Management of fungal infections Flashcards
fungal infections come from
fungal infections
antifungal agents
antifungal kill and stop growth of fungi
called antimyotic agents
Azole antifungals
- triazoles
- Imidazoles
Triazoles
- fluconazole; well absorbed (oral), good penetration into cerebrospinal fluid, excreted uncharged in urine and used to treat candiduria
- Itraconazole; active against dermatophytes, capsules an acid enviroment in stomach for optimal absorption, liver damage (associated)
(posaconazole + voriconazole)
Imidazoles
Clotrimazole, econazole nitrate, ketoconazole, and tioconazole - local treatment of vaginal candidiasis and for dermatophyte infections
Miconazole; ured locally for oral infections, effective in infections, systemic absorption may follow use of miconazole oral gel and may result in significant drug interactions
Polyene antifungals
- Amphotericin B
- Nystatin
Amphotericin B
- not absorbed when given by mouth
- intravenous infusion used for treatment of systemic fungal infections
- highly protein bound and penetrates poorly into body fluids and tissues
- given PARENTALLY amphotericin B is toxic into body fluids and side-effects are common
Lipid formulations are less toxic
- test dose is advisable before a new vourse of treatemnt
- small amount administred for 10 mins and stopped
Nystatin
Not absorbed when given by mouth
Used for oral, orpharyngeal, perioral infections by local application in mouth
used for candida albicans infection of skin
Echinocandin antifungals
Anidulafungin, caspofungin and micafungin
Only active agaist aspergillus and candida
andiulafungin and micafungin are not used for treatment of aspergillosis
echinocandins are not effective against fungal infections of CNS
Other antifungals
- Flucytosine
- Griseofluvin
- Terbinafine
Flucytosine
used with amphotericin B in synergistic combination
Bone marrow depression can occur which limits its use, paticularly with HIV-+ive patients, weekly blood counts are necessary during prolonged therapy
resistance to fluctosine can develop during therapy and sensitivity testing is essential before and during treatment
Griseofluvin
effective fro widespread or intractable dematophyte infections
superseded by newer antifungals, paticularly for nail infections
during therapy dependant on site of infection and may extend to number of months
terbinafine
drug of choice for fungal nail infections also used for ringworm infections where oral treatment is considered appropriate
Aspergillosis
Aspergillus species - found in soil
Inhalation of aerosolised spores causes infection
Affects immunocompromised patients
symptoms include; fever cough, pleuritic pain
1st line; Voriconazole = initially every 12 hrs for 2 doses, then 100mg every 12 hrs (inc if>40kg
2nd line; amphotericin B 3mg/kg OD
early diagnosis and therapy significantly imporve prognosis
Candidiasis
Candida > normal flora in GI and genitorinary tracts in humans, capable of loical infection of mucus membranes and also CNS infections
Oral and vaginal infection
Oral thrush
symptoms
refer?
treatment
symptoms:
can be asymptomatic, loss of taste or unpleasant taste, white patches and can be wiped off leaving behind red patches
refer if: symptoms NOT resolved after 7 days
person has pain swallowing
no obvious precipitant
poorly controlled diabetes
person with a single red/ white plaque that cannot be rubbed off
treatemnt; miconazole
nystatin oral suspension 100u/ml
counselling for oral thrush
maintain good dental hygiene
stop smoking
provide person with inhaler technique
Vaginal candiasis
common yeast infection, thrush
Caused by candida albicans
NOT an sti
if infection - parter may also need treatment
Vaginal candidiasis - management
managed with azole antifungals
1. topical vaginal cream
2. Pessary
3. Oral capsule
some oTC products avail. as mixture of formulations to treat infection and provide symptomatic relief
external Clotrimazole 2% cream (canesten)
used for immediate symptomatic relief of itch
apply thin layer to vulva and surounding area BD-TDS until symptoms disappear
common s.e = itching/burning sensation
can damage condoms
Internal clotreimazole 10% cream
administer intravaginally using applicator supplied
one-off treatment, best administred at night
side-effects; itching/ burning senstion
convenient but some women uncomfortable with formulation
can damage condoms
Pessary
500mg
200mg
100mg
s.e itching/ burning sensation
can damage condoms
oral capsule
fluconazole 150mg oral capsule
one-off dose, swollowed whole
take 12-24 hrs for symptoms tom improve
interactions: warfarin, statins, phenytoin, rifampicin, ciclosporin and theophylline
s.e = mild and transient; nsusea, abdo discomfort, flatulence and diarrhoea
Systemic candidasis
infection of blood or other normally sterile sites
incl. retina, kidney, liver and spleen adn CNS
symptoms; fever, trachycardia or tachypnoea
1st line; caspofugin
alternatively; fluconazole
2nd line; amphotericin B
Cryptococcosis
caused by cryptococcus species - found in bird
lungs are primarly affected
symptomatic involvement may occur in brain
symptoms - include pyrexia, productive cough, dyspnoea, chest pain, weight loss and fatigue
What are the treatment options for cryptococcosis?
flucanazole, itraconazole or amphotericin B
Cryptococcal meningitis
progressive, chronic
occurs in immunosuppressed individuals
symptoms; headache, severe headache, meningismus
Treatment for Cryptococcal meningitis?
amphotericin B by IV infusion and fluctosine by IV infusion for 2 weeks, fluconazole by mouth 8 weeks
Histoplasmosis
fungus proliferates - soil contaminated with bird or bat dropping
symptoms - fever, headache or dyspnoea
treatement - itraconazole
in severe infections: amphotericin B
histoplasmosis
fungus spreads to eyes
abnormal blood vessels - affect vision
care does not incl antifungal medications
fungus causes ocular histopolasmosis, not having a fungal infections
how are skin and nail infections treated
normally over counter
more severe scalp and nail
treated with POM
scalp - Tinea capitis (systemically); reduce transmission
oral griseofulvin
ketocanazole 2% shampoo
Nail
onychomycosis treated systemically
1st line terbinafine
2nd line itracinazole
Skin infections (fungal) list:
ringworm - spread perosn to person/ person to animal
ringworm of scalp
fungal nail infections - should b referred as system antibioticsn usually required
athlete’s foot - fungal food infection - person to person, contact of shared towels, changing rooms
Skin infections - treatment?
OTC topical antifungsal (ringworm)
Imidazoles e.g. micronazole cream (daktarin)
Itraconazole and terbinafine OTC in athelete’s foot treatment
Powder and spray formulations used fro athlete’s foot
refer?
treatment failure
bacterial infection
diabetic patients
involvment of nail
Commpn signs of fubgal skin infections
- folds of skin (not washed often, warm and damp)
- asymmetrical
- red, scaly advancing edge and clear central area
What are the differential diagnosis of ringworm?
eczema
pityriases
psoriasis
body and groin diagnossi of common fungal skin infections?
history of scaly, itchy skin
folds of skin
single or multiple red or pink, flat or slightly raised ring-shaped patches
treatment of fungal skin infections
topical antifungal cream (may need repeating)
mildy-potent corticosteroid, if there is inflammation (hydrcortisone 1% cream to be applied once daily for max 7 days
severe infection - Terbinafine 1st line
What to do with immunocompromised patients?
give them prophylaxis
