Renal Pathology Flashcards
1
Q
What do casts in the urine indicate?
A
Presence of casts indicates that hematuria/pyuria is of glomerular or renal tubular origin
2
Q
What are two conditions that cause hematuria without casts in the urine?
A
Bladder Cancer and Kidney Stones
3
Q
What condition causes pyuria without casts in the urine?
A
Acute cystitis
4
Q
What are three conditions that cause RBC casts in the urine?
A
- Glomerulonephritis
- Malignant Hypertension
- Ischemia
5
Q
What are three conditions that cause WBC casts in the urine?
A
- Tubulointerstitial inflammation
- Acute pyelonephritis
- Transplant rejection
6
Q
What causes fatty casts (oval fat bodies) in the urine?
A
Nephrotic Syndrome
7
Q
What causes granular (muddy brown) casts in the urine?
A
Acute Tubular Necrosis (ATN)
8
Q
What causes waxy casts in the urine?
A
End-stage renal disease/chronic renal failure
9
Q
What causes hyaline casts in the urine?
A
Non-specific finding, can be a normal finding, often seen in concentrated urine samples
10
Q
What does it mean when a glomerular disorder is focal and what is an example?
A
Focal:
11
Q
What does it mean when a glomerular disorder is diffuse and what is an example?
A
Diffuse: >50% of glomeruli are involved
Ex: Diffuse proliferative glomerulonephritis
12
Q
What characterizes a proliferative glomerular disorder and what is an example?
A
Hypercellular glomeruli
Ex. Membranoproliferative glomerulonephritis
13
Q
What characterizes a membranous glomerular disorder and what is an example?
A
Thickening of glomerular basement membrane (GBM)
Ex. Membranous nephropathy
14
Q
What characterizes a primary glomerular disease and what is an example?
A
A primary disease of the kidney specifically impacting glomeruli
Ex. Minimal change disease
15
Q
What characterizes a secondary glomerular disease and what is an example?
A
A systemic disease or disease of another organ system that also impacts the glomeruli
Ex. SLE, diabetic nephropathy
16
Q
What is the cause/site of damage in Nephritic syndrome and what are the clinical manifestations?
A
Due to glomerular basement membrane (GBM) disruption leading to:
- Hypertension (due to salt retention)
- Increased BUN and creatinine
- Azotemia (high levels of nitrogen containing compounds)
- Oliguria (production of abnormally small amount of urine)
- Hematuria / RBC casts in urine
- Proteinuria often in the subnephrotic range (
17
Q
What are five examples of diseases that are considered Nephritic Syndrome?
A
- Acute post streptococcal glomerulonephritis
- Rapidly progressive glomerulonephritis
- IgA nephropathy (Berger Disease)
- Alport Syndrome
- Membranoproliferative glomerulonephritis
18
Q
What is the cause/site of damage in Nephrotic syndrome and what are the clinical manifestations?
A
Due to podocyte foot process damage disrupting the filtration charge barrier
- Massive proteinuria (>3.5 g/day)
- Hypoalbuminemia
- Hyperlipidemia
- Edema
- Frothy urine & fatty casts
May be primary (direct sclerosis of podocytes) or secondary (podocyte damage from systemic disease like diabetes)
**Associated with hyper coagulable state (eg. thromboembolism) due to antithrombin (AT) III los in urine and increased risk of infection (due to loss of immunoglobulins in urine and soft tissue compromise from edema)
19
Q
What are two examples of nephritic-nephrotic syndrome?
A
- Diffuse proliferative glomerulonephritis
2. Membranoproliferative glomerulonephritis
20
Q
What are the LM, IF and EM findings associated with acute post streptococcal glomerulonephritis?
A
LM: glomeruli enlarged and hypercellular
IF: “starry sky” granular appearance / “lumpy-bumpy” due to IgG, IgM and C3 deposition along GBM and mesangium
EF: subepithelial immune complex humps
21
Q
Who gets post streptococcal glomerulonephritis and what type of hypersensitivity reaction is it?
