Urinary Tract Congenital Anomalies, Cystic Disease, Urolithiasis and Obstructive Diseases Flashcards
What percentage of renal failure in children is caused by congenital kidney malformations?
20%
What percentage of people are born with potentially significant malformation of the kidney/urinary tract?
10%
What percentage of chronic renal failure is due to ADPKD?
10%
What are the types of malformation of the kidneys?
Agenesis of the kidney
Hypoplasia
Ectopic kidneys Horseshoe kidneys
What is kidney hypoplasia?
Formed kidneys but very small
What is ectopic kidneys?
Kidneys that are misplaced
What is horseshoe kidney?
malformed kidneys that join together and never separate forming a horseshoe shape
What causes agenesis of the kidney?
Major disruption of metanephric development at an early stage
What is potter’s syndrome?
Bilateral agenesis of kidneys.
What happens to babies without kidneys?
They develop without much amniotic fluid around it. This condition is called oligohydramnios.
They also get hypoplastic lungs if there is not enough amniotic fluid to breath in for them to open
What does potter’s facies refer to?
A particular appearance associated with low exposure to amniotic fluid.
What does potter’s facies look like?
Large low set ears
Wide set eyes
Flattened nose
Receding chin
Prominent skin fold below the eyes
What does unilateral agenesis do to foetus?
Usually asymptomatic
What happens to the present kidney in unilateral agenesis?
It undergoes compensatory hypertrophy.
What happens to the ureter of the abscent kidney?
It disappears completely
What causes ectopic kidneys?
Kidneys usually ascend during development to their position and end up staying around the pelvis.
What are the cystic diseases of the kidney?
Cystic renal disease
Polycystic kidney disease (autosomal dominant PKD and autosomal recessive PKD)
What are simple renal cysts?
Very common in normal kidneys especially people older than 50 years old.
Usually they cause no symptoms or signs
Occasionally they can rupture, cause haematuria, pain, abdominal mass, infection, and hypertension.
How are cystic renal lesions diagnosed as tumours?
Multiple septa
Thickened cyst
Solid areas within or around the cyst
What is cystic renal dysplasia?
Malformation of the kidney results inirregular cysts of varying sizes in the kidneys and is a common cause of an abdominal mass in infants
What kind of cells can be found in cystic renal dysplasia?
Persistence of abnormal structures like cartilage and mesenchyme
How do people get polycystic kidney disease?
It’s a congenital defect a dominant form (1 in 500 live births 10% of end stage renal failure have this disease) and recessive form.
What happens to cysts over time in ADPCK?
They grow continuously
At what age do patients present with ADPCK?
Patients start experiencing symptoms between 30 and 50 years old.
What are the symptoms of ADPCK?
Flank pain due to abdominal mass or renal stones
Pain from haemorrhage into a cyst
Haematuria
Hypertension
What are other associated congenital abnormalities associated with APCKD?
Cysts in liver, pancreas, spleen, and lungs
Intracranial berry aneurysms
Mitral valve prolapse
How are cysts different in Autosomal recessive polycystic kidney disease?
Smooth kidneys that have smaller cysts.
They also get cysts on the liver causing fibrosis
Autosomal recessive PKD:
rare and presents early in life
What is obstructive uropathy?
Obstruction of urine to the urinary tract
What are the modes of damage caused by obstructive uropathy?
Acute (stone) / chronic (prostate enlargement)
Partial / complete
Unilateral / bilateral
Any level from the urethra to the renal pelvis
Intrinsic / Extrinsic
What is a common cause of extrinsic compression of the ureter?
Growth of lymph nodes caused by lymphoma
What are some common causes of obstructive uropathy?
- Congenital anomalies such as posterior urethral valves
- Urinary calculi
- Benign prostatic hypertrophy
- Tumours of prostate bladder lymph nodes and inflammation
- Sloughed renal papillae (renal papillae can just die and pop off and block shit) / blood clots
- Normal pregnancy
Uterine prolapse and cystocoele
Functional causes such as defects in muscle wall
*: means common
What happens to kidneys when obstruction takes place?
They kidneys get larger
Renal pelvis and calyces get larger
Ureters get big
Hydronephrosis
Bladder can get very thick
What does hydronephrosis refers to?
Water inside kidney
Distension of the walls and in turn can lead to atrophy of the kidney by squishing the renal parenchyma
What are the symptoms of obstructive uropathy?
Pain from dilation of the renal capsule/ureter/bladder
UTIs
Urinary calculi (lead to precipitation of stuff in urine)
Renal failure (can’t concnetrate urine because kidney is failing)
Partial bilateral obstruction causes an inability to concentrate urine
Complete bilateral obstruction can be fatal
What age groups get kidney stones most commonly?
20 - 30
Who gets urolithiasis most commonly?
Men in their 20s with a family history (ME YAY….)
What are the types of kidney stones?
Calcium oxalate
Uric acid
Struvite (associated with infections)
Calcium phosphate
Others
What causes people to develop kidney stones?
Stones are solutes that occur in amounts too high to stay dissolved in urine so solutes precipitate and aggregate to form concretions (stones)
What are the risk factors for calcium oxalate stones?
Dehydration
Hypercalciuria (with or without hypercacaemia)
Hyperoxaluric (odd diet into spinach, rhubarb, oxalate foods in general i.e superfoods)
Hyperuricosuric
Low urine volume
What causes uric acid stones?
Dehydration
Acidic urine
Hypericaemia
Chronic diarrhoea
Diabetes
Increased urinary excretion of uric acid (So anything that leads to rapid cell death and birth can cause it due to increased metabolism)
What are struvite stones?
UTIs such as proteus and klebsiella have properties that can split urea in the urine creating ammonia which alters pH of urine which causes magnesium ammonium phosphate precipitation and causes formation of a cast of renal pelvis as well as caluses which come from tissue of renal pelvis.
These stones are often called staghorn calculi due to filling of calyceal space in the kidney.
What are the complications of urolithiasis?
Silent often (they can sit there for a long time without symptoms)
If they pass into ureters they are very painful and cause bleeding
Ulceration and bleeding
Infection
What is the pain associated with renal calculi known as?
Renal colic
Where is pain associated with in renal colic?
Excruciating intermittent pain which radiates from the flank to the groin
What other symptoms do people with renal colic get?
Urinary urgency
Restlessness
Haematuria
Sweating
Nausea
Vomiting
Summary
Structural or functional hindrance of urine flow which can lead to renal dysfunction
Can occur at any point in the urinary tract or can affect one or both kidneys
Comon cause is stones
Common presentation of stones is renal colic
Complications of renal colic include infection and renal failure
