Renal Pathology Pt. 4 Flashcards
what is renal agenesis?
bilateral is incompatible with life
unilateral - single kidney hypertrophies to compensate
what is renal hypoplasia?
failure of the kidneys to develop to normal size
bilateral is possible but unilateral is more likely
what is an ectopic kidney?
kidney not present at the usual paravertebral retroperitoneal site but present somewhere along the normal path of the ureter
what is a potential complication of ectopic kidney?
infection due to obstruction
what is a horseshoe kidney?
fusion of the lower or upper poles of the kidneys
what are the cystic diseases of the kidney?
multicystic renal dysplasia polycystic kidney disease medullary cystic disease acquired cystic disease localized renal cysts hereditary malformation syndromes glomerulocystic disease extra-parenchymal renal cysts
what is adult/ AD polycystic kidney disease?
AD mutation in PKD1 (85%) or PKD2 (15%) which encodes polycystin
results in chronic renal failure beginning at age 40-60
what morphological changes are associated with adult polycystic kidney disease?
large, multicystic kidneys
liver cysts
berry aneurysms
what are the clinical features of adult polycystic kidney disease?
hematuria flank pain UTI renal stones HTN
what is infant/ AR polycystic kidney disease?
AR mutation in PKHD1 encoding fibrocystin
may result in early death
what are the morphological changes associated with AR polycystic kidney disease?
enlarged, cystic kidneys at birth
what are the four clinical subtypes of AR polycystic kidney disease?
Perinatal * most common - death several hours after birth
Neonatal - death several months after birth
Infantile - death in early childhood
Juvenile - death during adolescence
what is medullary sponge kidney?
benign medullary cysts on excretory urography
what are the clinical features of medullary sponge kidney?
hematuria
UTI
recurrent renal stones
what is juvenile nephronophthisis?
AR disorder
presents as progressive renal failure in childhood
what are the morphological changes associated with juvenile nephronophthisis?
corticomedullary cysts
shrunken kidneys
what are the clinical features of juvenile nephronophthisis?
salt wasting
polyuria
growth retardation
what is adult-onset nephronophthisis?
AD
presents as chronic renal failure in adulthood
what are the morphological changes associated with adult-onset nephronophthisis?
corticomedullary cysts
shrunken kidneys
what are the clinical features of adult-onset nephronophthisis?
salt wasting
polyuria
what are simple cysts?
benign cystic lesions within the kidneys causing microscopic hematuria
what is acquired renal cystic disease?
cystic degeneration in end-stage kidney disease resulting in dialysis dependence
what are the clinical features of acquired renal cystic disease?
hemorrhage
erythrocytosis
neoplasia
what is multicystic renal dysplasia?
irregular kidneys with various sized cysts
associated with other renal anomalies
results in renal failure if bilateral
surgically curable if unilateral
what are the major clinical features of AR polycystic kidney disease?
cystic collecting ducts
hepatic fibrosis
what renal anomalies are commonly seen with multicystic renal dysplasia?
ureter agenesis
ureteropelvic obstruction
perinatal mass
what is nephrolithiasis?
kidney stones
who is prone to developing nephrolithiasis?
men between age 20-30
what is the clinical presentation of nephrolithiasis?
renal colic
ulceration and bleeding of ureter (hematuria)
obstruction of urinary flow (anuria/oliguria)
which size of stone is most hazardous: small or large?
small because they can enter the ureter
what is the most common type of stone?
calcium oxalate and phosphate
what predisposing condition is associated with calcium oxalate and phosphate stones?
idiopathic hypercalciuria
what factors predispose a patient to kidney stone formation?
increased concentration of stone constitutes
changes in urine pH
decreased urine volume
presence of bacteria
generally, what is the clinical presentation of benign renal neoplasms?
rarely cause clinical problems and are usually discovered as incidental findings on imaging studies
what is the most common benign kidney neoplasm?
renal papillary adenoma
are renal papillary adenomas always benign?
no, once they are greater than 1 cm they are classified as low-grade renal cell carcinoma
what is seen histologically in renal papillary adenoma?
acidophilic cytoplasm (not clear)
papillae
thin fibrovascular cores
what is the origin of renal oncocytoma?
arises from intercalated cells of the renal cortical collecting ducts
what is the clinical presentation of renal oncocytoma?