A
Most frequently seen in children; occurs ~2 weeks after group A streptococcal infection of pharynx or skin and resolves spontaneously
Type III hypersensitivity reaction
22
Q
What are the clinical features of post streptococcal glomerulonephritis?
A
- Presents with peripheral and periorbital edema, cola-colored urine, hypertension
- Increased anti-DNase B titers and decreased complement levels
23
Q
What is the classic LM and IF finding associated with rapidly progressive glomerulonephritis (RPGN)?
A
LM and IF: crescent moon shape
Crescents consist of fibrin and plasma proteins (eg. C3B) with glomerular parietal cells, monocytes and macrophages
24
Q
What is the prognosis, clinical presentation and treatment for rapidly progressive glomerulonephritis (RPGN)?
A
Poor prognosis; rapidly deteriorating renal function (days to weeks)
Presents with hematuria/hemoptysis
Treatment: emergent plasmapheresis
25
What are three disease processes that result in rapidly progressive glomerulonephritis (RPGN)?
1. Goodpasture syndrome: type II hypersensitivity with antibodies to type IV collagen in GBM and alveolar basement membrane --> linear IF
2. Granulomatosis with polyangitis (Wegener) --> PR3-ANCA/c-ANCA
3. Microscopic polyangitis --> MPO-ANCA/p-ANCA
26
What are the LM, IF and EM findings associated with diffuse proliferative glomerulonephritis (DPGN)?
LM: "wire looping" of capillaries
EM: sub epithelial and sometimes intramembranous IgG-based Immune Complexes often with C3 deposition
IF: granular
27
What are the two main causes of diffuse proliferative glomerulonephritis (DPGN)?
Due to SLE or membranoproliferative glomerularnephritis
Think: "wire lupus" bc of the "wire looping" feature
Most common cause of death in SLE
**DPGN and MPGN often present as nephrotic and nephritic syndrome concurrently
28
What are the LM, IF and EM findings associated with IgA nephropathy (Berger Disease)?
LM: mesangial proliferation
EM: Mesangial Immune Complex (IC) deposits
IF: IgA-based IC deposits in mesangium
29
What are the clinical associations with IgA nephropathy (Berger Disease)?
- Often presents with renal insufficiency or acute gastroenteritis
- Episodic hematuria with RBC casts
- Renal pathology of Henoch-Schonlein purpura
**NOT to be confused with Buerger disease (thromboangiitis obliterans)
30
What is Alport Syndrome and its associated clinical manifestations?
Mutation in Type IV collagen (most commonly X-linked) leading to thinning and splitting of glomerular basement membrane causing:
- Eye Problems (eg. retinopathy, lens dislocation)
- Glomerulonephritis
- Sensorineural deafness
Think: "Can't see, can't pee, can't hear a buzzing bee"
31
What EM finding is associated with Alport Syndrome?
"Basket-weave" appearance on EM
32
What are the findings associated with Type I Membranoproliferative Glomerulonephritis and what are the causes of Type I?
Subepithelial immune complex deposits with granular IG + "tram-track" appearance on PAS stain and H&E stain due to GBM splitting caused by mesangial ingrowth
Type I may be secondary to hepatitis B or C infection or idiopathic
33
What are the findings associated with Type II Membranoproliferative Glomerulonephritis and what are the causes of Type II?
Intramembraneous IC deposits / "dense deposits"
Type II is associated with C3 nephritic factor (stabilizes C3 convertase --> see decreased C3 serum levels)
34
What are the LM, IF and EM findings associated with Focal Segmental Glomerulosclerosis?
LM: segmental sclerosis and hyalinosis
IF: Nonspecific for focal deposits of IgM, C3 and C1
EM: Effacement of foot process similar to minimal change disease
35
Who commonly gets Focal Segmental Glomerulosclerosis and what are the primary and secondary causes and what are the treatments?
