Renal Pathology

Front 1

In bilateral renal agenesis, ultrasound shows ____________. Explain why this happens.

Back 1

oligohydraminos. THe fetus normally eats amniotic fluid, and then urinates it out. When a fetus doesn't have the ability to filter blood and excrete waste, it retains this fluid and waste. The amniotic fluid will be less because the fetus doesn't "recycle" it.

Front 2

Fetuses with bilateral agenesis typically have distinctive features called, _______ ______. Describe this.

Bilateral agenesis is also associated with hypoplasia of which critical organ?

Back 2

Potter facies. flattened nose, low-set ears, and recessed chin, talipes equinovarus / clubfoot (talus (ankle) + pes (foot) + equino (heel) + varus (turned upward))

Pulmonary hypoplasia (so answer = lungs). Swallowed amniotic fluid also helps with lung development.

Front 3

What is the cause of death in infants with bilateral renal agenesis

Back 3

Respiratory failure. Although they can't urinate, the lungs failing will be the more acute issue causing death within a few hours.

Front 4

In unilateral renal agenesis, what happens to the single kidney? Do patients have normal renal function?

Back 4

The remaining kidney undergoes compensatory hypertrophy. They do have adequate renal function but they may develop progressive glomerular sclerosis.

Front 5

What is wrong with the kidney if it is hypoplastic? Causes?

Back 5

kidney that failed to develop a normal weight. Decreased # of calyces and lobes.

Fetal alcohol syndrome, renal artery stenosis, in utero cocaine exposure

Front 6

WHat is horseshoe kidnney and are patients with it predisposed to anything?

Back 6

Common congenital anomaly that is found in 1 in 750 autopsies. Kidneys show fusion, usually at the lower pole; affected individuals have normal renal function but may be predisposed to renal calculi.

Front 7

What is the most common abnormal location of an ectopic kidney? Do these kidneys have normal function?

Back 7

pelvic. Yes. but tortuosity of ureters may predispose to pyelonephritis or just UTIs in general.

Front 8

What is a good way to find the central portion of the horseshoe kidney? Why is it found there?

Back 8

Just inferior to the inferior mesenteric artery. Its embryologic ascent is arrested by the artery's presence

Front 9

How does autosomal recessive polycystic kidney disease present?

Back 9

Rare disease that presents with progressive and often fatal renal failure.

Front 10

Explain the morphology of the kidneys and liver in AR (or childhood) polycystic kidney disease.

Back 10

Kidneys- bilaterlaly enlarged with multiple small cysts in the cortex and medulla. Cysts occur in the collecting ducts of the nephron and are consequently oriented in a radial fashion with their long axis at right angles to the renal capsule.

Liver- patients may also have multiple hepatic cysts and congenital hepatic fibrosis.

Front 11

What is the epidemiology of adult polycystic kidney disease?

Back 11

Autosomal dominant, affects 1 in 1000 people.

Front 12

Which gene is affected in adult polycystic kidney disease?

Back 12

PDK1 gene on chromosome 16. Produces a transmembrane protein called polycystin 1. other mutations involve PKD2 and PKD3 genes.

Front 13

Describe the clinical presentation of adult PKD. (age of presentation, clinical syndromes, diagnostic procedures, prognosis)

Back 13

Asymptomatic with normal renal function until Middle age, and then present with renal insufficiency, hematuria, and hypertension or with abdominal masses and flank pain. the diagnosis is established with ultrasound and CT scans. Most patients develop end-stage renal failure by their seventh decade.

Front 14

What is the chapman's reflex for the kidneys?

Back 14

1 inch superior and 1 inch lateral to the umbilicus and/or the spinous process of L1.

Front 15

In patients with symptomatic adult PKD, gross and microscopic pathologic examination will show...?

Back 15

kidneys have massive bilateral enlargement with large bulging cysts filled with serous, turbid, or hemorrhagic fluid.

Microscopic examination shows functioning nephrons present between the cysts; the cysts arise from the tubular structures of the nephron. reduction of the number of glomeruli, some of which may be hyalinized.

