Nep Flashcards
_____ is defined as a rapid rise in blood urea nitrogen (BUN) or creatinine over a period of several hours to days
Acute renal failure (ARF), or better referred to as acute kidney injury (AKI),
_____ can be used interchangeably with the term renal insufficiency; literally,
azotemia means the buildup of azole groups or nitrogen in the blood.
Azotemia
____describes a syndrome of very severe renal failure in which there is the need for
dialysis to save life
Uremia
T or F
Uremia does not necessarily mean the same thing as chronic renal failure
AKI
____means decreased perfusion of the kidney.
_____ means decreased drainage from the kidney or decreased forward flow of urine.
____means there is a tubular or glomerular problem, and the kidney itself is defective.
Prerenal azotemia
Postrenal azotemia
Intrarenal
The BUN can be falsely low when there is ______
liver disease, malnutrition, or SIADH.
______ is our closest approximation of glomerular filtration rate (GFR) without the use of more cumbersome testing such as the clearance of inulin.
Creatinine clearance
Causes of pre-renal azotemia
- hypovolemia on any basis (dehydration, burns, poor oral intake, diuretic, vomiting, diarrhea, sweating, hemorrhage),
- hypotension on any basis (septic shock, cardiogenic shock, anaphylactic shock),
- third spacing of fluids such as peritonitis, osmotic diuresis,
- low aldosterone states such as Addison disease.
The first clue to the diagnosis of prerenal azotemia is a ______
BUN:creatinine ratio of 20:1.
Pre-renal azotemia
There is also a low _______
This results in a very high ______
urine sodium and low fractional excretion of sodium (FeNa <1%).
urine osmolality as well.
Pre-renal azotemia
Concentrated urine has a_____ and ______
high specific gravity (>1.010) and
a high urine osmolality (>500).
T or F
Low albumin states also lead to decreased renal perfusion
T
Pre-renal Azotemia
There is markedly diminished renal perfusion because of the obstruction in the renal artery.
Renal artery stenosis
Renal artery stenosis
This effect is greatly exaggerated with the use of ____which markedly diminish renal perfusio n
ACE inhibitors,
Pre-renal Azotemia
______ is renal failure based entirely on the presence of hepatic failure. The kidneys are normal. The etiology of the rise in BUN and creatinine is thought to be from
an intense vasoconstriction of the afferent arteriole, resulting in decreased renal perfusion
Hepatorenal syndrome
______is diagnostic of hepatorenal syndrome
No improvement in renal failure after 1.5 L of colloid,
like albumin,
HRS
____ and ____may be beneficial in hepatorenal syndrome. However, the best treatment is liver transplantation.
Midodrine,
an alpha agonist, and octreotide
ACE inhibitor–induced renal failure is from
vasodilation of the efferent arteriole
Despite the ability of ACE inhibitors to potentially worsen renal function, the overall effect on the kidney is _____
diminishing the rate of progression to uremia and renal failure
ACE inhibitors and angiotensin receptor blockers decrease ______
hypertension inside the glomerulus.
ACE inhibitors decrease proteinuria by_____
35–45%.
Creatinine will only begin to rise when you have lost at least_____
70–80% of renal function.
BUN Crea ration early and late post renal azotemia
Initially, the BUN and creatinine will elevate in a ratio of 20:1 as it does with prerenal azotemia.
then the BUN:creatinine ratio will lower to closer to
10:1, such as that seen in acute tubular necrosis (ATN).
About 85% of acute renal failure is secondary to _____
intrinsic renal disease such as ATN.
Three Phases of intrinsic renal failure (Not Seen in All Patients)
• ________—This is the time between the acute injury and the onset of renal failure.
• ________(<400 mL per 24 hours) or anuric (<100 mL per 24 hours)
•_____—This is a diuretic phase when all the water not previously excreted will now leave the body in a vigorous polyuria.
Prodromal
Oliguric
Postoliguric
Intrinsic renal failure
The initial clue is a BUN:creatinine ratio close to____
10:1.
Further clues to the diagnosis of ATN are a
1
2
3
high urine sodium (>40),
high fractional excretion of sodium (>1%),
and low urine osmolality (<350).
