301 Urinary incontinence and UTIs Flashcards
What is nocturnal enuresis?
Involuntary urination happens at night while sleeping, after age when person should be able to control his or her bladder
What is urinary incontinence?
Urinary incontinence (UI) also known as involuntary urination is any uncontrolled leakage of urine
Sensation of full bladder does not wake child
What is nocturnal enuresis caused by?
Caused by over production of urine at night, exceeding capacity of bladder to hold
Causes of bedwetting
Insufficient secretion of antidiuretic hormone (ADH) at night
Bladder dysfunction
Impaired brain arousal
Vasopressin mechanism:
Stimuli for Vasopressin Release
Release Site
Effects of Vasopressin
Overall Effect
- Hyperosmolarity, angiotensin II, decreased atrial receptor firing & sympathetic stimulation
- Posterior Pituitary
- V₁ Receptors (Blood Vessels): Constriction → Increased Systemic Vascular Resistance, V₂ Receptors (Kidneys): Fluid reabsorption → Increased Blood Volume
- Increased Arterial Pressure
ADH hormone (vasopressin) released by and acts on?
Pituitary gland
Acts on V2 receptors in distal kidney tubule to increase water reabsorption
Diabetes insipidus
ADH is reduced or absent, lack of sensitivity, leading to production of large volumes of dilute urine
Risk factors of bedwetting
Bedwetting family history
Male gender (2:1 male to female ratio)
Delay in attaining bladder control
Obesity
Psychological/behavioural disorders, such as ADHD, autism spectrum disorder & anxiety, depressive & conduct disorders
Underlying causes of bedwetting
Constipation
Diabetes
UTIs - if symptoms are recent
Behavioural or emotional problems
Family problems
Types of bedwetting
- Primary bedwetting without daytime symptoms - re-assure & provide non-pharmacological/pharmacological management
- Primary bedwetting with daytime symptoms - refer to specialist teams
- Secondary bedwetting - identify underlying cause, especially if child has been dry at night for 6 months
What is desmopressin?
Analogue of ADH and selective to V2 receptors in kidneys
How does desmopressin work?
Reduces amount of urine body produces at night; this mimics action of body’s own naturally occurring ADH
Management of nocturnal enuresis
Avoid blame and reassure parents
Bedwetting common in children under 5
Give advice on:
Diet and fluid intake
Toileting patterns
Lifting and waking
Positive reward systems
Enuresis alarms
1st line
High long-term success rate
Recommended for children 7+
Can be used younger but based on maturity & motivation
Desmopressin onset and short term improvement
Provides rapid onset in improvement or when short-term improvement is required
Start low & titrate up on response
Continue 3 months then stop for 1 week to check dryness
What should be cautioned with desmopressin?
Due to fluid retention, reduce fluid intake as blood becomes dilute and can cause hyponatraemia
Reduce fluids 1 hour before medication and 8 hours after
Patient and carer advice for desmopressin and hyponatraemic convulsions
Patients being treated for primary nocturnal enuresis should be warned to avoid fluid overload (including during swimming)
Stop taking desmopressin during an episode of vomiting or diarrhoea (until fluid balance normal)
* Patients being treated for primary nocturnal enuresis should be warned to avoid fluid overload (including during swimming)
Stop taking desmopressin during an episode of vomiting or diarrhoea (until fluid balance normal)
Imipramine
TCA
Last-line and used only when everything else failed
How does imipramine work?
Combination of increasing bladder activity (anticholinergic effects), improving arousal from sleep and enhancing bladder sphincter control (smooth muscle tone)
When should you consider imipramine?
Children and young people with bedwetting who have not responded to all other treatments & have been assessed by healthcare professional with expertise in management of bedwetting that has not responded to alarm and/or desmopressin
Why is imipramine and antimuscarinics often discontinued?
Side effects
Role of autonomic NS on bladder control
Parasympathetic - contract bladder
Sympathetic - relax bladder
Bladder control mechanism:
Bladder muscle (detrusor)
Bladder neck
- M₃ Receptors (Cholinergic - ACh): Contraction
β₃ Receptors (Adrenergic - NA): Relaxation - M₃ Receptors (Cholinergic - ACh): Relaxation
α₁L Receptors (Adrenergic - NA): Contraction
Types of incontinence:
Stress urinary
Result of weakening/damage to muscles used to prevent urination, such as pelvic floor muscles & urethral sphincter, when physical activity or movement puts pressure on bladder
Types of incontinence:
Urgency urinary
Result of overactivity of detrusor muscles, controls bladder resulting in intense, sudden urge to urinate, associated with overactive bladder syndrome
Types of incontinence:
Mixed urinary
Combination of both stress and urge of incontinence which results in patients experiencing symptoms of both types
Types of incontinence:
Overflow
Caused by obstruction or blockage in bladder, preventing it from emptying fully
Drug induced incontinence
Alpha-1, adrenoceptor antagonists (alfuzosin, doxazosin, tamsulosin)
Antipsychotics (chlorpromazine & haloperidol)
Anticholinergics - (causes retention so can cause ‘overflow’)
Anti-parkinsonism drugs
Antidepressants
BZDs
Beta blockers
Diuretics
HRT
Urinary incontinence management in women
Reduce caffeine intake
Fluid intake - avoid drinking excessive or reduced amount of fluid each day
Weight loss, especially if BMI is 30kg/m2 or greater
Smoking cessation
Supervised pelvic floor muscle training - especially after pregnancy
Surgery
Medication
Choice of medication for urinary incontinence in women
Antimuscarinics
Mirabegron
Duloxetine
Desmopressin (Nocturia)
When are antimuscarinics recommended in incontinence?