- Most common cause of nephrotic syndrome in Aftrican Americans and Hispanics
- Can be primary (idiopathic) or secondary to other conditions (ie. HIV infection, sickle cell disease, heroin abuse, massive obesity, interferon treatment, chronic kidney disease due to congenital malformations)
- Primary disease has inconsistent response to steroids; may progress to chronic renal disease
36
What are the LM, IF and EM findings associated with Minimal Change Disease (lipoid nephrosis)?
LM: normal glomeruli (lipid may be seen in PCT cells)
IF: negative
EM: Effacement (fusion) of foot processes / look blob-y
37
Who commonly gets Minimal Change Disease, what are the primary and secondary causes and what are the treatments?
- Most common cause of nephrotic syndrome in children
- Often primary (idiopathic) and may be triggered by recent infection, immunization, immune stimulus
- Rarely, may be secondary to lymphoma (eg. cytokine-mediated damage)
- Primary disease has excellent response to corticosteroids
38
What are the LM, IF and EM findings associated with Membraneous Nephropathy?
LM: Diffuse capillary and GBM thickening
IF: Granular as a result of immune complex deposition, nephrotic presentation of SLE
EM: "Spike and Dome" appearance with sub epithelial deposits
39
Who commonly gets Membraneous Nephropathy, what are the primary and secondary causes and what are the treatments?
- Most common cause of primary nephrotic syndrome in Caucasian adults
- Can be primary (idiopathic) or secondary to other conditions (eg. antibodies to phospholipase A2 receptor, drugs like NSAIDS and penacillamine, infections like HBV and HCV, SLE and solid tumors
- Primary disease has a poor response to steroids; may progress to chronic renal disease
40
What LM finding is associated with Amyloidosis and what stain is used?
LM: Congo red stain shows apple green birefringence under polarized light
41
What organ is most commonly involved in systemic amyloidosis and which diseases is it associated with?
Kidney is the most commonly involved organ
Associated with chronic conditions (e.g. multiple myeloma, TB, rheumatoid arthritis)
42
What LM findings are associated with Diabetic Glomerulonephropathy?
LM: mesangial expansion, GBM thickening, eosinophilic nodular glomerulosclerosis (Kimmelstiel-Wilson lesions)
Kimmelsteil-Wilson lesions appear as diffuse, pink glomerulus that looks like an acellular nodule
43
What is the pathology behind Diabetic Glomerulonephropathy?
Nonenzymatic glycosylation of GBM leads to increased permeability and thickening
Nonenzymatic glycosylation of efferent arteriole also leads to increased GFR and mesangial expansion
**This is why diabetic patients have to pee so much, but them on ACE inhibitors as prophylaxis to prevent them from getting this
44
What are two severe complications that can result from kidney stones?
1. Hypronephrosis (atrophy of renal tissue due to compression by ureter)
2. Pyelonephritis (less urine flow makes it easier for bacteria/infection to move up to the kidney)
45
How do kidney stones present clinically?
Presents with unilateral flank tenderness, colicky pain radiating to the groin, hematuria (NO CASTS)
**Treat and prevent by encouraging fluid intake
46
What is the most common kidney stone presentation?
Calcium oxalate stone in patient with hypercalicuria and normocalcemia
47
Do calcium stones precipitate at high or low pH?
High pH: calcium phosphate
Low pH: calcium oxalate
48
Are calcium stones radiopaque or radiolucent on X-ray?
Radiopaque
49
How do calcium crystals appear/what are their characteristic shape?
Envelope or dumbbell-shaped calcium oxalate
50
What causes calcium stones and what are the recommended treatments?
Oxalate crystals can result from ethylene glycol (antifreeze) ingestion, Vitamin C abuse, hypocitraturia, malabsorption (e.g. Crohn's Disease)
Treatment: hydration, thiazides, citrate
51
Do Ammonium Magnesium Phosphate (struvite) stones precipitate at high or low pH?