Diagnosis:
Urine osmolarity: >500
Urine Na+: <20
FeNa+: <1%
Urine sediment: Scant
Pre-renal azotemia
Diagnosis:
Urine osmolarity: <350
Urine Na+: >40
FeNa+:>1%
Urine sediment: Full (brownish pigmented
granular casts, epithelial casts)
ATN
T or F
Diuretics such as furosemide or mannitol do not reverse the ATN
T
T or F
Hydration can prevent contrast-induced renal failure, but it does not reverse it once it occurs
T
ATN
Another form of ineffective therapy is ____ at low dose to increase renal perfusion
dopamine
_____ accounts for 10–15% of intrinsic renal failure. It can be distinguished from other causes of renal failure by the presence of fever and rash on physical
examination and many WBCs, occasionally eosinophils.
Allergic interstitial nephritis (AIN)
Meds causing AIN
can be from penicillins, cephalosporins,
sulfa drugs, allopurinol, rifampin, and quinolones
It is important to remember that any sulfa drug can cause allergic reactions. Besides antibiotics, other examples of sulfa drugs are diuretics such as ________
thiazides, furosemide, or acetazolamide.
The most common infections to result in AIN are ______
leptospirosis, legionella, CMV, rickettsia, and streptococci.
____ is present in 80% of those with AIN.
_____ is present in 25–50% of patients
Fever
Rash
The best initial test for AIN is a ______
urinalysis (UA) looking for white cells.
The most accurate test for urine eosinophils is a ______
Hansel stain or Wright stain of the urine
Massive hemoglobinuria severe enough to cause renal failure is generally only caused by an ______
ABO
incompatibility
The most important test when there has been a severe crush injury or seizure and the rhabdomyolysis is potentially life threatening is an ______
EKG or potassium level
The best initial test that is specific for rhabdomyolysis is a _____
UA in which you find a dipstick that is positive for blood but in which no red cells are seen
Rhabdomyolysis is confirmed with a markedly elevated _____
serum CPK level
CPK
In order for nephrotoxicity to occur, the level must be enormously elevated into the _____ range with a normal value generally <500 or less.
10,000 to 100,000
Rhabdomyolysis
If there are EKG abnormalities from the hyperkalemia the best initial therapy is ______
calcium chloride or gluconate
Rhabdomyolysis
_____ may help prevent the precipitation of the pigment in the tubule
Alkalinizing the urine with bicarbonate
_____ proteins, such as in myeloma, also cause tubular damage.
Bence-Jones
____ is most prominently a cause of nephritic syndrome, however, not tubular damage
Myeloma
The most common cause of hyperoxaluria resulting in acute renal failure is from_____ in a suicidal person who ingests antifreeze
ethylene glycol overdose
ethylene glycol overdose
The diagnosis is confirmed by finding _____
oxalate crystals on a UA. Oxalate crystals are shaped like envelopes
Acute ethylene glycol overdose is treated with _____ to prevent the formation of the toxic metabolite of ethylene glycol, which is oxalic acid.
fomepizole infusion
Chronic hyperoxaluria and kidney stones can be caused by _____
Crohn’s disease because of fat and
calcium malabsorption.
What is given to prevent uric acid nephropathy. in pts with tumor lysis syndrome
Allopurinol treatment with alkalinization of urine markedly reduces the risk of uric acid nephropathy
Calcium precipitates in the kidney tubule, forming stones. In addition, hypercalcemia can lead ________ and ____
to distal RTA and nephrogenic diabetes insipidus
The most common cause of hypercalcemia is_____
primary hyperparathyroidism.
The most common toxins to be associated with renal insufficiency and ATN are_____
NSAIDs, aminoglycosides, cephalosporins, contrast agents, amphotericin, chemotherapy such as cisplatin,
radiation effect, heavy metals such as lead, mercury, or gold, and cyclosporine
The difference between the basis of allergic interstitial nephritis and direct toxins is that allergic nephritis
_______
occurs with the first dose and is associated with fever, rash, joint pain, and eosinophils in both
blood and urine.
______is the least nephrotoxic compared with gentamicin and amikacin.
Tobramycin
_____ generally takes 5–10 days of administration to result in toxicity
Aminoglycoside toxicity
Renal failure due to aminoglycosides is
frequently _______
non-oliguric (K+ levels not elevated)
The ability of antibiotics to kill bacteria is associated with
the peak level, but the likelihood of toxicity is associated with the _______
trough level
Aminoglycoside-related nephrotoxicity is estimated to
be between _____ of all drug-induced nephrotoxicity and is usually reversible.