Recommended for urge incontinence and overactive bladder syndrome (OAB)
Low acquisition cost antimuscarinic drugs for incontinence
Oxybutynin (immediate release)
Tolterodine (immediate release)
Or darifenacin (once daily preparation) can be used for 1st line
What to offer women with incontinence when unable to tolerate oral antimuscarinics?
Offer a transdermal OAB drug to women unable to tolerate oral medication
Side effects of antimuscarinics
Dry mouth (high in oxybutynin IR)
Dry eyes, constipation, blurred vision
Reduced cognitive function (oxybutynin reduces, while trospium does not cross BBB)
Avoid close-angle glaucoma
QT prolongation (high oxybutynin, sometimes tolterodine, none trospium but studies only in healthy adults)
Antimuscarinic load e.g. amitriptyline
Diagnosis of dementia
What do adrenergic receptors do and why do they have a role in OAB treatment?
Stimulation of beta receptors leads to activation of adenylyl cyclase to release cAMP and inhibition of detrusor muscle
Beta3-receptors are present in bladder wall and beta 3 agonists have a role in OAB
Mirabegron and OAB
Recommended as 2nd line treatment for patients who cannot tolerate antimuscarinics or have minimal benefits from these meds
Mirabegron cautions in OAB patients
QT interval prolongation history
Bladder outflow obstruction
Patients taking CYP3A4 inhibiting drugs
Renal impairment
Hepatic impairment
What type of agonist is mirbegron?
Beta 3
Mirabegron and drug safety
Mirabegron is now contraindicated in patients with severe uncontrolled hypertension (systolic BP >80mmHg and diastolic >110mmHg or both)
Regular monitoring of BP important, especially in patients with pre-existing hypertension
What is duloxetine used for?
Pharmacological treatment recommended for stress UI
How does duloxetine work?
Selective inhibitor of 5-HT and NE receptor sites and works centrally to activate pudendal nerve which facilitates the sphincter activity during urine storage but not during voiding
Stronger closure of urethra during urine storage which may explain efficacy in SIU as physical stress induced
When should duloxetine not be used?
1st line for omen with predominant stress UI, can offer duloxetine as 2nd line for women with stress UI but only if they prefer drug treatment instead of surgery
Why is duloxetine failed for SUI in US approval?
Due to liver toxicity and suicidal events
UTI prevalence
More common in women (50% at some stage) but more serious in men (complicated UTIs)
Types of UTIs: lower UTI
Cystitis common bladder infection caused by bacteria from GI entering urethra
Types of UTIs: they can be…
- Uncomplicated is UTI form affecting healthy individual with structurally & functionally normal urinary tract
- Complicated UTIs occur in individuals with anatomical, functional or medical conditions increase infection risk or complicate treatment
Types of UTIs: upper UTI
An infection of upper part of urinary tract (ureters & kidneys) - pyelonephritis
Types of UTIs: recurrent UTI
2 or more episodes of UTI in 6 months or 3 or more episodes in 1 year
Types of UTIs: catheter-associated UTI
Women with a catheter in situ within previous 48 hours
UTIs and bacteriuria
Presence of bacteria in urine with patient being/or not being symptomatic
Uncomplicated symptoms of UTIs
- Dysuria - discomfort, pain, burning, tingling or stinging with urination
- New nocturia - waking at night >1 times to pass urine
- Cloudy urine to naked eye
- Urgency/frequency
Complicated symptoms of UTIs
- Kidney pain/tenderness in back under ribs
- New/different myalgia, flu like illness
- Shaking chills (rigor) or temp >37.9
- N + V
UTI: urinalysis results
pH
Blood
Nitrites
Leukocyte esterase
- Represent urine acidity - raised in UTI
- Amount of RBCs, Hb & myoglobin in urine - positive for blood in UTI
- Breakdown product of G- organisms like E.Coli - positive for nitrites in UTI
- Enzyme produced by neutrophils indicate WBC presence in urine - positive for leukocyte esterase in UTI
UTI complications
- Acute or chronic pyelonephritis
- Renal or peri renal abscess
- Pyonephrosis
- AKI or CKD
Urosepsis - Increased risk of pre-term delivery or low birth weight
- Reduced QoL
Uncomplicated UTI treatment
1st: treat according to culture sensitivity
Nitrofurantoin 100mg MR BD for 3 days OR if low risk of resistance trimethoprim 200mg BD for 3 days
2nd: if no improved symptoms for 48 hours or C/Is
Nitrofurantoin 100mg MR BD for 3 days (if not 1st)
Pivmecilliam 400mg STAT, then 200mg TDS for 3 days
Fosfomycin 3g single dose sachet
What changes from uncomplicated to complicated UTI treatment?
