Presentation of Diseases of the Kidneys and urinary tract Flashcards
What makes up the upper urinary tract?
Kidneys
Ureters
What makes up the lower urinary tract?
Bladder
Bladder outflow tract - urethra
Define Oliguria
Abnormally small amounts of urine
Urine output <0.5ml/kg/hour
Define Anuria
Absolute anuria - No urine output
Relative anuria - <100ml/24 hours
Define Polyuria
Urine output >3L/24 hours
Define Nocturia
Waking up at night ≥1 occasion to micturate
Define Nocturnal polyuria
Nocturnal urine output >1/3 of total urine output in 24 hours
What is the RIFLE staging criteria used for?
Stages of acute Kidney injury
What does the R in RIFLE stand for?
Risk - Increase in serum creatinine level (1.5x) or decrease in GFR by 25%, or UO <0.5 mL/kg/h for 6 hours
What does the I in RIFLE stand for?
Injury - Increase in serum creatinine level (2.0x) or decrease in GFR by 50%, or UO <0.5 mL/kg/h for 12 hours
What does the F in RIFLE stand for?
Failure - Increase in serum creatinine level, or decrease in GFR by 75%, or serum creatinine level >355μmol/L with acute increase of >44μmol/L; or UO <0.3 mL/kg/h for 24 hours, or anuria for 12 hours
What does the L in RIFLE stand for?
Loss - Persistent AKI or complete loss of kidney function >4 weeks
What does the E in RIFLE stand for?
End-stage kidney disease - complete loss of kidney function >3 months
Functions of the kidney (6)
Endocrine functions Body fluid homeostasis Electrolyte homeostasis Acid-base homeostasis Regulation of vascular tone - BP Excretory functions - waste + drugs
How does the kidney perform acid-base balance?
Excrete H+
Generate HCO3-
Clinical Presentation of chronic renal failure
Asymptomatic (found on blood and urine testing)
Tiredness
Anaemia
Oedema
High BP
Bone pain due to renal bone disease or myeloma
In advanced renal failure: Pruritus Nausea/vomiting Dyspnoea Pericarditis Neuropathy Coma - if untreated
When might the ureter be damaged in surgery?
It can be inadvertently cut or tied during hysterectomy (removal of uterus) or colon resection
Hereditary conditions affecting the ureter
Pelvic ureteric junction (PUJ) obstruction
Vesicoureteric junction (VUJ) reflux
What can cause intraluminal obstruction in the ureters?
Kidney stone
Blood clot
What can cause intramural (within the walls) obstruction in the ureters?
Scar tissue
Transitional cell cancer
What can cause extraluminal obstruction in the ureters?
Pelvic mass
Lymph nodes
Presentation of ureteric diseases (5)
Pain (eg. renal colic)
Pyrexia
Haematuria
Palpable mass (ie. hydronephrosis)
Renal failure (only if bilateral obstruction or single functioning kidney)
Types of bladder inflammation
Interstitial cystitis
Colonic diverticulitis resulting in colo-vesical fistula (an open connection between the colon and the bladder) causing infection and other complications
Types of bladder cancer
TCC of the bladder
Squamous cell carcinoma of the bladder
Name a neurological bladder disease
Neurogenic bladder dysfunction
Presentation of bladder diseases
Pain (suprapubic) Pyrexia Haematuria Lower urinary tract symptoms (LUTS) Recurrent UTIs Chronic urinary retention (due to bladder underactivity) Urinary leak from vagina (i.e. vesico-vaginal fistula) Pneumaturia (i.e. colo-vesical fistula)
Causes of Lower urinary tract symptoms
Bladder pathology e.g UTI, interstitial cystitis, bladder cancer
Bladder outflow obstruction e.g enlarged prostate
Pelvic floor dysfunction
Neurological causes e.g neurogenic bladder dysfunction
Systemic disorders e.g chronic renal failure, cardiac failure, DM, diabetes insipidus
Where is the micturition centre found?
In the pons
Function of the cortical centre in control of micturition
Bladder sensation and conscious inhibition of micturition
Which spinal nerves perform the micturition reflex?
S2-S4
What are the 2 phases of the micturition cycle?