10–20%
This medication is associated with renal insufficiency as well as distal renal tubular acidosis.
Amphotericin B.
Labs of Amphotericin B toxicity
It is expected that after several days or weeks of amphotericin use, the patient will develop a high creatinine as well as a decreased magnesium, bicarbonate, and potassiumlevel.
What is the possible etiology?
patient who undergoes a vascular catheter procedure such as angioplasty who develops renal failure several days later
Atheroembolic Disease
The BUN and creatinine may be up in a 20:1 ratio, such as in prerenal azotemia, because the
hypertonicity of the agent provokes an intense vasospasm of the afferent arteriol
Radiocontrast material for CT scanning
____ is associated with renal failure in addition to its toxicity on the pancreas
Pentamidine
____is a protease inhibitor that results in renal failure usually from the drug precipitating out in the kidney tubules
Indinavir
NSAIDs are a frequent cause of renal failure. NSAIDS cause renal failure by several mechanisms:
- Interstitial nephritis
- Direct toxic effect on the tubules
- Papillary necrosis
- Inhibition of vasodilatory prostaglandins in the afferent arteriole
- Membranous glomerulonephritis
_____occurs in patients with a history of sickle cell disease, diabetes, urinary obstruction, or chronic pyelonephritis
Acute papillary necrosis
Acute papillary necrosis SSx
The presentation is with the sudden onset of flank pain, hematuria, pyuria, and fever.
The most accurate diagnostic test for papillary necrosis
is a_____
CT scan. The CT scan will show “bumpy” contours in the renal pelvis where the papillae have sloughed off.
In those patients with significant underlying renal disease who have an unavoidable radiologic procedure requiring contrast, you must ____
hydrate with 1–2 liters of normal saline over 12
hours before the procedure
______have also been shown to decrease the risk of renal failure in CIN
Bicarbonate and N-acetyl cysteine
___ and ______ cause glomerular disease and are certainly the most common causes of nephrotic syndrome and end stage renal disease
Diabetes and hypertension
All forms of GN can be characterized by _____
edema, hematuria, red cell casts, and hypertension
The edema of GN is found first in areas of low tissue tension, such as the______
periorbital area or the scrotum
The most important distinction between GN and nephrotic syndrome is_____
the degree of proteinuria.
GN is also characterized by modest amounts of protein in the urine with the daily total being _____ per 24 hours, although by definition nephrotic syndrome does not begin until there are ____ grams per 24 hours
<2 grams
> 3.5
However, the single most important test
to diagnose GN is the______
renal biopsy
Causes of Glomerulonephritis Disease Spectrum
Vascular disease
Wegener granulomatosis Churg-Strauss syndrome Henoch-Schönlein purpura Polyarteritis nodosa Thrombotic thrombocytopenic purpura (TTP) Hemolytic uremic syndrome (HUS) Cryoglobulinemia
Causes of Glomerulonephritis Disease Spectrum
Glomerular Disease
Goodpasture syndrome Postinfectious glomerulonephritis Henoch-Schönlein purpura SLE Idiopathic rapidly progressive glomerulonephritis Alport syndrome Diabetes and hypertension (most common causes) Amyloid
______ is characterized by systemic vasculitis that most often involves the kidney, lung, and upper respiratory tract such as the sinuses or middle ear
Wegener granulomatosis (WG)
Laboratory abnormalities in WG are _____
elevated ESR, anemia, and leukocytosis. Rheumatoid factor is positive in 50%.
The best initial test that is specific for WG is the ____
anti-proteinase-3 antibody, which is also known as cytoplasmic antineutrophil cytoplasmic antibody, or C-ANCA.
The most accurate test for WG is a_____
biopsy of the kidney, nasal septum, or lung looking for
granulomas
______ characterized by a history of asthma, eosinophilia, and other atopic diseases. The characteristic diagnostic tests are the elevated eosinophil count and positive P-ANCA or antimyeloperoxidase
Churg-Strauss Syndrome
Churg-Strauss Syndrome
The most accurate test is a______ showing the granulomas and eosinophils.
Treatment is with _______
lung biopsy
glucocorticoids and cyclophosphamide.
