renal

Question 1

what is the effect of dehydration on FF (filtration fraction)

Question 2

decrease circulating BV (diarrhea and vomiting) –> dec renal plasma flow

which will result in the relase of renin –> inc angiotensin II –> efferent glomerular arterioles constriction to maintain the GFR

know that the dec in GFR in hypovolemia is less than the decrease in RPF

so the ratio (FF) GFR/RPF increases

Question 3

Excretion = ?

Answer 3

Excretion = (filtration + secretion) - reabsorption

Question 4

loss of HCO3- in the proximal tubules

diagnosis

Answer 4

type 2 RTA

same mechanism as suppressing the carbonic anhydrase enzyme

cant reabsorb bicarb –> acidosis

Question 5

2 questions on boards

canagliflozin

moa

side effect

Answer 5

sodium glucose co-transport inhibitors (SGLT-2 inhibitors)

in the PCT. –> inc renal excretion of glucose

side effect: glucosuria –> UTI, genital mycotic infections

Question 6

explain how ADH works

know its water soluble (binds to membrane receptors)

vs

aldosterone = lipid soluble (goes into cell)

Answer 6

it stimulates V2 receptors (through cAMP) in the late distal tubules and collecting ducts –> facilitates insertion of water channels (Aquaporin) in the renal collecting ducts –> inc free water reabsorption

know that ADH activates V1 receptors (by IP3 mechanism) –> vasoconstriction –> vascular resistance.

Question 7

a pt with orthostatic hypotension due to blood loss.

what will happen

Answer 7

inc ADH

Question 8

how is lithium nephrotoxic

Answer 8

inhibits the renal actions of vasopressin

(blocks aquaporin function!!!!) thus pt will develop diabetes insipidus

Question 9

on the boards

pt with confusion, stupor, N/V, seizures or coma

pt has hyponatremia.

what paraneoplastic syndrome is causing this

Answer 9

SIADH

from small cell carcinoma

“pt has cerebral edema from retaining water. this is causing the symptoms”

Question 10

hyponatremia

(confusion, stupor, N/V/ seizures or coma)

can be cause by?

Answer 10

SIADH

addisons disease

SSRI or diuretics

CHF, nephrotic syndrome, liver cirrhosis ( will have normal NA, however there is more h2o in body diluting it) thus can give loops.

Question 11

on the boards

elderly pt with dementia and dehydration

(this isthe most common cause of ?)

Answer 11

hypernatremia.

excessive losses of water from the Urinary tract, seen in pts with uncontrolled diabets mellitus also.

Question 12

on the boards

water losses associated with extreme sweating or severe watery diarrhea

can cause

Answer 12

hypernatremia

Question 13

on the boards

pt with ST depression, flattened T waves and U waves on EKG palpitation and Muscle spasm and Weakness.

diagosis

Answer 13

hypo kalemia

Question 14

what are the meds that cause HYPOKALEMIA

know this

Answer 14

ampohtericin B

cisplatin

loops

thiazide

Question 15

pt has disseminated histoplasmosis

and is on amphotericin B

now he has arrythmia, what is the cause

Answer 15

hypokalemia and hypomagnesia from amphotericin.

Question 16

what drugs can cause HYPERKALEMIA

Answer 16

ace inhibitors and ARBS

K sparing

Nsaids (ibuprofen)

cyclosporin and tacroimus

Pentamidine (used in HIV)

Question 17

Q

HIV pt treated for SJS with pentamidine

what electrolyte innbalance do you expect?

Answer 17

hyperkalemia

Question 18

on the boards

HYPERKALEMIA symptoms

Answer 18

on the boards

pt with malaise

palpitations

and muscle weakness

EKG = peaked T waves and Widening of the QRS complex

Question 19

pt is depressed and hasnt gone to his hemodialysis sessions

now he has muscle weakness and palpations

and get an eKG whats the cause?

Answer 19

hyperkalemia

Question 20

Cisplatin

Gentamicin

Amphotericin B

PPi induced

all these cause?

