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what are the major causes of an

anion gap

MUDPILES

Methanol ( formic acid)

Uremia

Diabetic ketoacidosis

Paraldehyde/ phenformin

Iron tablets (INH)

Lactic acidosis

Ethylene glycol (oxalic acid)

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calculation for Filtration fractionFF = GFR/RPF

(rPf, not rbf)

patient being treated for acute leukemia develops oliguria.

renal biobsy reveals multiple uric acid crystals obstructing

the renal tubular lumen. the principle site of uric acid

precipitation would be where?

-tumor lysis syndrome

-large number of tumor cells are destroyed during chemo, and intracellular

ions including uric acid (a metabolite of tumor nucelic acid) are r eleased and

filtered by the kidneys. Uric acid precipates in acidic pHs, and the lowest pH

along hte nephron is distal tubules/collecting duct**prevention: urine alkanization and hydration

what are the two major electrolyte

disturbances seen with amphotericn B-K+ and Mg2+ (hypo)

lymphocytic infiltrate in renal

parehcnyma after renal transplant

T cell mediated allograft rejection

(rejection can also be antibody mediated, but you wouldn't see the

infiltrates (only antibodies would be present)

what do you use to treat T cell mediated

acute organ rejection (kidney, heart and

liver)

OKT3 (anti-CD3)

*inhibits T-cells

hypoxia-induced lactic acidosis is caused

by a low activity of what enzyme

pyruvate dehydrongenase (converting pyruvate into acetyl CoA for

the TCA cycle)

*note: lactate dehydrongenase converts pyruvate into lactic acid

(anerobic respiration)

**note: pyruvate carboxylase converts pyruvate into oxaloacetate

how do loop diuretics work?they inhibit Na -K-2Cl symporters in the ascending limb of the loop of henle and effectively blockNa and Cl transport, resulting in increased Na, Cl and fluid excretion**Loops also stimulate prostaglandin release, which increases renal blood flow, leading toincreased GFR (and enhancing drug delivery)*thus, using NSAIDs at the same time can r esult in a decreased diuretic response

which class of diuretics is the most

potent?

loop diuretics

-used for treating edema

what are the common side effects of

loop diuretics?

hypocalcemia, hypokalemia, hypomagnesemia and otoxoicity

-usually occurs with rapid IV administration, or when loops are

used in combo with other ototoxic agents like aminoglycosides,

salicylates and cisplatin

-hearing impairment is usually reversible

what happens to the GFR, RPF and

FF in sever hypovolemia?

-large decrease in RPF

-moderate decrease in GFR (efferent arteriole constricts)

-FF increases (because the RPF drops much more than

the GFR)

YKS RENAL

RENAL2

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what is the preferred method for

diagnosin diabetic nephropahty

measuring albumin in the urine

-diabetic nephropathy is the leading cause of

ESRD in the US

a child with selective protienuria (albumin

only) due to loss of negatively charged

components of the basement membrane

minimal change nephrotic syndrome

what is the primary site of K+ excretion

(concentrating the urine with potassium)the collecting duct

what happens to the the concentrations of PAH,

creatinine, inulin and urea as fluid runs along the

proximal tubule (tubular fluid/plasma ultrafiltrate graph)their concentration increases

what happens to the concentration of bicarb, glucose and

amino acids as fluid moves along the proximal tubule

(tubular fluid/ultrafiltrate graph)decreases

what effect does vasopressin (ADH)

have on excretionof urea

urea reabsorption into the inner medullary

INTERSTITIUM increases, thus fractional

excretion of urea decreases

what is the most common cause of

intrinsic renal failure in hospitalized

patients

ATN

what parts are the first to suffer when

blood flow (oxygen delivery) to the kidneys

is low

the proximal tubules and the ascending limb

-there location in the medulla already makes them have

low blood supply

-they use ATP to transport ions, so they must have O2

relative risk tableexposure in the rows

outcomes in the columns

what electrolyte problems will you see in a

patient with renal damage from

amphotericin B

hypokalemia, hypomagnesemia due to

distal tubular membrane permeability

YKS RENAL

RENAL3

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Kimmelsteil Wilson nodules

diabetic nephropathy

-diabetic nephropathy starts with glomerular hyperfiltration and

leads to an increase in mesangial matrix and thickening of the

basement membrane

-affects the glomeruli and arterioles

which classes of drugs prevent the

progression of diabetic nephropathy

ACE inhibitors and ARBs

which antipsychotic drug can cause a

drug-induced diabetes insipiduslithium

what is calcineurin?-protein phosphotase in T cells

-allows for the production of IL-2, which stimulates the

growth and differentiation of T cells

which two drugs used in kidney

translpants inhibit calcineurinCyclosporine and Tacrolimus

what is the most important prognostic

factor in post-strept glomerulonephritis

age

-kids have a better prognosis than adults

what is the likely etiology of visual

impairment in an HIV infected patient

it's secondary to CMV-induced retinitis,

which is treated with ganciclovir, cidofovir

and foscarnet

Foscarnet

antiviral med used to treat CMV retinitis

-analog of pyrophosphate that can chelate Ca++ and

promote nephrotoxic renal magnesium wasting. Can

result in hypocalcemia and hypomagnesemia

What effect does acyclovir have on the

kidneys?

acyclovir causes crystilline nephropathy i

adequate hydration is not also provided

what often causes formation of

calcium oxalate crystals

ethylene glycol (antifreeze)