______ is an idiopathic disorder of renal and lung disease characterized by a unique antibasement membrane antibody
Goodpasture syndrome (GP)
Unlike Wegener or Churg-Strauss, GP does not affect multiple organs or sites in the body besides the____
lung and the kidney
Goodpasture syndrome (GP)
The best initial test to confirm the diagnosis is the____
level of
antibasement membrane antibodies to type IV collagen
Goodpasture syndrome (GP)
The single most accurate test is a
lung or kidney biopsy.
Goodpasture syndrome (GP)
The biopsy shows _____
linear deposits on immunofluorescence
______is a systemic vasculitis of small- and medium-sized arteries that affects virtually every organ in the body with the exception of the lung
Polyarteritis nodosa (PAN)
PAN
The most accurate diagnostic test is a____, and treatment is with _____
biopsy
cyclophosphamide
and steroids.
_____ presents with mild hematuria that resolves spontaneously in 30% of patients. About 40–50% of patients progress to end stage renal disease
IgA nephropathy
How to distinguish psgn from IgA nephropathy
This is to distinguish it from poststreptococcal
glomerulonephritis, in which the renal involvement occurs 1–2 weeks later or longer
The treatment of IgA nephropathy is difficult. There is no proven effective therapy. Anyone with proteinuria should receive______
ACE inhibitors or angiotensin receptor blockers (ARB).
In addition to group ______ numerous other
infections can be associated with postinfectious glomerulonephritis.
A beta hemolytic streptococci (Streptococcus pyogenes),
The best initial test for PSGN is
the antistreptolysin (ASO) test and the antihyaluronic acid (AHT) test.
The most accurate test for PSGN is the _____
renal
biopsy showing “humps” on electron microscopy.
Renal disease from _____ is associated with chronic hepatitis C or less commonly B.
cryoglobulinemia
Besides the renal disease, cryoglobulinemia is associated with ________
joint pain, neuropathy, and purpuric skin lesions
Cryoglobulinemia is associated with an elevated
_____and low levels of ____ and is confirmed with a test for the cryoglobulins
ESR
complement
The incidence of glomerular involvement in diabetes is directly proportional to the ____
duration of the diabetes
What dse?
Double-stranded DNA levels go up and complement levels go down as a marker of severity in flare-ups of the disease.
SLE
Tx of SLE with Proliferative disease:
Use steroids combined with mycophenolate. Mycophenolate is superior to cyclophosphamide.
_____ is the combination of glomerular disease with congenital eye and ear abnormalities. There is sensorineural hearing loss
Alport syndrome
What type of amyloidosis
Plasma cell dyscrasia causing deposition of protein derived from immunoglobulin
light chains. This may be associated with multiple myeloma
Amyloidosis
Other unique methods of diagnosis are_____
aspirating the abdominal fat pad or taking a sample of
the rectum
AMyloidosis
___ and _____can control protein
production.
Melphalan and prednisone
Nephrotic syndrome is defined as the presence of renal disease sufficient to produce
a level of proteinuria >3.5 grams per 24 hours, hyperlipidemia,
edema, and a
low serum albumin level
Why is there hyperlipidemia in NS
Hyperlipidemia is of unclear etiology but is most
likely from the loss of the lipoprotein markers or signals on the surface of chylomicrons and LDL that lead to the clearance of these lipids from the bloodstream
NS
Hypercoagulable states or thrombophilia develops from the _____
urinary loss of natural anticoagulant
proteins such as antithrombin, protein C, and protein S
NS
If steroids do not work, the next best step in therapy is to add______
cyclophosphamide
or mycophenolate
______is the most common cause of nephrotic syndrome in adults.
FSGS
____ Associated with the use of heroin as well as
HIV. Limited response (only 20–40%) to steroids
Focal-Segmental Glomerulosclerosis (FSGS).
FSGS May progress to end stage renal disease
(ESRD) over_____
5–10 years.
What kind of NS
______Associated with cancer such as lymphoma or breast cancer, and infections such
as endocarditis or chronic hepatitis B or C. Other etiologies are lupus, penicillamine, gold
salts, and NSAIDs
Membranous.
What kind of NS
Most common form in children, although it may
account for 15% of adult disease. NSAIDs have also been associated with nil lesion disease
Nil Lesion (Minimal Change Disease).
EM findings of MCD
Light microscopy is normal and electron microscopy is needed to see fusion of foot processes
Associations of MCD
Hodgkin’s lymphoma has an association with nil
lesion disease.