High pH
52
Are Ammonium Magnesium Phosphate (struvite) stones radiopaque or radiolucent on X-ray?
Radiopaque
53
How do Ammonium Magnesium Phosphate (struvite) stones appear/what are their characteristic shape?
Coffin lid
**Often form staghorn calculi (branched stones that occupy a large portion of the collecting system)
54
What causes Ammonium Magnesium Phosphate (struvite) stones and what is the treatment?
Caused by infection by urease + bugs (eg. Proteus mirabilis, Staphylococcus saprophyticus, Klebsiella) that hydrolyze urea to ammonia leading to urine alkalization
Treatment: eradication or underlying infection, surgical removal of stone
55
Do Uric Acid stones precipitate at high or low pH?
low pH
56
Are Uric Acid stones radiopaque or radiolucent on X-ray?
Radiolucent (cannot be seen on X-ray, but can be seen on US or CT scans)
57
How do Uric Acid stones appear/what are their characteristic shape?
Rhomboid or rosettes
58
What are risk factors for uric acid stones, which diseases are strongly associated with uric acid stones and what is the treatment?
Risk factors: decreased urine volume, arid climates, acidic pH
Often seen in diseases with increased cell turnover such as leukemia
Strong association with hyperuricemia (e.g., Gout)
Treatment: alkalinization of urine, allopurinol
59
Do Cystine stones precipitate at high or low pH?
low pH
60
Are Cystine stones radiopaque or radiolucent on X-ray?
Radiolucent (cannot be seen on X-ray, but can be seen on US or CT scans)
61
How do Cystine stones appear/what are their characteristic shape?
Hexagonal
Think: "Sixtine stones have SIX sides"
62
What causes Cystine stones and what is the treatment?
Hereditary (autosomal recessive) condition in which the cystine-reabsorbing PCT transporter loses function, causing cystinuria. Cystine is poorly soluble, thus stones form in the urine
Mostly seen in children; can form staghorn calculi
Treatment: alkalinization of urine
63
What test can you do to determine if someone has cystine stones?
Sodium cyanide nitroprusside test +
64
What is hydronephrosis and what can it lead to?
Distention/dilation of renal pelvis and calyces, which an lead to compression and possible atrophy of renal cortex and medulla
65
What are the causes of hydronephrosis and where does dilation occur?
Usually caused by urinary tract obstruction (eg. renal stones, BPH, cervical cancer, injury to ureter)
Other causes include retroperitoneal fibrosis, vesicoureteral reflux
Dilation occurs PROXIMAL to the site of pathology
66
When does serum creatinine become elevated in patients with hydronephrosis?
If obstruction is bilateral or if a patient has only one kidney
67
Which cells are affected in Renal Cell Carcinoma and how do they appear?
Originates from PCT cells --> polygonal clear cells filled with accumulated lipids and carbohydrates
68
Who gets Renal Cell Carcinoma and what are two risk factors?
Most common in men 50-70 years old
Increased incidence with smoking and obesity
(most common primary renal malignancy)
69
How does Renal Cell Carcinoma present clinically, how does it spread and where are the two common sites of metastasizes?
- Manifests clinically with hematuria, palpable mass, secondary polycythemia, flank pain, fever, weight loss
- Invades renal vein then IVC and spreads hematogenously
- Metastasizes to lung and bone
70
Renal Cell Carcinoma is associated with a gene deletion on which chromosome?
Gene deletion on chromosome 3 (sporadic or inherited as von Hippel-Lindau syndrome)
Think: "RCC = 3 letters = chromosome 3"
71
Which three hormones are released ectopically/associated with Renal Cell Carcinoma (RCC)?
Associated with paraneoplastic syndromes (eg. ectopic EPO, ACTH, PTHrP)
72
What is the prognosis and treatment for Renal Cell Carcinoma (RCC)?