Storage phase (or filling) Voiding phase
Infections/inflammation of the bladder outflow tract (2)
Prostatitis
Balanitis - inflammation of the glans of the penis - can cause narrowing of the urethra
How can damage to the bladder outflow tract occur?
Pelvic floor damage after traumatic vaginal delivery or hysterectomy
Urethral injury from catheterisation
Pelvic fracture
What is a hysterectomy?
A hysterectomy is a surgical procedure to remove the uterus.
Cancers of the Bladder outflow tract in Males
Prostate cancer
Penile cancer
Obstructive diseases of the bladder outflow tract
Primary bladder neck obstruction
Benign prostatic enlargement (BPE) causing obstruction
Urethral stricture
Meatal stenosis
Phimosis - foreskin is too tight to retract it
Presentation of bladder outflow tract diseases
Pain (suprapubic or perineal)
Pyrexia
Haematuria
Lower urinary tract symptoms (LUTS)
Recurrent UTIs
Acute urinary retention
Chronic urinary retention
What are some Lower urinary tract symptoms?
Voiding or obstructive symptoms such as hesitancy, poor flow, straining, prolonged micturition, feeling of incomplete bladder emptying, dribbling
What is Acute urinary retention?
A painful inability to void with a palpable and percussible bladder
Residuals vary from 500ml to 1 litre
What is the main risk factor for Acute urinary retention
Benign Prostatic Obstruction
Other causes of acute urinary retention
UTI Urethral stricture Alcohol excess Post-operative Acute surgical or medical problems
What is the immediate treatment for acute urinary retention?
Catheterisation (either urethral or suprapubic)
What is chronic urinary retention defined as?
A painless, palpable and percussible bladder after voiding
Patients often able to void but with residuals ranging from 400ml to >2 litres depending on stage of condition
What is the main aetiological factor of chronic urinary retention?
Detrusor underactivity - can be primary or secondary
How does chronic urinary retention present?
Presents as LUTS or complications e.g UTI, bladder stones, overflow incontinence, post-renal or obstructive renal failure.
Treatment for chronic urinary retention
Asymptomatic patients with low residuals do not necessarily need treatment
Patients with symptoms or complications need treatment (but no role for medical therapy!)
Immediate treatment for chronic urinary retention
Immediate treatment is catheterisation (either urethral or suprapubic initially, followed by clean intermittent self-catheterisation if appropriate
What is CISC?
Clean intermittent self-catheterisation (CISC) = Gold standard in bladder management
Intermittent insertion of a catheter into the bladder by the patient in order to assist drainage of the urine when normal voiding is not possible.
What are the 2 types of diuresis (excessive urine production) that may occur if high-pressure chronic urinary retention persists?
Physiological (usually <200ml/hour)
Pathological (usually >200ml/hour)
Post-obstructive diureses dangers
At risk of severe dehydration, electrolyte imbalances, hypovolemic shock, and even death if fluid and electrolyte replacement is not initiated
Diagnosis of UTI requires what?
Microbiological evidence and symptoms/signs
2 types of UTI
Uncomplicated UTIs (young sexually active females only with clear relation to sexual activity)
Complicated UTIs (everyone else!) - these always need to be investigated
Definition of a UTI
Infection affecting urinary tract (including kidneys, bladder, prostate, testis and epididymis)
Investigations done for UTI
MSSU/CSU - mid stream samples of urine, catheter sample
Lower tract: flow studies, residual bladder scan, cystoscopy
Upper tract: USS kidneys, IVU/CT-KUB, MAG-3 renogram, DMSA scan
What is a DMSA scan?
Dimercapto succinic acid => a radioisotope that goes directly to the kidneys once inside the body and only stays radioactive for a few hours
Emergencies related to urinary tract diseases (11)
Acute renal failure
Sepsis due to UTI +/- upper or lower urinary tract obstruction
Renal colic - pain you get when urinary stones block part of your urinary tract.
Severe haematuria causing haemorrhagic shock
Metastatic disease causing metabolic derangements (eg. hypercalcaemia from bony metastases), spinal cord compression from vertebral metastases, etc.
Acute urinary retention
Chronic high-pressure urinary retention
Iatrogenic injury/Trauma to upper or lower urinary tracts, penis and testis
Testicular torsion
Phimosis - only affects uncircumcised males - foreskin becomes swollen and stuck
Priapism - persistent and painful erection of the penis