What NS
Mostly idiopathic, steroid-resistant type of nephrotic syndrome. Immunofluorescent
staining shows IgM deposits in an expanded mesangium
Mesangial.
What NS
____Associated with chronic hepatitis and low serum complement levels
Membranoproliferative.
____ and ____ are also useful therapeutically. for Membranoproliferative NS
Dipyridamole and aspirin
Proteinuria suggestive of problems in?
This can be from either glomerular or tubular diseases, although glomerular diseases can give greater amounts
Proteinuria is also caused by prolonged standing,
which is known as ______
orthostatic proteinuria.
Nitrites. _________educe nitrate to nitrite, which is a marker of infection
Gram-negative bacteria r
By itself, the isolated finding of bacteria in the urine is of very limited significance. The most important exception is in ______ whom you should screen for bacteria
and treat.
pregnant women,
What kind of cast?
Asstd with Dehydration. These casts develop as an accumulation of the normal amount of tubular protein. They do not necessarily mean disease.
Hyaline
What kind of cast?
Asstd with Glomerulonephritis
Red cell
What kind of cast?
Asstd with Chronic renal failure
Broad, waxy
What kind of cast?
Also called “dirty” or “muddy.” They are associated with acute tubular necrosis and represent accumulated epithelial cells
Granular
What kind of cast?
Asstd with Pyelonephritis, interstitial nephritis
White cell
The most common causes of end stage renal disease (ESRD) that require dialysis are __ and ____
diabetes
and hypertension
The anemia of ESRD is ____ and _____
normochromic and normocytic
Cause of Hypocalcemia/Hyperphosphatemia in ESRD
This is from the loss of 1,25-dihydroxyvitamin D production
IN ESRD
High phosphate levels contribute to low
calcium levels by _____
precipitating out in tissues in combination with the calcium.
Tx of High phosphate levels in ESRD
treated with phosphate binders, such as calcium carbonate or calcium acetate
_____ is a substance that simulates the effect of calcium on the parathyroid. It is used in severe, refractory cases
Cinacalcet
MOA of Cinacalcet
Cinacalcet will tell the parathyroid to shut off
parathyroid hormone production and helps decrease phosphate in this way
In ESRD
_____containing phosphate binders should not be used. It is associated both with CNS accumulation and dementia as well as bone abnormalities.
Aluminum-
This is also known as osteitis fibrosa cystica. Bone abnormalities occur because dead kidneys don’t make 1,25 vitamin D. This leads to a low calcium level
Osteodystrophy
The reason for this is not precisely clear, however, this is the most common cause of death for those on dialysis.
Hypertension and Accelerated Atherosclerosis
This is the second most common cause of death in dialysis patients.
Infection.
MCC of infxn in ERSD
The most common organism is Staphylococcus because of
the constant need to penetrate the skin to place someone on dialysis for 4–6 hours 3–4 times
a week.
Although nephrotic syndrome gives thrombophilia because of the urinary loss of ______ the most common coagulation problem with ESRD is
bleeding
protein C, protein S, and antithrombin,
Reason of inc bleeding in ESRD
This is because of uremia-induced platelet dysfunction
Uremia-induced bleeding is treated with ____which releases subendothelial stores of von Willebrand factor and factor VIII, which increase platelet aggregation and
adherence.
desmopressin,
Duration of Survival
Live related donor _______
Cadaver donor _______
Dialysis alone _____
Diabetics on dialysis ____
95% at 1 year, 72% at 5 years
88% at 1 year, 58% at 5 years
30–40% at 5 years
20% at 5 years
Cause iof hyponatremia from ESRD
This generally occurs from either increased free water retention or urinary sodium loss. About
85–90% of sodium is extracellular
An acute 15–20 point drop in sodium level can result in a ____
seizure or coma
Moderate hyponatremia can be managed with ____
normal saline administration combined with a
loop diuretic such as furosemide
Severe and chronic hyponatremia such as that resulting in seizure or coma should be managed with ____
3% hypertonic saline or the V2 receptor-antagonists conivaptan and tolvaptan
These are conditions in which the total body sodium level is truly normal and the sodium blood level is artificially low. Treatment is directed at etiology of the lab
artifact, not specifically the sodium level
Pseudohyponatremia.
