Urinary System- Abnormal Flashcards
Renal calculi (nephrolithiasis): Description
Causes
Symptoms
Diagnosis
Complications
Treatment
Differential diagnosis
Description
The presence of calculi (stones) anywhere in the kidney.
There are different types including – calcium, struvite (often formed in response to infection), uric acid (from food high in purines)
Causes
Stones form when urine becomes concentrated allowing the minerals to crystallise and stick together. So, it is made up of tiny crystals – sharp and painful!
Dehydration can result in concentrated urine
Diet – high levels of salt, animal protein and vitamin C can increase the risk
Family history, history of diabetes
Mainly seen in patients over 30, up to 12% of males and 5% of women
Symptoms
Pain – often severe (renal colic)
Haematuria but not always
Diagnosis
Radiographic features depend on stone composition and modality used.
Some stones seen on AXR cannot be seen on CT
AXR – can see calcium containing stones. Struggle to see uric acid stones
CT – can see almost all stones but some can be really hard to see
US – harder to see small stones
Complications
Pyelonephritis
Hydronephrosis
Treatment
Surgery if:
Large stones (above 5mm)
Long duration of symptoms
Infection / sepsis
Failed conservative management
Differential diagnosis
Gallstones, pancreatic calcifications, phleboliths, renal artery calcification
Ureteric calculi:
Description
Causes
Symptoms
Diagnosis
Complications
Treatment
Differential diagnosis
Description
Any calculi lying within the ureter
Causes
Same as renal
Symptoms
Same as renal
However, pain may be located away from the kidney so patients may have groin pain or can mimic appendicitis
Diagnosis
AXR – can see large radiopaque calculi. Not good for assessing for obstruction or hydronephrosis
CT – gold standard. 99% can be seen over 1mm.
US – useful and no radiation
Complications
Same as renal
Treatment
Hydration and pain relief
Surgery if failed conservative management
Differential diagnosis
Foreign body, phlebolith.
Bladder stones (calculus):
Description
Causes
Symptoms
Diagnosis
Complications
Treatment
Differential diagnosis
Description
Stones found in the bladder!
Causes
Rare. Often form when you don’t fully empty your bladder of urine
3 types
Symptoms
Pain, infection, haematuria
Diagnosis
AXR – dense, radiopaque calculi, often large and often lots. Smooth and rounded
US – they are mobile and echogenic. May also see bladder wall thickening due to inflammation
Complications
Infection, irritation of the bladder wall
Treatment
Surgery
Treatment of the underlying cause
Differential diagnosis
Could be a stone in the distal ureter
Renal cysts:
Description
Causes
Symptoms
Diagnosis
Complications
Treatment
Differential diagnosis
Description
General term for any cystic lesion
Causes
Incidences increased with age
Symptoms
Mostly asymptomatic
Diagnosis
Often found incidentally
CT – round, homogenous, fluid filled with no septations or calcifications
US – round, oval shape with smooth walls, no calcifications
Complications
Size can impair kidney function
Treatment
If asymptomatic they are normally left – sometimes monitored.
Differential diagnosis
Renal cell carcinoma, aneurysm
Polycystic kidneys:
Description
Causes
Symptoms
Diagnosis
Complications
Treatment
Differential diagnosis
Description
Lots of different names
Causes
Genetic – inherited adult cystic renal disease
Symptoms
At 30 approx. 68% of patients will have cysts that can be seen on US
Depends on amount and size – pain, palpable mass, haematuria, hypertension and renal failure
Diagnosis
Generally family history and imaging
It can be really hard to report on imaging due to the amount and size of the cysts
Radiographs – no role
US – quick, no radiation dose, good first line diagnosis
CT – simple cysts appear as rounded structures with HU like water and thin walls.
MRI – most sensitive for small cysts
Complications
End stage renal failure
Treatment
Transplant or dialysis due to ESRF in many patients.
Recurrent urinary tract infections
Cyst haemorrhage / infection
Urinary tract stones
Differential diagnosis
Other inherited cystic disease
Medullary sponge kidneys:
Description
Causes
Symptoms
Diagnosis
Complications
Treatment
Differential diagnosis
Description
Condition where the medullary portions of the collecting systems are dysplastic and dilated
Causes
Developmental defect – affects the formation of the collecting tubules resulting in cystic dilatation of the medullary portions of the collecting ducts
Associated with Ehlers Danlos syndrome and other congenital syndromes
Symptoms
UTI’s
Haematuria and urinary tract calculi
Diagnosis
Radiograph / CT – pyramid shaped clusters of small calcifications.