"Silent" cancer because commonly presents as metastatic neoplasm
Treatment: resection if localized disease; immunotherapy or targeted therapy for advanced/metastatic disease; resistant to chemotherapy and radiation therapy
73
What is a renal oncocytoma, what are its main histological features and clinical symptoms?
- Benign epithelial cell tumor
- Large eosinophilic cells with abundant mitochondria without perinuclear clearing (vs chromophobe renal cell carcinoma)
- Presents with painless hematuria, flank pain and abdominal mass
- Often resected to exclude malignancy (eg. RCC)
74
What is a Wilm's Tumor, who gets it and how does it present?
- Most common malignancy of early childhood (ages 2-4)
- Contains embryonic glomerular structures
- Presents with large, palpable, unilateral flank mass and/or hematuria
75
What mutations and on what chromosome are associated with Wilm's tumors?
"loss of function" mutations of tumor suppressor genes WT1 and WT2 on chromosome 11
76
What two syndrome/complex include Wilm's tumors?
- May be part of Beckwith-Syndrome (wilms tumor, macroglossia, organomegaly, hemihypertropy)
- WAGR complex: Wilm's tumor, Aniridia, Genitourinary malformation, mental Retardation (intellectual disability)
77
What is transitional cell carcinoma of the bladder and how does it present?
- Most common tumor of urinary tract system (can occur in renal calyces, renal pelvis, ureters and bladder)
- Painless hematuria (NO CASTS) suggests bladder cancer
78
What are risk factors for transitional cell carcinoma of the bladder?
Think: "Problems with your Pee SAC"
Phenacetin
Smoking
Aniline dyes
Cyclophosphamide
79
What is the pathology behind squamous cell carcinoma of the bladder and how does it present?
Chronic irritation of urinary bladder --> squamous metaplasia --> dysplasia and squamous cell carcinoma
Presents with painless hematuria
80
What are the risk factors for squamous cell carcinoma of the bladder?
- Schistosoma haematobium infection (Middle East)
- Chronic Cystitis
- Smoking
- Chronic nephrolithiasis
81
How do urinary tract infections (acute bacterial cystitis) present?
- Presents as suprapubic pain, dysuria, urinary frequency, urgency
- Systemic signs (eg. high fever, chills) are usually absent
82
What are the risk factors for urinary tract infections (acute bacterial cystitis)?
- female gender (short urethra)
- sexual intercourse ("honeymoon cystitis")
- indwelling catheter
- diabetes mellitus
- impaired bladder emptying
83
What are the causes of UTIs (acute bacterial cystitis)?
- E. Coli (most common)
- Staphlyococcus saprophyticus --> seen in sexually active young women, but e coli is still more common in this group
- Klebsiella
- Proteus mirabilis (urine has ammonia scent)
84
What are the lab findings for UTIs (acute bacterial cystitis)?
+ Leukocyte esterase
+ nitrates for gram-negative organisms (especially E. Coli)
Sterile pyuria and - urine cultures suggests urethritis by Neisseria gonorrheae or Chlamydia trachomatis (bc both of these organisms are intracellular)
85
What is acute pyelonephritis and which areas of the kidney are most affected?
- Neutrophils infiltrate the renal interstitium
| - Affects the cortex with relative sparing of glomeruli/vessels
86
What are the clinical symptoms/findings of acute pyelonephritis?
Presents with fever, flank pain (costovertebral angle tenderness)
Presents with WBCs in urine +/- WBC casts
CT shows striated parenchymal enhancement
87
What are the causes of acute pyelonephritis?
Ascending UTI (E. Coli most common)
or
Hematogenous spread to the kidney
88
What are the risk factors associated with acute pyelonephritis?
Risk factors include: indwelling catheter, urinary tract obstruction, vesicoureteral reflux, diabetes mellitus and pregnancy
Think: "COPD" for catheter, obstruction, pregnancy, diabetes
89
What are the potential complications of acute pyelonephritis?