Renal arteriolar thickening is a prominent finding in adults

Front 16

Extrarenal manifestations of adult pkd?

Back 16

Liver cysts, berry aneurisms of the circle of willis, MVP, and colonic diverticula

Front 17

What is the proportion of nephrons involved in PKD? (Why can patients be asymptomatic for so many years?)

Back 17

Less than 10%! but they gradually expand and compress the rest of the kidney, interfering with its function. This is the reason why kidney function can remain normal for many years.

Front 18

What is the most common renal cystic disease in kids?

Back 18

Renal dysplasia.

Front 19

What is the pathology of renal dysplasia involve?

Back 19

causes enlarged renal mass with cartilage and immature collecting ducts. May progress to renal failure. Usually unilateral.

Front 20

Define dysplasia.

Back 20

Abnormal growth of cells

Front 21

Medullary sponge kidney disease causes what?

Back 21

multiple cysts of collecting ducts with a "swiss cheese" appearance. It may predispose to recurrent urinary tract infections, hematuria, and renal stones.

Front 22

Who is at risk for developing acquired PKD?

Back 22

renal dialysis patients. Associated with a small risk of developing renal cell carcinoma.

Front 23

What are retention cysts?

Back 23

Can be common in adults. cysts of the kidney that can compress the ureter causing hydronephrosis or in the parenchyma, causing local damage. It rarely decreases renal function, however. Sometimes associated with hematuria

Front 24

List the clinical findings in Nephritic Syndrome.

Back 24

Hematuria (RBC casts)

HTN

Azotemia

Oliguria

Proteinuria (<3.5g/day)

Front 25

List the clinical findings in Nephrotic Syndrome

Back 25

Severe proteinuria (>3.5g/day)

Hypoalbuminemia (<3g/dL)

Generalized edema (due to decreased oncotic pressure)

Hyperlipidemia (think that the liver needs to bulk up the blood due to loss of protein)

Lipiduria

Hypercoagulable state because of a loss of antithrombin III (preferential loss) - lost an anticoagulant protein. Breaks up thrombin and destroys coagulation factors...

Front 26

What is the most common cause of nephrotic syndrome in kids? This is usually ________pathic but may be associated with _________ _________ (type of cancer).

Back 26

Minimal change disease

usually idiopathic

Hodgkins Lymphoma - caused by production of cytokines... they flatten the foot processes... resulting in MCD

Front 27

Which layer of the filtration system do you lose in MCD?

Back 27

foot processes (effacement of the foot processes-- flattening)

Front 28

Key findings in MCD?

Back 28

normal glomeruli on H&E stain, lipid may be seen in proximal tubule cells

Effacement of foot processes on EM

No immune complex deposits; negative IF

Front 29

Which type of proteinuria do you have in MCD?

Back 29

selective (loss of albumin but not immunoglobulin.)

Front 30

What is the treatment for MCD? How does it work?

Back 30

Steroids. Have an excellent response! Damage is mediated by cytokines from T cells so steroids help.

Front 31

what is the functional unit of the glomerulus? How are they held together?

Back 31

lobules; mesangium (mesangial cells)

Front 32

How can you tell if the foot processes are effaced on EM?

Back 32

look for landmarks. RBCs on capillary side, endothelial cells, BM, and foot processes.. the last 2 should be right next to each other.

Front 33

What is the most common cause of nephrotic syndrome in Hispanics and African Americans?

What are the associated causes?

Back 33

FSGS (focal segmental glomerulosclerosis)

usually idiopathic (as are most nephrotic diseases) but can be associated with HIV, Heroin use, and sickle cell disease

Front 34

HIstological features of FSGS?

Back 34

focal and segmental sclerosis on H&E (only involves one segment of the glomerulus; only involves some of the glomeruli) -- pink sclerosis

Effacement of foot processes on EM

No immune complex deposits; negative IF

Front 35

If MCD did not respond to steroids, to which disease might it progress?

Back 35

Focal Segmental Glomerular Sclerosis (also see effacement of foot processes)

Front 36

How does FSGS respond to steroids? What happens when it progresses?