The sodium level is decreased by ____for every 100 mg/dL increase in glucose above normal
1.6 mEq/L
How does hyperglycemia cause Pseudohyponatremia
The high glucose load causes a transcellular shift of
water out of the cell into the vascular space unaccompanied by sodium. This drops the
serum sodium level. Mannitol and sorbitol can do the same
Hypervolemic States (Increased ECF). These are all conditions in which there is a decrease in intravascular volume resulting in an increase in ADH secretion from the posterior pituitary. This is a form of appropriate increased ADH syndrome
- CHF
- Nephrotic syndrome and low albumin states
- Cirrhosis
- Renal insufficiency:
Hypovolemic States (Decreased ECF). For most of these, the hyponatremia develops because_____
of the loss of sodium through body fluids and replacement with free water
Urine Na <20 causes
Dehydration
Vomiting
Diarrhea
Sweating
Urine Na >20
Diuretics ACE inhibitors Renal salt wasting Addison disease Cerebral sodium wasting
Causes of hyponatremia with euvolumic states
- Psychogenic polydipsia
- Hypothyroidism: mechanism unknown
- Diuretics: can be both hypovolemic and euvolemic
- ACE inhibitors: probably through an increase in ADH
- Endurance exercise
- Syndrome of inappropriate secretion of ADH (SIADH)
Meds causing SIADH
- SSRIs
- Tricyclic antidepressants
- Haloperidol
- Cyclophosphamide
- Vincristine
- Carbamazepine
- Thiazide diuretics
If urine osmolality is >100 in the presence of hyponatremia, the person most likely has_____
SIADH
Treatment of SIADH is to _____for mild disease and give _____ for severe disease as was previously described.
restrict fluids
hypertonic saline
For chronic disease in which the underlying cause of the SIADH cannot be corrected, therapy with ______.
These medications inhibit the effect of ADH on the kidney tubule and lead to water diuresis.
conivaptan, tolvaptan, or demeclocycline is used
Conivaptan and tolvaptan are ______-antagonists
V2 receptor
Demeclocycline and lithium treat SIADH by inducing _____
nephrogenic diabetes insipidus.
Presentation of hypernatremia
Insensible losses
GI loss:
Transcellular shift:
Renal
Acute hypernatremia is treated with ______
isotonic fluids intravenously
Watching for a decrease in urine volume after administering_______ distinguishes CDI from NDI.
ADH
Mx of CDI.
- Correct the underlying cause, if possible.
- ______
Vasopressin (ADH). It can be given subcutaneously, intravenously, intramuscularly, or by nasal spray (all routes except oral).
Mechanism of trancellular shift causing hypo K
Increased entry into cells (transcellular shift) can be from alkalosis, increased levels of insulin, beta adrenergic activity, and the replacement of vitamin B12 in B12-deficient patients.
Trauma patients have increased beta adrenergic activity, that may lead to hypokalemia
effect of Mg on K levels
Low magnesium levels. Magnesium decreases urinary loss of potassium. When you are deficient in magnesium, you start to spill potassium into the urine.
Most impt dxtic in hypoK
In emergency cases, the most important diagnostic test is the EKG.
EKG findings for Hypo K
EKG abnormalities include T-wave flattening and U-waves.
____ is an extra wave after the T-wave that is indicative of Purkinje fiber repolarization.
U-wave
Why not to use dextrose containing fluids in K correction
Dextrose will provide the shift of potassium into the cells and will further lower potassium levels.
Mechanisms of transcellular shift causing hyperK
_______—secondary hemolysis, mechanical trauma during venipuncture, platelet count >1,000,000 (106), WBC count >100,000 (105)
_______—secondary cellular buffering (H+ moves into cells, K+ moves out)
–– Pseudohyperkalemia
–– Acidosis
Hyper K from decreased urinary excretion
–– Renal failure ––\_\_\_\_\_\_: ACE inhibitors, type IV RTA, adrenal enzyme deficiency; heparin inhibits production of aldosterone –– \_\_\_\_\_\_\_\_\_ or adrenalectomy –– Potassium-sparing diuretics—\_\_\_\_\_ –– NSAIDs
Hypoaldosteronism
Primary adrenal insufficiency (Addison disease)
amiloride, spironolactone
Tx of HyperK
- ______—membrane stabilization (most emergent treatment in presence of EKG abnormalities). Effect is immediate and short lived.