-antifreeze also causes an anion gap

metiabolic acidosis, increased osmolar gap

YKS RENAL

RENAL4

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where is glucose filtered and where is

it reabsorbed?

glucose is normally filtered at the

glomerulous and completely reabsorbed by

the proximal tubule

if most of the glucose filtered is

reabsorbed in hte proximal tubules, why

does glycosuria occur?

reabsorption of glucose occurs via Na/glucose co-

transporters--> because this process is carrier mediated, i

can become oversaturated

*notes: the renal tubules DO NOT secrete glucose

which substances are not reabsorbed

or secreted in the tubulesInulin and Mannitol

which substances have a net tubular

reabsorption (the amount actually excreted

is far less than the amount initially filtered)glucose, sodium, urea

which substances are filtered,

secreted and not reabsorbed

PAH(creatinine is filtered and not reabsorbed, but only a l ittle is s ecreted)**note: PAH is secreted via carrier mediated transport; simila r to g lucose, but glucose is beingreabsorbed by NA/glucose co-transporters in the proximal tubules, whereas PAH is beingSECRETED by carri ers in the tubules**the secretion of PAH can become saturated (b/c it uses ca rriers), but the filtra tion cannot besaturated

spironolactone

K+ sparring aldosterone antagonist diuretic used in treating class

II and IV heart failure patients

*it's structurally similar to steroids, so it can cause gynecomastia,

decreased libido and impotenece

**Eplerenone is a newer drug with less endocrine effects.

a patient with a metabolic acidosis

with a normal pCO2

this patient has a superimposed respiratory acidosis (respiratory failure)

*metabolic acidosis causes a drop in the HCO3-, adn your body will try and

even things about by blowing off CO2 in an attempt to get rid of some acid. If

the pCO2 remains normal, it means your body isn't able to blow off CO2

a tear in the gastric mucosa near the

gastroesophageal junction

Mallory-Weiss tear

-caused by excessive vomiting

-recurrent vomiting can cause a metabolic acidosis (you're losing a

lot of the acid in your stomach)

why is spironolactone a part of the

standard therapy for class III and IV heart

failure patients

-mild diuretic effects

-inhibition of the neurohormonal eff ects of aldosterone leading to decreased

ventricular r emodeling and cardiac fibrosis

*in heart failure, the RAAS is act ivated---> leads to elevated aldosterone-->

aldosterone is known to cause ventricular remodeling leading to cardiac

fibrosis

c-ANCA

-cytoplasmic antineutrophil c ytoplasmic ant ibody

-Wegener's granulomatosis (RPGN/pauci immune)

includes:

-nephritis

-lung involvement

-crescent on light microscopy (irreversible sclerosis)

**there are no immune d eposits on immunofluorescence, despite the f act th at it's type III hyp ersens... just

c-ANCA

YKS RENAL

RENAL5

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effacement of foot processesminimal change disease (seen on

EM)

where in the nephron do most clear cell

renal carcinomas originate from

from the epithelial cells of the proximal

tubule

(clear cells are filled with fat and glycogen)

what do the antibodies in Goodpasture

syndrome react with (be specific)

alpha3-chain of collagen type IV,

found in the basement membrane

linear deposits of IgG and C3 along hte

basement membrane on

immuofluorescence

Goodpasture syndrome

what are some causes of secondary

hyperaldosteronism

-renovascular hypertension (usually associated with fibromuscular

dysplasia or atherosclerosis)

-diuretic use

-malignant hypertension

-renin-secreting tumors

painless hematuria 2-3 dyas after an

upper repiratory tract infection

IgA nephropathy (Berger disease)

-IgA deposits in the mesangium of glomeruli

on IF microscopy only!)

IgA nephropathy accompanied by extrarenal symptoms

(abdominal pain, joints (arthralgia and arthritis)

purpuric skin lesions

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what is the most serious concern during

the recovery phase (polyuric phase) of

ATN

hypoKalemia

affect of salicylate intoxication of pH-first causes and acute respiratory alkalosis

-with high doses, a superimposed metabolic acidosis will

occur (the acidosis will predominate)

cystic dilations of the MEDULLARY

collecting ducts

medullary sponge kidney

-the cysts don't involve the cortex (like in ADPKD)

-kidney stones are the only problem that could arise

what is one of the more sever

toxicities of Mannitolpulmonary edema

what effect does ureteral

constriction/obstruction have on GFR and

FF

acutely decreases the GFR and

glomerular filtration fraction

what is the equation for the net excretion

of a substance that is filtered and

reabsorbed

total filtration rate - total tubular reabsorption rate

total filtration rate = GFR x Plasma

diffuse thickness WITHOUT

hypercellularity spike and dome

appearance on EM

membranous glomerulonephropathy

-can occur secondary to tumors, infections

and certain medicatons

What labs do you expect to see with

post-streptglomerulonephritis?

-elevated anti-streptolysin O titers

-elevated anti-DNAse B titers

-decreased C3

-cryoglobulins

male patient with nephrotic syndrome

and a left-sided variocele (fluid in testis)

renal vein thrombosis due to decrease in antithrombin III

*left testicular vein drains in to the left renal artery, then into the

IVC (right testicular artery has a straight shot to the IVC); a

decrease in antithrombin III can cause a renal vein thrombosis,

which will back up drainage of the left testis, causing a variocele

female presenting with flank pain that

radiates to the groin after a hysterectomy

hydronephrosis due to damage of the ureter during the

hysterectomy

*the ureters lie just posterior to the uterine arteries, which

are ligated during this procedure

YKS RENAL

RENAL7