US- will see an echogenic pyramids with or without calcifications
Complications
Medullary nephrocalcinosis (80%) of cases
Treatment
No specific treatment
Mainly focuses on managing the urinary tract infections and renal calculi
Differential diagnosis
Other causes of calcifications
Renal cell carcinoma (RCC):
Description
Causes
Symptoms
Diagnosis
Complications
Treatment
Differential diagnosis
Description
Primary malignant adenocarcinoma derived from the renal tubular epithelium
Most common renal tumour
Causes
Risk factors include smoking, hypertension
Associations with some inherited syndromes and sickle cell disease
Symptoms
Haematuria
Flank pain
Palpable mass
Patients can also develop hypertension and polycythaemia
Diagnosis
US – not as sensitive as CT or MRI. Can be hard to stage on US. RCC can have many different appearances on US making it hard to give a definitive diagnosis
CT – non-con looks like a soft tissue mass (20-70HU). May also see necrosis or calcification. Post contrast, the mass will enhance
MRI – best imaging for diagnosing and staging
T1- heterogenous
T2 – appearances differ depending on the histology
PET/CT – limited value due to the excretion of the FDG from the kidneys which can obscure the lesion
Complications
Over 30% have metastatic disease at time of initial presentation – most common sites are lungs, bone, lymph nodes, adrenals and brain
Treatment
Nephrectomy – full or partial
Differential diagnosis
Adrenal tumours, renal abscess, renal lymphoma
Bladder cancer – transitional cell carcinoma (TCC):
Description
Causes
Symptoms
Diagnosis
Complications
Treatment
Differential diagnosis
Description
There are different types
TCC – most common cancer of the bladder and the entire urinary system
Causes
Risk factors – treatment with certain chemotherapy drugs, smoking, environmental triggers
Symptoms
Haematuria
Depending on location – hydronephrosis, pain and urinary retention
Diagnosis
Cystoscopy and biopsy
Aim of imaging – identifying the tumour, staging, evaluation of distant metastases and surveillance.
US – limited
CT – focal thickening or extension into adjacent structures.
MRI – best for staging
Pet – FDG excreted in urine and accumulates in bladder making PET not useful in diagnosing urinary tract tumours. Can identify distant metastases though.
Complications
Metastases
Treatment
Depends on staging
Local tumours can be diagnosed by resection and chemotherapy.
Invasive tumours require cystectomy and chemotherapy and radiotherapy
Differential diagnosis
Other types of bladder tumour
Chronic kidney disease:
Description
Causes
Symptoms
Diagnosis
Complications
Treatment
Differential diagnosis
Description
Also called chronic renal failure
Abnormal kidney structure or function, typically seen by a progressive loss of glomerular function (eGFR less than 60ml/min for 3 consecutive months)
Causes
Diabetes, hypertension, polycystic kidney disease
Symptoms
Depends on the aetiology – may have no symptoms until there are serious complications
Diagnosis
No specific imaging features
Long standing CKD on US may look like a thin renal cortex, smaller kidney size, marginal irregularities
Complications
Oliguria and anuria
Volume overload
Weight loss
Fatigue
Hypertension
Anaemia
Treatment
Stage 3 CKD patients are more than 20 times more likely to die of a cardiovascular event than reach end stage renal disease. Chronica vascular disease is a common
complication
Patients may need dialysis, renal transplant
Chronic kidney disease: Pathophysiology
CKD is the end stage for any cause of severe and long standing kidney injury.
Damage to the kidneys reduces the number of functioning nephrons which makes the kidney adapt.
There is hyperfiltration at the glomeruli leading to proteinuria.
To carry out this hyperfiltration there is activation of the renin-angiotensin-aldosterone system causing an increase in blood pressure.
The increase in capillary pressures causes chronic inflammation which reduces the filtration ability of the glomerulus and this is your reduces eGFR
Adrenal pathology (calcifications and tumours):
Description
Causes
Symptoms
Diagnosis
Complications
Treatment
Differential diagnosis
Description
There are a large number of adrenal tumours both benign and malignant
Often found incidentally
Adrenal adenoma is the most common adrenal lesion
Causes
No definite cause but frequency increases with age
Symptoms
95% or more are asymptomatic.
If patients have hyperfunctioning adrenal gland then they will have manifestations of excess hormone secretion – Cushing syndrome
Diagnosis
Imaging is important for assessment
Correlation with previous imaging is really important to check growth over time
CT – can have typical features (small (less than 3cm) and low density with smooth borders
Or atypical – haemorrhage, calcification, necrosis, large
MRI – most accurate for diagnosis.
Complications
Treatment
If there is hormone disruption, the tumour needs resecting.
Small tumours may be left and monitored
Differential diagnosis
Other rare adrenal lesions
Why don’t we give contrast to people with low eGFR’s?
The risk of contrast induced acute kidney injury is highest in patients with the lowest renal function.
Usually presents 24-48hours of exposure to contrast with elevation in creatinine levels.
Contrast is toxic to the tubular epithelial cells leading to necrosis and apoptosis.
There is vasoconstriction leading to medullary ischaemia.
There is some debate about the impact of newer contrast media and whether withholding imaging in these patients causes more complications.
IV hydration is the best way to mitigate the effects
Description
Causes
Symptoms
Diagnosis
Complications
Treatment
Differential diagnosis
What is Ureterostomy / urostomies?
This is the creation of a stoma for a ureter or kidney.
It diverts the flow of urine away from the bladder when the bladder has been removed or is not functioning.
2 types
Ileal conduit – ureters are detached from the bladder and joined to a small section of the ileum.
Ureterostomy – ureters are detached from the bladder and one or both are brought to the surface as a stoma.
What is Peritoneal dialysis?
Dialysis is a procedure to remove waste products and excess fluid from the blood when the kidneys aren’t functioning.
Usually done while waiting for a renal transplant.
Peritoneal dialysis uses the peritoneum as the filter instead of a machine.
Tube is placed into the peritoneal cavity.
Fluid is pumped through the cavity and the used fluid is drained a few hours later.
Normally done 4 times a day for 30mins
