wk 9- skin and nail infections Flashcards
types of antibiotic therapy
directed
empirical
prophylactic
bacterial infection that has green colouration to is is caused by what organism
pseudomonas infection
infection with white/creamy pus is typically what bacterial infection
streptococcus infection
if pus is golden, runny and straw coloured then its likely what bacterial infection
staphloccocus infection
vesticular bullous tinea pedis is caused by what fungal infection
trichophyton rubrum and
trichophyton mentagrophytes
chronic hypertrophic appearance with dusty scale like nail is caused by what fungal infection
moccasin tinea pedis
whos at risk of fungal infection
older people
diabetes
pregnant women
biologics - immunosuppressant
fungal infections can be caused by
dermatophytes and yeasts, different treatment for these organisms
why to treat tinea pedis
- comfort- itching, scaling, etc
- appearance/cosmetic
- secondary infections, especially in those who are at risk/immunocompromised
dermatophytes
What can it infect
What types of
can infect skin, har, nails
tinea pedis is what we’re interested in
most common:
1. trichophyton rubrum
2. trichophyton interdidigitale
3. epidermophyton floccosum
yeast
What can it infect
Most common species
candidiasis (candida albicans) most common species
can infect
1. mucuous membranes,
2. nails (paronchyia),
3. skin (skin fold, chronic paronchyia)
clinical features of tinea pedis
hyperkertotic- patchy, fine dry scaling on sole of foot
maceration in webspace
clusters of blisters/pustules on side of feet
round patches on top of foot
predisposing factors of tinea pedis
- exposure to spores (environment)
- lower production of fatty acid
- occlusive footwear
- not changing socks/shoes
- excessive sweating
- immunodeficiency
- poor ciruclation
non pharmacological advice to manage tinea pedis
dry feet
wear shoes in communal areas
wash socks/jocks at a high heat
dry clothes in sun, UV light kills
moisture/cotton socks
onychomycosis caused by what pathogens and what species
dermatophytes (tinea unguium)
often occurs from untreated tinea pedis
can be caused by yeast- candida albicans
and moulds
if you have onychomyosis what happens with tinea pedis
recurring issue
constant secondary infections
types of onychomyosis
- distal OM
- lateral OM
- subungal onychomycosis
- superficial white onychomycosis
- total dystrophic onychomycosis
- proximal subungal OM
Chronic paronychia v acute
inflammation of the nail fold that can be caused by yeast/moulds
acute is caused by bacteria
different presentations.
acute has more inflammation/pus
do you need to confirm tinea pedis
no
if youre going to prescribe oral therapy should you confirm diagnosis
yes
where to take samples from
leading edge of the lesion after cleaning- tinea pedis
as proximal as possible - OM
microscopy and culture
M- comes back quickly
C- can take weeks
high false negative rate up to 40%
topical treatment for tinea pedis
- terbinafine 1% cream/gel applied once or twice daily for 1-2weeks
-fungicidal - azoles applied twice daily for 2-4 weeks
-fungistatic
oral treatment for tinea pedis
- terbinafine 250mg, once daily 2 weeks
- fluconazole 150mg, once daily 6 weeks
- itraconazole 100mg once daily 4 weeks
- griseofulvin 500mg, once daily for 8-12 weeks
what doesnt get recommended in AMH for OM
topical therapy
success rate is around 8% and costs are around 70% for a bottle or more
oral treatment for OM
1.terbinafine 250mg once daily until clearance
- fluconazole 150-300mg once weekly until clearance
- itraconazole 100-200mg twice daily for 1 week every month until clearance
- griseofulvin 500-1000mg once daily until clearance
comparison of azoles and griseofulvin
similar effectiveness but griseofulvin is longer treatment and more side effects
other options for OM
- laser - UV rays/heat to destroy
- photodynamic - “
- iontophoresis delivery - electric charge to drive topical medications deeper into the nail plate
OR
drill holes into nail plate to get topicals to the nail plate - surgery- avulsion apply topical treatment
what is onycholysis
nail separation
treatment for onycholysis
if candida confirmed
1. fluconazole 150-300mg once weekly for 3 months / clearance
- intaconazole 200mg, twice daily for 1 week every month for a total of 3 months or until clearance
if pseudomoas confirmed
1. acetic acid / vinegar soak the nails for 5-10min twice daily for 3-4 weeks
what do you need to consider with topical therapy
can they reach feet
compliance?
what to consider with oral therapy
-interactions?
-ADRs
-compliance
-dose adjustments?
-renal/ hepatic impairments?
-success rate
what needs to be done when terbinafine is started
baseline blood test of
renal function
full blood count
liver function
follow up tests every 6 weeks
commonside effects of terbinafine
headache
muscle aches (myalgia)
joint pain
nausea
griseofulvin important notes
lots of side effects
suspected teratogen- contraindicated in pregnancy or wanting to become pregnant (1 month before) OR 6 months to prospective fathers
fluconazole itraconazole
oral form- pods cant prescribe not on formulary
what needs to be done when starting oral therapy for infection
shared decision making with GP and ensure systemic symptoms are monitored by GP
what does M and C do
-diagnose pathogen
-show the virulence (how fast its growing)
-what antibiotics can treat it (resistant/susceptible)
if you’ve send off for a M and C after empirical didn’t work what do you need to do
state what antibiotic has been used as it will change the way the pathogen grows
Review antibiotics
-types
-MOA
-considerations
-cidal/static
treating infections stpes
- wound swab and send for M and C
- have an idea what pathogen we suspected based off symptoms and nature
- empiracal therapy based off EBP
- within 48-72 hours review progress and make changes if required (stop, continue, change therapy)
what is the difference between oral and IV/IM antibiotics
first pass effect/bioavailability
-it can be faster acting via IV/IM
-It isnt stronger
when to use IV antibiotics
depends on the risk of sepsis or complications
thinks to think about when prescribing antibiotics
ADRs
interactions
resistance
dose adjustments
route
with/without food
what EBP to use for empiracal therapy
therapeutic guidelines
when would people use prophylatic antibiotics
orthopaedic surgry when theres a strong risk of a problematic infection (into a joint)
what pathogen causes acute paronychia
staphloccocus pyogenes
what is non therapeutic treatment of acute paronychia
drainage
antibiotic therapy of acute paronychia
that doesnt respond to drainage
- dicloxacillin
- flucloxacillin
6hourly for 5 days
in the case of a delayed nonsevere penicillin allergy
- cefafexin 12 hourly 5 days
in the case of a immediate nonsevere/severe or delayed severe penicillin allergy
- clindamycin 8 hourly 5 days
impetigo is
highly contagious
treatment for impetigo
topical: mupirocin (bactroban) 2%
if theres extensive involvement or recurrence then oral antibiotic therapy instead
what therapy can be used on minor superficial infected wounds
povodine iodine antiseptics
pitted keratolysis
bacterial infection affecting plantar skin
white, cater like lesions
associated with hyperhidrosis which should be managed
therapy for pitted keratolysis
clindamycin twice daily for 10 days
in conjunction with hygiene, reducing hypehidrosis etc
transgradient means
affecting multiple borders of the foot
eg redness aruond heel, dorsum, lateral , medial , plantar aspects
types of tinea
tinea vesticular bullus
tinea interdigitale