- _______—alkalosis drives K+ into cells. Do not give in same IV line as calcium. Forms CaCO3 precipitates.
- _______—drives K+ intracellular, takes 30–60 minutes to work
Calcium chloride
Sodium bicarbonate
Glucose and insulin
Tx of hyper K
1
2
3
- Diuretics, beta agonists
- Cation exchange resin (Kayexalate)
- Dialysis
For every ____ increase in the level of serum bicarbonate, there is a______point increase in the
pCO2
1-point
0.7-
Volume contraction of dehydration results in an increased level of _____, which leads to ______
aldosterone
metabolic alkalosis
Increased levels of aldosterone in volume contraction lead to increased levels of ______) excretion.
hydrogen ion (H+
Causes of alkalosis from H loss
- Exogenous steroids
- GI loss (vomiting, nasogastric suction)
- Renal loss (Conn syndrome, Cushing, ACTH overproduction, licorice, Bartter syndrome)
- Decreased chloride intake
- Diuretics
Causes of alkalosis from HCO3 retention
Bicarbonate administration
• Contraction alkalosis
• Milk-alkali syndrome
How to compute anion gap
Anion gap = (Na+) – (HCO3 –) + Cl–)
normal: 8–12
Causes of low anion gap Metabolic Acidosis (MAC)
- Myeloma
- Low albumin level
- Lithium
The anion gap is a gauge of the ______ in the bloodstream
unmeasured anions
The majority of the unmeasured anions are usually ____which has a significant amount of negative charge
albumin,
In addition to albumin, which is normal, the other anionic substances are______
lactate, ketoacids, and the metabolic end products of toxic alcohols
Na+ and cations = ______
HCO3 – and Cl– and anions
Causes of NAGMA
- Diarrhea
- Renal tubular acidosis
- Ureterosigmoidostomy
Causes of HAGMA
LA MUD PIE (Mnemonic)
Lactate (sepsis, ischemia, etc.)
Aspirin
Methanol
Uremia
Diabetic ketoacidosis (DKA)—Beta hydroxybutyric acid (BHB) and acetoacetate, which are
formed from fatty acids, are an alternate fuel source because the cells cannot absorb glucose
because there is a deficiency of insulin
Paraldehyde, Propylene glycol
Isopropyl alcohol, INH
Ethylene glycol (antifreeze, low calcium)
Causes of distal RTA (type 1)
- Usually sporadic
- Also secondary to autoimmune disease (e.g., Sjögren syndrome, SLE)
- Drugs—
- Nephrocalcinosis, sickle cell, chronic infection
- Familial
- Chronic hepatitis
Drugs causing distal RTA
amphotericin, lithium, analgesics, iphosphamide
SSx of distal RTA
- Inability to develop a high H+ concentration in urine. Urine pH is >5.3.
- Secondary hyperaldosteronism and hypokalemia
- Nephrocalcinosis and nephrolithiasis
Acid load test; give ammonium chloride, which should lower urine pH secondary to increased H+ formation. With type I RTA, ________
the urine pH remains elevated. Serum bicarbonate
= 10.
MOA of hypoK in pts with distal RTA
Patients with distal RTA develop hypokalemia because patients lose the ability to secrete
hydrogen ions or H+. Instead of excreting H+, the kidney will excrete K+.
TX of distal RTA
Oral bicarbonate is the treatment because bicarbonate reabsorption in the proximal tubule still works.
Also, potassium replacement; potassium citrate will replace both bicarbonate as well as potassium in distal RTA.
Further, citrate is an effective calcium stone antagonist
Etiology of Proximal RTA
Fanconi syndrome, Wilson disease, amyloidosis, myeloma, acetazolamide, vitamin D deficiency, secondary hyperparathyroidism, chronic hypocalcemia, heavy metals, chronic hepatitis, autoimmune diseases such as SLE and Sjögren syndrome
Etiology of Proximal RTA
Inability to absorb bicarbonate. The initial urine pH is basic (until the body loses enough bicarbonate that it is within the range of absorption of the distal tubule), then
the urine will become acidic (pH <5.4).
Patients with type II get_____ whereas type I get
_______ Both get hypokalemia
bone lesions (osteomalacia and rickets),
kidney stones.
Dx of Prox RTA
Patients are unable to absorb bicarbonate loading (sodium bicarb IV) and have a basic urine in the presence of acidemia.
