UTI in practice Flashcards
2 parts of the lower urinary tract
bladder
urethra
Where can a UTI affect?
any part of the urinary system
- kidneys, ureters, bladder, urethra
typical bacteria that cause UTI
E coli (Gram negative)
How do bacteria enter the GIT?
through the urethra
symptoms of bladder UTI (cystitis)
polyuria
dysuria
lower abdominal discomfort
symptoms of urethra UTI (urethritis)
burning on passing urine
discharge
risk factors for UTI
- females (shorter urethra, urethra proximity to anus)
- post menopausal women (dec oestrogen)
- catheters (route for bacteria)
- recent antibiotics (disrupts normal bacteria)
- spermicides (irritation and attachment sites for E. Coli)
- sexual intercourse (bacteria to UT)
- pregnancy (progesterone stimulates SM relaxation to bladder and uterus and compression of ureters by uterus)
when to refer UTI
- pregnancy
- men
- < 16yrs
- symptoms of pyelonephritis
- signs of sepsis
- non respondant to first antibiotics
risks for UTI in pregnancy
pyelonephritis
premature birth
rupture of membranes
symptoms of pyelonephritis (upper UTI)
fever loin pain (kidney pain/tenderness in back under ribs) rigors (temp rises quickly)/ pyrexia flu-like illness/myalgia nausea/vomiting
What is pyelonephritis?
upper UTI
high risk signs of sepsis
altered mental state/behaviour increased RR/HR low BP anuria (not passing urine) mottled/ashen (grey) skin cyanosis (blue skin/lips) non-blanching rash (doesn't go with pressure)
When is urine dipstick not recommended and why?
elderly (>65yrs)
asymptomatic bacteriuria is common in elderly and could result in unnecessary antibiotics
When is urine culture not necessary?
if uncomplicated first UTI in women
What to do if urine culture done and bacteria is resistant?
amend antibiotics (if still symptomatic)
When not to treat a UTI?
if it’s asymptomatic (unless pregnant)
What causes need to be excluded before diagnosis?
vaginal and urethral causes
- urethritis: post sexual intercourse, irritants
- sexual Hx to exclude STI
- genitourinary syndrome of menopause
3 key signs of UTI
dysuria
new nocturia
cloudy urine
When is dipstick not needed (UTI likely)?
2 or 3 symptoms present
dysuria, nocturia, cloudy urine
When to perform dipstick?
1 symptom present
What to check if no symptoms are present?
urgency visible haematuria frequency suprapubic tenderness -> yes to these then dipstisk -> no, UTI unlikely
urine dipstick negative for nitrites, leukocytes, RBC
UTI less likely
urine dipstick negative for nitrates but positive for leukocytes
could be UTI
send urine culture and consider treatment depending on symptom severity
urine dipstick positive for RBC, positive nitrite/leukocyte
likely UTI
treat or watch/wait with backup antibiotic depending on symptom severity
difference in treatment for over 65
- no urine dipsticks
- new onset dysuria or 2+ new symptoms UTI likely
- always send urine culture
- delirium considerations/other diagnostics
When are antibiotics given for UTI in pregnancy?
bacteriuria confirmed even if symptomatic
treatment for suspected UTI in pregnancy
- paracetamol for symptomatic relief
- prescribe antibiotic 7 days (often nitrofurantion, not at term)
- MSU for culture
- amend prescription if needed
MSU
midstream specimen of urine
group B streptococcus isolated in pregnant woman
prophylactic antibiotics offered during labour and delivery
-> risk to baby
Why are antibiotics given if asymptomatic UTI in pregnancy?
pyelonephritis and premature delivery risk
What to consider before giving antibiotics?
how severe the symptoms are
risk of complications
previous urine culture results
previous antibiotic use
When are back up antibiotics used?
if no improvement after 48hrs or symptoms worsen at any time
Who have a low risk factor for antibiotic resistance?
younger women with acute UTI and no resistance risks
risk factors for increased resistance
- care home resident
- recurring UTI (2 in 6mths, >3 in 12mths)
- unresolving symptoms
- hospitalisation for >7d in last 6mths
- recent travel to a country with inc resistance
- pevious UTI resistant to trimetoprim/cephalosporins/
quinolones
What antibiotics can increase clostridium difficile infections?
ciprofloxacin
cephalosporins
co-amoxiclav
(3 Cs)
What antibiotics should be used for UTIs to reduce clostridium difficile?
nitrofurantoin
trimethoprim
pivmecillinam
When should co-amoxiclav only be used?
