Lower urinary tract and UTIs Flashcards
What are the differences between the upeer and lower urinary tracts?
Lower= bladder and urethra
Upper= bilateral collecting systems and ureters
Why is there thicker bladder muscles in males?
The male bladder has a prostate gland below it- causes harder resistance for urine to pass through, so bladder muscles are thicker
What are the 3 layers of the bladder?
Urothelium- multilayered and has a barrier function
Lamina propria- functional centre, controls urothelium and detrusor muscles. Blood, vessels and nerve fibres are found here
Detrusor muscle- smooth and arranged in bundles.
What passively passes through the bladder/
It is not completely waterproof but it does resist water passage
There is passive passage of urea, Na+ and K+
How is voluntary voiding controls?
The spinobulbar reflex is modulated by the pontine micturition centre (PMC) in the pons.
Is known as Barrington’s nucleus
Also mediated by Onuf’s nucleus in the sacral area
What happens when voiding is initiated?
There is coordination of detrusor contraction and external urethral spihincter and urethral relaxation
What type of feedback loop is voiding controlled by?
Voiding is controlled by a positive feedback loop, as detrusor muscles contract, higher functions send efferent signals to increase detrusor contraction
What nerves are involved in volition?
Parasympathetic and pudendal
What is facilitation of voiding?
Early voiding e.g. in anxiety caused by higher centres
What are the excitory and inhibitory neurotransmitters involved in volition?
Excitory= ACh
Inhibitory= GABA and glycine
What can be used to check voiding patterns?
Can use frequency/volume chart which shows frequency, volumes passed and nocturia
Can also use a bladder diary that also shows input
What are lower urinary tract symptoms split into?
- STORAGE= urgency, frequency, nocturia and urinary incontinence
- VOIDING= hesitancy, poor flow, intermittency, terminal dribbling
What do storage symptoms reflect?
They reflect increased urinary production or decreased storage capacity
Could be excess fluid intake, MS, DM/DI
What is nocturia and what are the causes?
Nocturia- nocturnal frequency. Normal is < 2x a night. Caused by ageing bladder, bladder onstruction, dietary habits, decreased compliance
Renal concentrating ability decreases with age- less is absorbed so more urine produced
What are the voiding symptoms and what causes them?
Poor flow, hesitancy and dribble
Can be due to bladder outlet obstruction, urethral stricture (narrowing)
May also be due to an underactive/ hypocontractile bladder
What is incontience and what are the two types?
Defined as ‘involuntary loss of urine that is a social or hygienic problem and is objectively demonstrable
- Urge incontience= Involuntary loss of urine associated with strong desire to void (detrusor contraction)
- Stress incontience= –Involuntary loss of urine when intra-abdominal pressure rises without detrusor contraction eg with coughing, sneezing, laughing, straining, exerting
What is the international prostate symptom score?
Combines 7 questions and quality of life symptoms to get a score
What is a UroFlowMeter?
Uroflowmetry is a test that measures the volume of urine released from the body, the speed with which it is released, and how long the release takes.
What is Urodymanic assessment?
Pressure transducers placed to measure pressure in bladder and rectum. Subtracting rectal (abdominal) pressure from bladder = detrusor activity.
Helps find the cause
What does a normal urodynamic trace look like?
What does detrusor overactivity look like in a urodynamic trace?
What is the treatment for overactive detrusor activity?
Anti-muscarinic therapy or botox therapy
What does stress incontinence look like on a urodynamic trace?
What does high detrusor pressure associated with low urinary output volume indicate?
Bladder outflow obstruction
What is the stepwise pattern of outflow obstruction?
- Storage symptoms may come first then voiding symptoms and finally decompensation of the detrusor muscles
- Can lead to residual urine, chronic retention, bladder failure and renal failure
What is the treatment for an overactive bladder?
Lifestyle; cutting down on alcohol and caffine
Give anti-muscarinics and if these do not work intradetrusor botox
What is the treatment of stress incontinence?
Pelvic floor exercise, weight loss, surgery
What is the treatment for bladder outlet obstruction?
alpha blockers, 5 alpha reductase inhibitors or surgery
What are the two types of urinary tract infection?
What are the risk factors for UTIs?
- Females (due to anatomy)
- Those with a previous UTI
- Sexual activity
- Diabetes (pathogens like high levels of glucose)
- Obesity (anatomy changes)
- Genetic susceptibility
- Older age- cognitive impairement and oestrogen deficiency
What is the most common cause of secondary bloodstream infections?