Chronic pyelonephritis, renal papillary necrosis, perinephric abscess, urosepsis
90
What is chronic pyelonephritis and what causes it?
The result of recurrent episodes of acute pyelonephritis
Typically requires a predisposition to infection such as vesicoureteral reflux or chronically obstructing kidney stones
91
What are the results/findings associated with chronic pyelonephritis?
Coarse, asymmetric corticomedullary scarring, blunted calyx
Tubules contain eosinophilic casts resembling thyroid tissue (often called "thyroidization of the kidney"
92
What is the pathology behind drug-induced interstitial nephritis (tubulointerstitial nephritis) and what are the presenting symptoms?
- Acute interstitial renal inflammation
- Pyuria (classically eosinophils) and azotemia occurring after the administration of drugs that act like happens, inducing hypersensitivity
- Associated with fever, rash, hematuria, and costovertebral tenderness, but can also be assymptomatic
93
Which drugs cause drug-induced interstitial nephritis (tubulointerstitial nephritis) and when?
Nephritis typically occurs 1-2 weeks after certain drugs (eg. diuretics, penicillin derivatives, proton pump inhibitors, sulfonamides, rifampin) but can occur MONTHS after administration of NSAIDS
94
What is diffuse cortical necrosis and what is it associated with?
- Acute generalized cortical infarction of both kidneys likely due to a combination of vasospasm and DIC
- Associated with obstetric catastrophes (eg. abrupt placentae), septic shock
95
What is acute tubular necrosis and what is the key finding?
Most common cause of acute kidney injury in hospitalized patients; spontaneously resolves in some patients; can be fatal especially during maintenance oliguric phase (increased FENa)
KEY FINDING: Granular "Muddy Brown" Casts
96
What are the three stages of acute tubular necrosis and what are the risks at each stage?
1. Inciting Event
2. Maintenance Phase (oliguric/patient does not generate a lot of urine) lasts 1-3 weeks; risk of hyperkalemia, metabolic acidosis and uremia (b/c H+ and K+ cannot be excreted in the urine)
3. Recovery Phase (polyuric); BUN/serum Creatinine fall and there is a risk of hypokalemia
97
What are the two main insults that can cause ATN?
1. Ischemic Injury secondary to decreased renal blood flow (eg. hypotension, shock, sepsis, hemorrhage, HF). Results in death of tubular cells that may slough into tubular lumen (PCT and thick ascending limb are highly susceptible to injury)
2. Nephrotoxic Injury resulting from toxic substances (eg. aminoglycosides, radiocontrast agents, lead, cisplatin), crush injury (myoglobinuria), hemoglobinuria
98
What is renal papillary necrosis and what are the presenting signs?
Sloughing of necrotic renal papillae causing gross hematuria and proteinuria
Renal papillae are especially susceptible to hypoxia because its farthest away from the arterioles that bring blood supply
99
What are the associations/risk factors for developing renal papillary necrosis?
Think: "SAAD papa with papillary necrosis"
Sickle cell disease or trait
Acute pyelonephritis
Analgesics (NSAIDS)
Diabetes mellitus
100
What is the definition of acute renal failure and what are the three categories?
Acute kidney injury or acute renal failure is defined as abrupt decline in renal function as measured by increased creatinine and increased BUN
Three categories:
1. Prerenal azotemia
2. Intrinsic renal failure
3. Postrenal azotemia
101
What is the pathology underlying prerenal azotemia?
```
Decreased RBF (eg. hypotension) leads to decreased GFR
--> Na+/H20 and BUN retained by the kidney in an attempt to conserve volume --> increased BUN/Creatinine ratio (BUN is reabsorbed, creatinine is not) and decreased FENa
```
102
What is the pathology underlying intrinsic renal failure?
