIDUS will serum Na/osmolality be increased or decreased? And will urine osmolality be increased or decreased?
Serum Na/osmolality = INCREASED
Urine osmolality = DECREASED
The most common way to measure a person’s GFR is …
Creatinine clearance
BUN:Cr ratio in intrinsic renal azotemia
Less than 20:1
Nuclear medicine is used to evaluate for this type of disease
Metastatic
In DEHYDRATION will serum Na/osmolality be increased or decreased? And will urine osmolality be increased or decreased?
Serum Na/osmolality = INCREASED
Urine osmolality = INCREASED
Persistent hematuria is mostly caused by these three cancers
Bladder
Renal
Prostate (least common)
All diabetics older than 12 should be screened annually for this …
Microalbuminuria
The gold standard for imaging vascular malformations is
CTA (CT + angiography)
Nephritic syndrome is characterized by …
Inflammation (of the capillary loops)