RENAL PATHOLOGY -3 Flashcards
This deck covers Congenital and cystic kidney disorders + Urinary tract Obstruction + Chronic kidney disease.
Name one condition associated with formation of the characteristic crystals shown in the attached image.
Hyperuricemia- Gout, Leukemia
The uric acid crystals are described as Diamond/ rhombic/ rosette forms
What is the underlying reason for the typical physical appearance and assoc pulmonary hypoplasia in Potter sequence?
Oligohydramnios and compression while in utero
Identify the type of crystal seen on microscopic exam of a urinalysis specimen
Calcium oxalate crystals: colorless octahedral or “envelope”- shaped crystals which look like small squares crossed by intersecting diagonal lines . Appears dumbbell shaped when viewed from the side.
Define hydronephrosis
dilation of the renal pelvis and calyces associated with progressive atrophy of the kidney due to obstruction to the outflow of urine
What are some ways in which urinary tract obstruction can compromise renal function?
- High pressure in the renal pelvis-→ decreased renal blood flow-→increased renin-→hypertension
- elevated intratubular pressure-→tubular dysfunction-→polyuria, nocturia
- complete obstruction-→elevation in BUN, creatinine, oliguria, anuria i.e post renal azotemia
electrolyte abnormalities associated with chronic kidney disease
hypervolemic hyponatremia
hyperkalemia - due to transcellular shift in acidosis and decreased renal excretion
hypocalcemia- due to decreased synthesis of 1-α-hydroxylase and binding of excess phosphorus with calcium
Two important consequences of a posterior urethral valve abnormality
A. Chronic kidney disease
B. VUR
Staghorn calculi are associated with infection with which specific group of micro-organisms?
Infections by urea-splitting bacteria that Convert urea to ammonia, alkalinizing urine e.g., Proteus
One consequence of hydronephrosis on morphology of renal parenchyma
- Cortical atrophy
- decreased medullary blood flow
Acid base abnormality associated with CKD
Metabolic acidosis
Read the scenario below and deduce whether it would result in unilateral/ bilateral hydronephrosis:
Obstruction is above the level of the bladder
Unilateral hydronephrosis
How does CKD lead to osteomalacia?
Hypovitaminosis D →hypocalcemia →decreased mineralization of osteoid
[bone biopsy shows exaggeration of osteoid seams]
most common etiology of urinary tract obstruction in the newborn male.
Posterior Urethral Valve
Top 3 causes of prevalence of end stage renal disease in the United States
- Diabetes Mellitus
- Hypertension
- Glomerulonephritis
Mineral disorders in chronic kidney disease
diminished production of 1,25-(OH)2D3 (calcitriol, the activated form of vitamin D),
decreased serum calcium
increased serum phosphorus.
increased PTH (secondary hyperparathyroidism)
Simple or complex renal cyst?
Incidentally discovered
Asymptomatic
USG: Well defined, sharp margins, thin walls, anechoic
Simple renal cyst
What is the genetic mutation associated with the condition described below?
Autosomal dominant
Bilateral enlarged kidneys
C/F: Proteinuria, polyuria, CKD
Condition described: Autosomal polycystic kidney disease
Every cell carries a germline mutant allele of either PKD1 or PKD2
Identify the condition being described
congenital absence or shortening of the intravesical portion of the ureter→ ureter enters the bladder at right angles→reflux of urine into ureters during micturition
Vesicoureteral reflux
Why does hypertension occur in chronic kidney disease?
Chronic injury→ nephron loss → decreased perfusion pressure→ release of renin→ increased Angiotensin II→ glomerular hypertension and hyperfiltration
One consequence of hydronephrosis on tubular function
impaired concentrating ability
[obstruction to outflow-→high pressure in renal pelvis-→elevated intratubular pressure-→ tubular dysfunction]
See the attached image. What’s your diagnosis?
Autosomal Dominant (Adult) Polycystic Kidney Disease
List 2 key CVS abnormalities in CKD
- Hypertension\Heart failure and pulmonary edema
- Pericarditis
Read the scenario described. Is it likely to result in a spastic/ flaccid neurogenic bladder?
Spinal lesions at/above T12 (traumatic spinal cord injuries, multiple sclerosis).
Spastic neurogenic Bladder
Which malignancy in women is associated with bilateral hydronephrosis and subsequent renal failure?
Invasive cervical cancer
Identify the congenital anomaly shown in the attached image
Horseshoe kidneys
Give one term that describes the gross morphology shown in the attached image
Hydronephrosis
What would be the morphology of urine crystals associated with a condition wherein there is a genetic defect in the renal reabsorption of amino acids, including cystine?
colorless, refractile, hexagonal plates
Most likely etiologic factor for development of calcium oxalate stones
Hypercalcemia, hypercalciuria
Name one marker of renal dysfunction that is less dependent on age, sex, race, and muscle mass than serum creatinine
Serum cystatin C - Cysteine protease inhibitor that is produced by all nucleated cells. Filtered by the glomerulus but is not secreted.
List 2 radiopaque renal calculi
Calcium oxalate
Magnesium ammonium phosphate (Triple phosphate)
Identify the type of crystal see on microscopic exam of a urinalysis specimen
Magnesium ammonium phosphate stones - coffin lid appearance
colorless prisms with from three to six sides that frequently have oblique ends
Name this pathologic lesion
Mimics a renal neoplasm when unilateral
Composed of islands of undifferentiated mesenchyme, often with cartilage, and immature collecting ducts
Multicystic renal dysplasia
Diagnostic method of choice to identify a VUR
Voiding cystourethrography
Read the scenario below and deduce whether it would result in unilateral/ bilateral hydronephrosis:
Obstructive lesions at /below the level of the bladder
Bilateral hydronephrosis
Morphology of Bone change due to secondary hyperparathyroidism in CKD
Osteitis fibrosa cystica
[increased bone cell activity + peritrabecular fibrosis + cystic brown tumors]
Most common type of renal calculi
Calcium oxalate stones
Most common extra renal congenital anomaly associated with ADPKD
Liver cysts
Type of casts seen on urinalysis in CKD
Waxy casts
Type of anemia seen in CKD and why?
§Normochromic and normocytic anemia- due to decreased production of erythropoietin
List 3 possible causes of death in patients with ADPKD?
- 40%-coronary or hypertensive heart disease
- 25% - infection
- 15% - ruptured berry aneurysm or hypertensive intracerebral hemorrhage
List 2 radiologic hallmarks of CKD
Rugger jersey spine - sclerosis of the vertebral endplates at multiple contiguous levels, producing an alternating dense-lucent-dense appearance , resembling bands of a rugby jersey
Pepper pot skull- multiple tiny well-defined lucencies in the calvaria caused by resorption of trabecular bone in hyperparathyroidism
Mutation in the PKHD1 gene
Gross appearance of kidney: Smooth surface, Cysts with dilated elongated channels present at right angles to the cortical surface
What protein is coded for by this gene?
This is ARPKD. It is assoc with mutations in the PKHD1 gene which codes for fibrocystin
Most common extra renal congenital anomaly associated with ADPKD
Liver cysts
3 common causes of death in ADPKD
- Coronary or hypertensive heart disease
- Infection
- Ruptured berry aneurysm or hypertensive intracerebral hemorrhage
What is the diagnosis?
Mutation in the PKHD1 gene
Gross: Smooth surface, Cysts with dilated elongated channels present at right angles to the cortical surface
Autosomal Recessive Polycystic Kidney Disease
Most likely effect on hydrostatic pressure in outflow obstruction due to BPH
Increased hydrostatic pressure proximal to obstruction
Decreased GFR