Normal response to bicarbonate loading
Normal individuals do not excrete bicarbonate in
their urine until serum bicarbonate is >24
Tx of Prox RTA
Give potassium; mild volume depletion will enhance proximal bicarbonate reabsorption (a type of contraction alkalosis).
Thiazide diuretics and very large amounts of bicarbonates
are used.
Hyporeninemic/Hypoaldosteronism (Type IV) causes
• An aldosterone deficiency of any cause or adrenal insensitivity to angiotensin II, which normally stimulates aldosterone release • Diabetes (50%) • Addison disease • Sickle cell disease • Renal insufficiency
SSx of Hyporeninemic/Hypoaldosteronism (Type IV) causes
Presence of high urine sodium with oral salt restriction establishes the diagnosis.
TX of Hyporeninemic/Hypoaldosteronism (Type IV)
Treatment. Administration of fludrocortisone
MOA of fludrocortisone
Fludrocortisone has a high degree of mineralocorticoid
effect and is similar to administering aldosterone.
Etiology of hypercalcuria
Increased absorption
Idiopathic renal hypercalciuria
Resorptive
hypercalcuria from Increased absorption causes
–– Vitamin D intoxication
–– Increased vitamin D with sarcoid and other granulomatous disease
–– Familial
hypercalcuria from inc Resorptive causes
–– Hyperparathyroidism (10–30% of patients present with stones)
–– Multiple myeloma, metastatic disease to bone, hypercalcemia of malignancy
Causes of Hyperoxaluria
- Primary familial
* Enteric
UTI causing stones
Urinary infection with urease-producing organisms such as Proteus, Staphylococcus, Pseudomonas, and Klebsiella give a highly alkaline urine that produces struvite stones
Dx of stones
- __________—high-yield test and most cost-effective
- ________—no contrast needed for stones; contrast is to identify masses, abscesses, and tumors; high-yield test
U/S
Helical (spiral) CT scan
TX of nephrolithias
• Shockwave lithotripsy for stones <2 cm. Unfortunately, the fragments may cause
obstruction themselves.
• Ureteroscopy
• Percutaneous removal (requires more anesthesia and hospital stay)
Adult Polycystic Kidney Disease
Extra-renal manifestations
–– Hepatic cysts (40–60%) –– Colonic diverticula –– Hypertension (50%) –– Intracranial aneurysm (10–20%)—other vascular aneurysms may be seen –– Mitral valve prolapse (25%)
This is due to atherosclerotic disease in elderly persons and fibromuscular dysplasia in young women.
Renal Artery Stenosis
Renal Artery Stenosis SSx
The key feature is an upper abdominal bruit radiating laterally, which is present
in 50–70% of patients
RAS
The best initial screening test is the _____
abdominal U/S.
The______ is a test that measures the uptake of a radioisotope before and after the administration of captopril. A positive test is when there is decreased uptake of the isotope (i.e., decreased GFR) after giving the
captopril
captopril renogram
RAS
The ______ is still the best method of confirming the diagnosis
arteriogram
Best initial Tx of RAS
The best initial treatment is percutaneous transluminal angioplasty. If stenosis recurs, then the procedure should be repeated. If angioplasty fails, surgical resection is
attempted
This is most commonly due to a unilateral adenoma. Adenomas can also be bilateral. The rest of the cases are from bilateral hyperplasia
Primary Hyperaldosteronism (Conn Syndrome
SSx of Conn syndrome
Hypertension in association with hypokalemia found on routine screening tests or
• Symptoms of hypokalemia such as muscular weakness and polyuria and/or polydipsia from a nephrogenic diabetes insipidus
Dx of Conn
Elevated aldosterone levels in urine and blood.
Tx of Conn
Surgical resection in those with an adenoma. Potassium-sparing diuretics such as spironolactone in those with hyperplasia
The key feature is episodic hypertension in association with headaches, sweating, palpitations, and tachycardia. Pallor or flushing may also occur.
Pheochromocytoma
The best initial tests are
urinary vanillylmandelic acid (VMA), metanephines, and
free urinary catecholamines
The key feature is hypertension in association with characteristic cushingoid manifestations such as truncal obesity, buffalo hump, menstrual abnormalities, striae and
impaired healing, etc.
Cushing Disease
Dx of Cushings
Dexamethasone suppression testing and 24-hour urine cortisol are the best initial tests.