- pyelonephritis in pregnancy
- facial cellulitis or prophylaxis post dog/human bites
- diverticulitis
- persistent sinusitis 2nd line
trimethoprim (spectrum/resistance)
narrow spectrum
resistance is common
nitrofurantoin (spectrum/resistance)
broad spectrum
concenctated in the area of need
resistance rates are lower
recommended treatment for most uncomplicated UTIs
3 day course of empirical antibiotics
How effective is a 3 day course of empirical antibiotics for uncomplicated UTI?
- more effective than single doses
- as effective as 5-10 day course
1st line choice for UTI O16, not pregnant
nitrofurantoin 100mg MR BD for 3 days
- if eGFR > 45
1st line choice UTI O16, not pregnant (after nitrofurantoin)
trimethoprim 200mg BD for 3 days
- if low risk resistance
FIRST 2nd line UTI O16, not pregnant
-> when no improvement in symptoms on 1st line after 48hrs OR 1st line not suitable
nitrofurantion 100mg MR BD for 3 days
- eGFR >45 and not 1st choice
SECOND 2nd line UTI O16, not pregnant
-> when no improvement in symptoms on 1st line after 48hrs OR 1st line not suitable
pivmecillinam 400mg initial dose
then 200mg TDS for 3 days
THIRD 2nd line UTI O16, not pregnant
-> when no improvement in symptoms on 1st line after 48hrs OR 1st line not suitable
fosfomycin 3g single dose sachet
MOA of nitrofurantoin
- concentrated in urine
- bactericidial
- reduced by bacterial flavoproteins to reactive intermediates which inactivate/alter bacterial ribosomal proteins
nitrofurantoin and renal impairment
avoid if eGFR < 45
not effective in renal impairment as bacterial efficacy depends on renal secretion of drug into urinary tract
-> kidneys can’t concentrate it enough
When can you use nitrofurantoin in renal impairment?
can use 30-44ml/min in exceptional circumstances if benefits outweigh risks
How to take nitrofurantoin?
take with food to increase bioavailability
STD/MR nitrofurantoin dose
standard release 50mg QDS
MR 100mg BD (preferred, better adherance)
What can nitrofurantoin do to urine?
can darken urine - yellow/brown
contraindications of nitrofurantoin
eGFR low
G6PD deficiency
acute porphyria
infants < 3mths
nitrofurantoin cautions
liver toxicity pregnancy diabetes pulmonary disease anaemia low B12 folate deficiency
adverse effects of nitrofurantoin
- GI - nausea, vomiting, loss of appetite, diarrhoea
- dizzy/tired
- itchy rash/allergic reaction/swollen salivary glands
- peripheral neuropathy
- pulmonary reactions (breathing difficulty/chest pain)
How to minimise GI s/e of nitrofurantoin?
take with food or milk
When to discontinue nitrofurantoin?
- itchy rash/allergic rxn/swollen salivary glands
- peripharal neuropathy (pins and needlles etc.)
- pulmonary rxns (resp. problems)
-> unexplained pulmonary, hepatotoxic, haematological, neurological signs occur
What patients may be susceptible to peripheral neuropathy with nitrofurantoin?
diabetes (discontinue if signs)
MOA of trimethoprim
- inhibits DHFR which blocks reduction of dihydrofolate to tetrahydrofolate (the active form of folic acid) by susceptible organisms
- > ANTIFOLATE (not with methotrexate)
- inhibitory activity for most G+ aerobic cocci and some G- aerobic bacilli
dose of trimethoprim
200mg BD
trimethoprim and renal impairment
some dose reductions may be needed in severe renal impairment
interactions with trimethoprim
methotrexate
warfarin
can cause hyperkalaemia, caution with drugs that inc K (ACEIs)
contraindications with trimethoprim
blood dyscrasias
1st trimester pegnancy
adverse effects of trimethoprim
mild GI disturbance - n/v (mild, reversible)
pruritis and skin rash (mild, reversible)
blood disorders (long term)
self care for UTIs
- adequate fluid intake - flush bacteria from UT, avoid dehydration
- paracetamol for pain (or ibuproben)
- cranberry juice/tabs, alkalinising agents (no evidence)
- hygeine - wipe from front to back
- empty bladder after sex
- birth control (spermicides could inc. risk)
- avoid potentially irritating female products, can irritate urethra
What antiboitic can be supplied on PGD for UTI?
trimethoprim
PGD supply of trimethoprim for UTI
- pharmacist must have completed specific training before admin of the PGD
- record of supply made on patient’s PMR
- GP notified of supply