- Generally due to acute tubular necrosis (ATN) or ischemic/toxins
- Less commonly due to acute glomerulonephritis (eg. RPGN, hemolytic uremic syndrome)
- In ATN, patchy necrosis --> debris obstructing tubule and fluid backflow across necrotic tubule --> decreased GFR
- Urine has epithelial granular casts
- BUN reabsorption is impaired --> decreased BUN/Creatinine ratio
103
What is the pathology underlying postrenal azotemia?
Due to outflow obstruction (stones, BPH, neoplasia, congenital abnormalities)
Develops only with BILATERAL obstruction
104
What are the values for urine osmolality, urine Na+, FENa and serum BUN/creatinine for prerenal acute renal failure?
Urine osmolality: > 500 (kidneys are appropriately concentrating the urine)
Urine Na+: 20
105
What are the values for urine osmolality, urine Na+, FENa and serum BUN/creatinine for intrinsic acute renal failure?
Urine osmolality: 20
FENa: > 2%
Serum BUN/Cr:
106
What are the values for urine osmolality, urine Na+, FENa and serum BUN/creatinine for postrenal acute renal failure?
Urine osmolality: 40
FENa: > 1% (mild disease); > 2% (severe disease)
Serum BUN/Cr: varies
107
What are the causes of chronic renal failure?
Hypertension, diabetes mellitus, congenital anomalies
108
What are the consequences of renal failure?
Think: "MAD HUNGER"
```
Metabolic Acidosis
Dyslipidemia (especially increased triglycerides)
Hyperkalemia
Uremia:
- Nausea and anorexia
- Pericarditis
- Asterixis
- Encephalopathy
- Platelet dysfunction
Na+/H20 retention (HF, pulmonary edema, hypertension)
Growth retardation and developmental delay
Erythropoietin failure (anemia)
Renal osteodystrophy
```
109
What is renal osteodystrophy?
Failure of vitamin D hydroxylation, hypocalcemia and hyperphosphatemia leading to secondary hyperparathyroidism
Hyperphospatemia also independently lowers serum Ca2+ absorption by causing tissue calcifications, whereas decreased 1,25 (OH)2 D3 leads to decreased intestinal Ca2+ absorption
Causes subperiosteal thinning of bones
110
What is ADPKD and how does it present?
Formerly adult polycystic kidney disease --> numerous cysts causing bilateral enlarged kidneys ultimately destroy kidney parenchyma
Presents with flank pain, hematuria, hypertension, urinary infection, progressive renal failure
111
What mutations are associated with ADPKD?
Autosomal dominant
Mutation in PKD1 (85% of cases, chromosome 6)
Mutation in PKD2 (15% of cases, chromosome 4)
112
What are complications associated with ADPKD?
Death from complications of chronic kidney disease or hypertension (caused by INCREASED RENIN PRODUCTION)
Associated with berry aneurysms, mitral valve prolapse, benign hepatic cysts
113
What is ARPKD, how does it present, what is it commonly associated with ?
Formerly infantile polycystic kidney disease, presents in infancy; Autosomal Recessive
Associated with Congenital Hepatic Fibrosis
114
What mutation is associated with ARPKD?
PKHD1 mutation
115
What are the associations with ARPKD in utero and beyond the neonatal period?
Significant oliguric renal failure in utero can lead to the Potter sequence
Concerns beyond the neonatal period include: systemic hypertension, progressive renal insufficiency and portal hypertension from Congenital Hepatic Fibrosis
116
What is Medullary Cystic disease and what is the common US finding?
Inherited disease causing tubulointerstitial fibrosis and progressive renal insufficiency with inability to concentrate urine
Medullary cysts usually not visualized, but SRUNKEN KIDNEYS on ultrasound
Poor prognosis
117
What is the difference between simple and complex renal cysts?
Simple cysts = filled with ultra filtrate (anechoic on ultrasound), very common and account for the majority of all renal masses, found incidentally and typically asymptomatic
Complex cysts = include those that are septated, enhanced, or have solid components on imaging and usual require follow-up or removal due to risk of renal cell carcinoma