Back 36

Poor; progresses to renal failure.

Front 37

What is the most common cause of nephrotic syndrome in Caucasian adults?

Associated causes?

Back 37

Membranous nephropathy

Usually idiopathic; may be associated with hep B, hep C, solid tumors, SLE (most common cause of death is renal failure from diffuse proliferative glomerulonephritis; however, they can also present with nephrotic syndrome), or drugs (e.g. NSAIDs and penicillamine)

Front 38

Histologic features of membranous nephropathy?

Back 38

thick glomerular basement membrane on H&E

Due to immune complex deposition (granular IF) - deposits right beneath the podocytes, the podocyte will respond by trying to lay down more Basement membrane. This generates a dome over each deposit... inbetween the domes, you get spike deposits.

(any disease that has the word membranous in it, you get thickening of the membrane due to immune complex deposition)

Subepithelial deposits with 'spike and dome' appearance on EM

Front 39

Membranoproliferative glomerulonephritis shows _____ capillary membranes on H&E, often with "____-_____" appearance.

Due to _______ _______ _______.

Explain what is proliferating and why you see the major feature.

Back 39

thick; tram-track; immune complex deposition (underneath the epithelium or in the basement membrane.

Mesangium is proliferating, which creates two lines, cutting through the middle of the deposit.

Front 40

Describe the differences/similarities between the two types of Membranoproliferative glomerulonephritis.

Back 40

Type I: deposits underneath the endothelial cell. Associated with HBV and HCV. More often associated with the formation of tram-tracks.

Type II: deposition of immune complexes within the BM. These patients have an antibody in their blood called C3 nephritic factor, which stablizes C3 convertase. This leads to the overactivation of complement -> inflammation -> which can drive this process forward. You'll get a decreased C3, and overactivation of complement...

Front 41

Membranoproliferative glomerulonephritis can create either _______ ________ OR ________ _______

Back 41

Nephritic syndrome or nephrotic syndrome

Front 42

In DM, what happens in the arterioles of the kidney? is it preferential to a specific arteriole?

Back 42

high serum glucose leads to NEG of vascular BM resulting in hyaline arateriolosclerosis

Efferent arteriole is more affected than afferent arteriole, leading to high Glomerular filtration pressure -- begins as microalbuminuria and results in sclerosis of mesangium of the glomerulus due to back pressure and hyperfiltration (Kimmelstiel Wilson nodules)... this will progress to nephrotic syndrome.

Front 43

How would you slow the progression of hyperfiltration injury?

Back 43

ACE inhibitors - block angiotensin II

Front 44

What is the first change seen in the kidney in a patient with DM?

Back 44

NEG of arterioles... especially the efferent arteriole

Front 45

In patients with systemic amyloidosis, which organ is the most commonly involved organ?

Back 45

kidney

Front 46

Amyloid deposits in _________ result in nephrotic syndrome. How is it characterized on IF?

Back 46

mesangium; apple-green birefringence under polarized light

Front 47

Hallmarks of nephritic syndrome? (labs, signs...)

Back 47

limited proteinuria (<3.5g/day)

Oliguria and azotemia (increased nitrogenous waste in blood)

Salt retention with periorbital edema (loose connective tissue around eyes) and hypertension

RBC casts and dysmorphic RBCs in urine (key signs of glomerular bleeding)

Front 48

biopsy of nephritic syndrome kidney would show what? How does this damage occur?

Back 48

hypercellular inflamed glomeruli

Immune complex deposition activates complement

C5a attracts neutrophils, which mediate damage

Front 49

WHat is the prototypic nephritic syndrome?

Back 49

Post Strep Glomerulonephritis (PSGN)

Nephritic syndrome that arises after group A beta-hemolytic strep infection of skin (impetigo) or pharynx

Front 50

Do all strains of strep A produce PSGN?

Back 50

no, mostly just occurs with nephritogenic strains. These are defined as the strains that carry M protein virulence factor. ***May occur after infection with non-strep organisms as well. But prototypically its 2-3 weeks after a strep a beta-hem. infection

Front 51

How do patients with PSGN present?