Answer 20

hypomagnesemia

Question 21

hypomagnesemia may cause potassium wasting in the urine –>

Answer 21

hypokalemia

Question 22

magnesium has what effect on PTH

Answer 22

stimulus secretion coupling of PTH

thus hypomag will dec PTH secretion –> hypocalcemia

Question 23

what is the main factor in secondary HTN due to renal artery stenosis

Answer 23

renin

thus avoid ACE inhibitors

Question 24

low na (sensed by macula densa) or low perfusion in the (afferent arterioles)

stimulate the release of renin from the JG cells.

renin will due what?

Answer 24

acitvate angiotensin –> aldosterone system –> vasoconstriction, Na, and water retention

Question 25

pt with BUN =80, Cr = 2. True volume depletion. what kind of acute kidney injury?

Answer 25

**pre renal azotemia** bc **BUN: Cr ratio\> 20** 80/2 = \>20

Question 26

68 yo man with hx of CHF - no leg edema and his creatinine is 1.2 seen in a walk in clinic for back pain and started on ibuprofen two days later he developed leg swelling, sob and his creatinine is 2.8. what is the most likely cause of his symptoms

Answer 26

**blocking progstaglandin effect** on the **afferent arterioles** (prerenal azotemia) normally prostaglandins normally cause vasodilation of the aff arterioles of the glomeruli AKI with inc creatinine is seen in **prostaglandin dependent pt** **e.g. CHF** who started on NSAID

Question 27

why will AKI pt on ace inhibitors have increase in **creatinine and K**

Answer 27

**angiotensin II** keeps the tone of the efferent arteriole. ACE inhibitor will dilate the efferent decreasing glomerular pressure thus less creatinine is filtered out

Question 28

**tumor lysis syndrome** can cause **POST renal AKI** how

Answer 28

metabolites of nucleic acid turnover --\> increase during cell destruction --\> **inc URIC ACID** --\> renal and ureteric stones. - uric acid precipitates in the ACIDIC medium in the DCT and collecting ducts. **prevention hydration** and **alkalinization of urine,**

Question 29

interstitial edema and infiltration with mononuclear cells (lymphoctes and macrophages) and **eosinophils** in urine

Answer 29

seen in **interstitial nephritis**

Question 30

on boards pt started on **antibiotics (B-lactam**) or **allopurinol**, or **cimetidine** classic triad **fever** **rash** **eosinophilia** and **eosinophil in urine**

Question 31

what are the two important drugs (on boards) that cause **post renal azotemia**

Answer 31

**acyclovir** **indinavir**

Question 32

what are the two important drugs (on boards) that cause **post renal azotemia**

Answer 32

**acyclovir** **indinavir**

Question 33

hexagonal kidney stone

Answer 33

**cystine**

Question 34

for the boards the only stone that is radiolucent on xray

Answer 34

**uric acid** (even though first aid say cystine stones)

Question 35

referred pain to the groin and the scrotum may be seen in male pts with ureteric colic

Answer 35

renal calculi (kidney stone)

Question 36

causes of metabolic alkalosis

Answer 36

**vomiting** and **nasogastric suction** --\> HCL loss * dec serum chloride --\> dec urinary chloride **thiazides** and **loops diuretics** --\> renal Na loss (followed by Cl-) * inc HCO3- reabsorption to maintain electric neutrality * volume contraction induced by diurectic --\> inc aldosterone -\> inc H loss **primary hyperaldosteronism**

Question 37

**normal anion Gap metabolic acidosis** **RENAL TUBULAR ACIDOSIS** **DIARRHEA** REMEMBER that the pt will be dehydrated and that will stimulate?

Answer 37

**release of ADH**

Question 38

in **renal tubular acidosis** why are they all **normal anion gap metabolic acidosis**

Answer 38

bc **hypercholermic**

Question 39

boards which diuretic induced normal anoion agap acidosis

Answer 39

**acetazolamide**

Question 40

what kidney tumor metasizes to **lung** where you see **CANNONBALL** lesions

Answer 40

**renal clear cell carcinoma**

Question 41

wilms tumor arises from embryonal renal cells of?