Length increases to 7 days
UTI in pregnancy
Complications of UTI to infant, consider when managing
Perform mid-stream urine (MSU) for culture and sensitivity before antibiotic treatment
Repeat C&S when antibiotic complete
UTI in pregnancy treatment depending on culture & sensitivity
- Cefalexin 500mg TDS for 7 days
- Amoxicillin 500mg TDS for 7 days
- Nitrofurantoin 100mg MR BD for 7 days (avoid 3rd tri)
- Trimethoprim 200mg BD for 7 days (avoid in 1st tri)
ESBLs (extended-spectrum beta-lactamases)
- Resistant to many penicillin & cephalosporin antibiotics
- 2 main bacteria that produce ESBLs are E.coli & Klebsiella species
- ESBLs E.coli produce most often are CTX-M enzymes
- E.coli with ESBLs may cause UTIs which progress to blood poisoning, can be life-threatening
UTIs: E.coli & B-lactam antibiotics
E.coli most common organism degrade B-lactams with extended spectrum (such as 3rd generation cephalosporins)
UTI: resistance agents
- If UTI resistant to trimethoprim, nitrofurantoin & amoxicillin then after C&S pivmecillinam 400mg STAT then 200mg TDS
- For ESBL producing organisms, pivmecillinam 400g TDS for 7 days (a penicillin but low C.diff risk) or fosfomycin 3g granules (hospital outpatients)
Recurrent UTIs (non-pregnant)
Rule out RED flags if haematuria present
Choice is single dose antibiotic after exposure to trigger or low-dose daily antibiotic as prophylaxis
Recurrent UTIs (non-pregnant) treatment
- Trimethoprim 100mg nocte or nitrofurantoin 50-100mg nocte for 6 months then review, soe rotate to avoid resistance but evidence weak
- Or amoxicillin 250mg at night (off-label indication) or cefalexin 125mg at night
- Provide self-care advice
- Cranberry product limited evidence - not NICE recommended & interacts with warfarin
UTI: self-care advice
- Analgesia (paracetamol, NSAIDs)
- Adequate fluid intake
- Don’t recommend OTC cranberry products or urine-alkalising products
- Avoid alcohol, fizzy drinks & caffeine
- Wipe front to back (bacteria spread)
- Urinate after sex
- Vaginal douches & washes - be careful
UTI: catheter patients
- Avoid Foley catheters if possible
Catheters usually colonise large no. of bacteria - Dipstick always positive
- Treat with Abx when symptomatic e.g. fever & dysuria, not if asymptomatic
UTI: pathogenesis of UTI
1. Colonisation
2. Uroepithelium penetration
3. Ascension
- Pathogen colonises periuretheral area & ascends through urethra upwards towards bladder
- Fimbria allow bladder epithelial cell attachment & penetration, following penetration bacteria continue to replicate & form biofilms
- Once sufficient bacteria colonisation, bacteria ascend on ureter towards kidney, fimbria aid ascension, bacterial toxins play role by inhibiting peristalsis (reduced urine flow)
UTI: pathogenesis of UTI
4. Pyelonephritis
5. AKI
- Infection of renal parenchyma causes pyelonephritis, while infection of renal parenchyma usually result of bacterial ascension, can occur from haematogenous spread
- If inflammatory cascade continues, tubular obstruction & damage occur, leading to interstitial oedema, may lead to interstitial nephritis causing AKI
UTI: pyelonephritis - acute
Caused by E.coli
Symptoms: flank/renal angle pain, myalgia, flu-like symptoms, rigors or raised temp, N + V
Complications: sepsis, renal scarring, recurrent UTIs, renal abscess, pre-term labour in pregnancy, emphysematous pyelonephritis
UTI: acute pyelonephritis treatment
Refer to specialist for high risk groups (pregnant, recurrent infection), rule out sepsis, MSU
- Cefalexin 500mg BD or TDS for 7-10 days
- Co-amoxiclav 500/125mg TDS for 7-10 days
- Trimethoprim 200mg BD for 14 days
- Ciprofloxacin 500mg BD for 7 days - only when other antibiotics inappropriate