benign lesions without symptoms
typically present in adulthood
rarely become invasive/metastatic
ddx: renal cell carcinoma
what are the morphological features of renal oncocytoma?
mahogany-brown lesion that is well-circumscribed with central stellate scar
what are the histological features of renal oncocytoma?
abundant acidophilic, granular cytoplasm
may show alveolar, nesting, tubular or solid pattern
what condition are renal angiomyolipomas strongly associated with?
tuberous sclerosis complex (AD)
LoF mutation in TSC1 or TSC2 tumor suppresor genes
what is the clinical presentation of renal angiomyolipomas?
may occasionally rupture and cause massive hemorrhage
initial presentation may be hypovolemic shock
what are the histological features of renal angiomyolipomas?
thick-walled blood vessels (angio)
smooth muscle (myo)
fat (lipo)
what is the most common malignant tumor of the kidneys?
renal cell adenocarcinoma
what risk factors are associated with RCC?
males age 60-80 cigarette smoking (2x) HTN obesity estrogens asbestos CKD tuberous sclerosis acquired cystic disease
what hereditary conditions are associated with RCC?
Von Hippel-Lindau syndrome
Hereditary clear cell carcinoma
Hereditary papillary carcinoma
what is the most common form of RCC?
sporadic clear cell (80%)
hereditary clear cell carcinoma is associated with what mutations?
LoF VHL (tumor suppressor gene) due to deletion/translocation on short arm of Chr. 3
what mutations are associated with sporadic and hereditary papillary renal cell carcinoma?
trisomy 7, 16 and 17
Loss of Y which results in activation of MET proto-oncogene
what is the major morphological difference between sporadic and hereditary RCC?
hereditary forms have multiple lesions
what is the classic triad of RCC presentation?
hematuria
costovertebral pain
palpable flank mass
why is RCC considered one of the “great mimics”?
it has a tendency to cause systemic symptoms unrelated to the kidney
reaches large size and metastasizes before local symptoms occur
what type of RCC has the best prognosis?
chromophobe RCC
what mutation is associated with chromophobe RCC?
Xp11 translocation
what is the typical mode of spread for RCC?
hematogenous
what are the morphological changes associated with RCC?
yellow-ish, spherical neoplasm in one pole of the kidney
what histological changes are associated with clear cell RCC?
clear cytoplasm (collagen +lipid) sharply delineated cell membrane termed "hypernephroma"
what histological changes are associated with papillary RCC?
papillae and foamy macrophages
what histological changes are associated with chromophobe RCC?
pale, eosinophilic cells arranged in solid sheets
well-defined cell membranes
faintly granular cytoplasm with perinuclear clear halos
cell concentrate around blood vessels
what is urothelial carcinoma of the kidney?
cancer that originates from the urothelium of the renal pelvis
associated with analgesic and tubulointerstitial nephropathy
poor prognosis
what is the clinical presentation of urothelial carcinoma?
hematuria
may block urinary outflow ad cause hydronephrosis
50% of patients have concomitant bladder tumors
what is the most common renal tumor in children?
Wilms Tumor
what is the clinical presentation of a wilms tumor?
large abdominal mass
pain
microscopic hematuria
HTN
what familial syndromes are associated with Wilms tumors?
WAGR
Denys Drash
Beckwith-Wiedemann
which familial syndromes are associated with a LoF mutation to WT1?
WAGR and Denys-Drash
what is the presentation of WAGR?
genitourinary malformation
Wilms tumor
what is the presentation of Denys-Drash?
Gonadal tumor
gonadal dysgenesis
early-onset nephropathy
Wilms tumor
what is the presentation of Beckwith-Wiedemann?
macroglossia organomegaly hemihypertrophy omphalocele adrenal cytomegaly wilms tumor
what are the two histomorphologies of Wilms tumors?
typical triphasic
anaplastic
which Wilms tumor histomorphology has a more favorable outcome?
typical triphasic
what is seen on histology in a triphasic Wilms tumor?
spindle-shaped cells
immature tubules
densely packed small blue cells
what morphological changes are associated with a wilms tumor?
well-circumscribed
tan-grey color
large, expansile tumor in the lower pole
what is the most critical prognostic element for a wilms tumor?
presence or absence of diffuse anaplasia
what primary cancers are known to metastasize to the kidneys?
breast lung melanoma GI pancreas