Back 51

2-3 weeks after a strep a beta-hem. infection

Hematuria (cola-colored urine)

Oliguria

HTN

Periorbital edema

Usually seen in children, but may occur in adults

Front 52

What would you see if you biopsied a patient with PSGN?

Back 52

hypercellular, inflamed glomeruli on H&E

Mediated by immune complex deposition (granular IF)

Subepithelial "humps" on EM

-start as subendothelial and then work their way up... eventually they just disappear

Front 53

Treatment for PSGN?

Back 53

Supportive.

Children rarely progress to renal failure. Some adults develop Rapidly progressive glomerulonephritis.

Front 54

What is RPGN?

Back 54

nephritic syndrome that rapidly progresses to renal failure in weeks to months

Front 55

Biopsy of RPGN is characterized by what?

Back 55

crescents in bowman space (H&E)

Front 56

What are the crescents composed of?

Back 56

fibrin and macrophages (NOT COLLAGEN).. its inflammatory debris

Front 57

What would linear flourescence mean?

Back 57

linear flourescence - anti-basement membrane antibody - Goodpasture syndrome - Ab against collagen in glomerular and alveolar BM. Presents as hematuria and hemoptysis, classically in young, adult males.

Front 58

What would granular IF indicate?

Back 58

PSGN (most common) or diffuse proliferative glomerulonephritis

Diffuse proliferative GN is due to diffuse Antigen-Antibody complex deposition, usually subendothelial; most common type of renal disease in SLE

Front 59

What is the cause of nephrotic syndrome in lupus patients?

Back 59

membranous nephropathy

Front 60

If you have a negative IF, by what diseases might it be caused?

Back 60

Wegener granulomatosis, microscopic polyangiitis, and Churg-Strauss syndrome.

Front 61

Wegener granulomatosis is associated with which positive lab result? How does this compare to Churg-Strauss?

Back 61

Positive C ANCA (cytoplasmic antineutrophil cytoplasmic antibody)

Churg-Strauss are associated with p-ANCA (perinuclear ANCA)

Front 62

You can also see a p - ANCA in which other disease?

Back 62

microscopic polyangiitis

Front 63

How do you distinguish Churg-Strauss from microscopic polyangiitis?

Back 63

Granulomatous inflammation, eosinophilia, and asthma distinguish Churg-Strauss from microscopic polyangiitis

Front 64

What is the most common cause of nephropathy worldwide?

Back 64

IgA nephropathy

Front 65

IgA nephropathy is defined as IgA complex deposition in _______ of _______.

Back 65

mesangium of glomeruli

Front 66

If you are given an IF with IgA labeled biopsy, it will always indicate which disease?

Back 66

IgA nephropathy... nothing else we've covered has IgA complex deposition

Front 67

IgA nephropathy presents during ________.

Clinical features (labs)

Prognosis?

Back 67

childhood.

Episodic gross or microscopic hematuria with RBC casts, usually following mucosal infections

(episodic because as mucosal infection regresses, you have less deposition of complexes)

May slowly progress to renal failure

Front 68

Name that syndrome: Inherited defect in type IV collagen; most commonly _-______.

Back 68

ALport syndrome; x-linked

Front 69

Alport syndrome results in _______ and _______ of glomerular BM. what are the 3 key findings along with Family history that indicate its alport syndrome?

Back 69

thinning; splitting

isolated hematuria, sensory hearing loss, and ocular disturbances

Front 70

Infections of which structures constitute UTIs?

Back 70

urethra, bladder, or kidney.

Front 71

UTIs most commonly arise due to __________ infection; increased incidence in males or females?

Back 71

ascending; females

Front 72

What are the risk factors for UTIs

Back 72

Sexual intercourse, urinary stasis, and catheters

Front 73

What presents as dysuria, urinary frequency, urgency, and suprapubic pain without systemic signs?

Back 73

Cystitis - infection of the bladder

Front 74

What are the lab findings of cystitis?