Catheter associated UTIs (CAUTIs)
What factors may cause a patient to develop a complicated UTI?
Urinary obstruction- vaginal prolapse, prostatic enlargement
Urinary retention- neurological disease
Immunosuppressed patients
Those with renal failure
Pregnancy
Prescence of foreign bodies e.g. catheters
What are the most common pathogens to cause UTIs?
1 Uro-pathogenic E coli
#2 K pneumoniae
#3 Enterococcus spp.
How do the pathogens cause an infection?
Have pili which helps adhere to the bladder wall. Can also be used to invade the wall and multiply then bursts out
What inhibits bacteria growth in the urinary tract?
Extremes of osmolarity, low pH and high urea concentration inhibit bacterial growth
Urine flow flushes bacteria out
Inflammatory response
What are the different areas in the lower urinary tract that can get infected?
Urethritis, prostatitis, epididymo-orchitis, cystisis (bladder), and pyleonephritis
What is the clinical presentation of pyelonephritis?
Loin pain/ flank tenderness, fever, rigors, sepsis
What are the clinical features of cystitis?
Dysuria, frequency urgency, suprapubic tenderness
What symptoms can be seen in infants (<2 years) and the eldery with a UTI?
Infants= vomiting/fever
Elderly= confusion/ falls
What are the differential diagnosis of dysuria in adults?
Dermatologic (dermatitis)
Infectious
Foreign body
Urethritis
Urethral structure abnormality
Drug related
Cancers
The prescence of what in a urine dipstick test indicates a possible UTI?
Nitrates
What age should urine dipstick tests be used for UTIs and why?
Only to be used in patients < 65
Presence of an infection in older people does not necessary mean UTI. Less efficient muscles flush out bacteria less efficiently and this causes 50% of people to have colonised bacteria
What is important when gathering a urine sample?
Mid stream sample
What is the difference between symptomatic and asymptomatic bacteruria?
Asymptomatic= significant bacteriuria in a patient without symptoms. Only treated in pregnant women
Symptomatic bacteruria= UTI
What are the different urine cultures that can be done?
Flexicult= for primary care, rapid result for UTI
Molecular markers= check for bacteria, inflammation (more likely to have UTI with the two) and presence of antimicrobial resistance
What are useful antibiotic guidelines?
Scottish antimicrobial prescribing group website
What antibiotics are used usually for cystitis?
If there is no risk factors for trimethoprim (e.g. in a nursing home, taken them before) use trimethoprim
If there is risk factors and eGFR > 30 use nitrofurantoin
What are antibiotics for in cystitis?
Makes symptoms better and shorterns them- not necessary for cure
What can antimicrobial use increase the likelihood of in UTIs?
Increases risk of recurrent UTIs
Increases risk of antimicrobial resistance
What antibiotic should not be given to patients with pyelonephritis?
Nitrofurantoin- does not reach therapeutic concentrations in the upper urinary tract
What is the treatment for an upper UTI?
Gentamicin, consider adding amoxicillin
If have a penecillin allergy, consider adding vancomycin
Why do you not use a urine dipstick test to diagnose catheter associated UTIs?
Urine culture is often positive in those with a catheter
CAUTI is diagnosed clinically
How are catheter associated UTIs treated?
Secondary care- gentamicin, large singular dose and change catheter
Primary- treat as a lower UTI
What is important to consider while treating pregnant women for UTIs?
Avoid contra-indicated antibiotics
What is a common reason for kidney failure that children with a UTI might have?
Vesico-uteric reflux- urine moving back into the kidneys
What simple advice should be given for patients with recurrent UTIs?
High fluid intake, avoid fizzy frinks and alcohol
Post coital voiding and lubrication for intercourse
Hygeine- wiping front to back
Avoid perfumed products
Smoking cessation, consider weight reduction
What treatment options can be considered in patients with continued recurrent infections?
For post menopause women- topical vaginal oestrogen
Post coital antibiotics- trimethopin once or self start antibiotics after symptoms (still need urine culture)
Trial of methenamine with Vit C
How does methenamine with vit C help with UTIs?
Non-micriobial treatment- makes urine full of formaldehyde and vit c makes it more acidic
Harder for bacteria to grow