Answer 41

**metanephros**

Question 42

**bleeding time** is prolonged in pts with **uremia** (Chronic kidney disease) why?

Answer 42

due to **platelet dysfunction** not thrombocytopenia

Question 43

what is the most common cause of CKD in the US or they could ask what is the most common cause of hemodialysis in the US

Answer 43

**type 2 DM** followed by persistent HTN

Question 44

in minimal change disease you get (albumin) proteinuria why?

Answer 44

**loss** of the **negative charges** on the **basement membrane** albumin is **negative charged** so it normally doesnt cross. the negatively charaged _glycosaminoglycans_ (such as heparan sulfate)

Question 45

dehydration your RPF \_\_\_ GFR \_\_\_ FF\_\_\_

Answer 45

RPF **DEC DEC** **GFR dec** **FF inc**

Question 46

**membranous nephropathy**

Answer 46

good question!!! what is the most common nephropathy associated with **renal vein thrombosis???**

Question 47

**membranoproliferative GN**

Answer 47

**hepatitis C virus infection**

Question 48

**minimal change disease** (lipoid nephrosis) is associated with **lymphoma** **membranous nephropathy** is associated with?

Answer 48

**solid tumors**

Question 49

EM: **spike and dome**

Answer 49

**membranous nephropathy**

Question 50

in minimal change disease how does hodgkins lymphoma effect the glomerulus

Answer 50

the lymphokines from the T lymphocytes cause **fusion of the podocytes**

Question 51

Boards (presentations) 1. **african american male, drug abuser, could be homeless** **obese, NOT diabetic** **2. heavy proteinuria in an obese caucasian individual** **3.chronic vesico-ureteric reflux** EM: **no immune complex deposition - effacement of foot processes**

Answer 51

**FSGN** **(focal segmental sclerosis)**

Question 52

on boards tx of minimal change disease **A. prednisone** **B. prednisone** and **cyclophosphamide**

Answer 52

**prednisone**

Question 53

Q on boards what is the most common **SECONDARY** cause of nephrotic syndrome in **adults**

Answer 53

**diabetic nephropathy**

Question 54

trick question diabetic pt, his blood pressure in your clinic is always 110/70. however, on UA he has **microalbuminurea.** what is your next best step in tx?

Answer 54

**start ACEI** or Arbs even if **normotensive**

Question 55

**diabetic nephropathy** can induce what type of RTA?

Answer 55

type **4 RTA** with **hyperkalemia**

Question 56

pathogenesis know that **glomerular hyperfiltration** is caused by dec ristance in both the afferent and efferent arterioles (aff\> eff) -diffuse BM thickening and mesangial cell overproduction -\> **microalbuminuria** (the **earliest clinical sign)** persistent**HYPERGLYCEMIA** is an important factor in pathogenesis of microalbuminuria

Answer 56

**diabetic nephropathy**

Question 57

what is the **earlier clinical sign** of **diabetic nephropathy**

Answer 57

**microalbuminuria**

Question 58

Q **HIV** associated nephropathy what is the pathology

Answer 58

collapsing focal glomerulosclerosis with **tubular microcyst formation** A focal segmental variant

Question 59

Question!!!! treament of **HIV -associated nephropathy**

Answer 59

**ACE -inhibitor**

Question 60

glomerular pathology in **eclampsia**

Answer 60

**Endothelial dysfunction** **_glomerular endotheliosis_** (diffuse endothelial swelling + fibrinogen deposition on the endothelial side of the capillaries) --\> proteinuria (**endothelial proliferation)** **this is the cause of the proteinuria in eclampsia pt**

Question 61

pt with elampsia develops confusion, has cerebral edema what is the cause of this

Answer 61

**not HTN** but do to damage **endothelial cells** in the cerebral vessels.