Back 74

UA: cloudy urine with > 10 WBCs/hpf

Dipstick: positive leukocyte esterase (due to pyuria) and nitrites (bacteria take nitrates present in the urine and form nitrites)

Gold standard: Culture: > 100,000 colony-forming units

Front 75

Which microbes commonly cause UTIs? most common?

Back 75

E coli most common (80%) -even among sexually active females

Staph. saprophyticus - increased incidence in young, sexually active women

Klebsiella pneumoniae (nosocomial)

Proteus mirabilis - will cause an alkaline urine with an ammonia scent

Enterococcus faecalis

Front 76

If you have sterile pyuria, how does your differential change?

Back 76

Pyuria with negative urine culture - suggests urethritis due to chlamydia trachomatis or Neisseria gonorrhoeae

Front 77

Define pyelonephritis and explain what increases the risk for developing it.

Back 77

infection of the kidney. Usually due to ascending infection; increased risk with vesicoureteral reflux

Front 78

How does pyelonephritis present?

Back 78

fever, flank pain (inflammation results in sensitization of the capsule of the kidney), wbc casts, and leukocytosis in addition to symptoms of cystitis

Front 79

What ar ethe most common pathogens for pyelonephritis?

Back 79

E coli (90%)

Klebsiella species

Enterococcus faecalis

Front 80

Describe chronic pyelonephritis and when you classically see it/

Back 80

interstitial fibrosis and atrophy of tubules due to multiple bouts of acute pyelonephritis. Due to vesicoureteral reflux (children) or obstruction

Front 81

What type of anatomic malformation would increase the risk of pyelonephritis?

Back 81

the angle at which the ureters enter the bladder...

Front 82

Gross description of what happens in chronic pyelo?

Back 82

Cortical scarring with blunted calyces.

Scarring at upper and lower poles is characteristic of vesicoureteral reflux

Front 83

In chronic pyelo, the kidney starts to look like which other organ?

Back 83

thyroid. Atrophic tubules contain eosinophilic proteinaceous material reminiscent of thyroid follicles (colloid present within thyroid follicles).

Waxy casts may be seen in urine

Front 84

Nephrolithiasis is what?

Back 84

precipitation of a urinary solute as a stone

Front 85

What are the risk factors for nephrolithiasis?

Back 85

High concentration of solute in urinary filtrate and low urine volume.

Front 86

How does nephrolithiasis present?

Back 86

colicky pain with hematuria and unilateral flank tenderness. Stone is usually passed within a few hours but if its not, surgery is required.

Front 87

What is the most common kidney stone?

Back 87

calcium oxalate and/ or calcium phosphate. Most common cause is idiopathic hypercalciuria; calcium level in the blood is normal but elevated calcium in the urine.

Hypercalcemia and its related causes must be excluded. Also seen with crohn disease (small bowel damage increases absorption of calcium oxalate). Treatmetn is HCTZ (calcium-sparing diuretic)

Front 88

What is the 2nd most common type of kidney stone?

Back 88

ammonium magnesium phosphate. Most common cause is with urease-positive organisms (proteus vulgaris or Klebsiella); alkaline urine leads to formation of stone.

Classically results in Staghorn calculi in renal calyces which act as a nidus for urinary tract infections. Tx involves surgical removal of stone (due to size) and eradication of pathogen (to prevent recurrence).

Front 89

Which substance makes up the 3rd most common kidneystone?

Back 89

uric acid. (5%). it is radioleucent (others are radiopaque).

Risk factors include hot, arid climates, low urine volume, and acidic pH. Most common stone seen in patients with gout; hyperuricemia (e.g., in leukemia or myeloproliferative disorders) increases risk.

Treatment involves hydration and alkalinization of urine (potassium bicarbonate); allopurinol is also administered in patients with gout.

Front 90

What is the most rare cause of nephrolithiasis but most commonly seen in kids?

Back 90

Cysteine. Associated with cystinuria (a genetic defect of tubules that results in decreased reabsorption of cysteine).

May form staghorn calculi; treatment involves hydration and alkalinization of urine.