Red Book - Fungal Infections Flashcards
Why is fungal infection important in ICU
Incidence is rising
More immunusuppresed patients (cancer, chemo, HIV)
Increasing use of invasive devices Use of broad spec abx Increasingly aggressive medical/surgical intervention
What is an invasive fungal infection
Disseminated or invasive fungal infection in the presence of fungus in the blood.
OR
A deep seated infection due to haematogenous spread
Term distinguishes systemic infection from colonisation of a non-sterile site with no infection or superfiical infection (dermatitis, oesaphagitis)
Important ICU fungal pathogens
Candida is 6th most common pathogen in ICU
C.albicans accounts for 50% of fungal infections
Non albicans acound for majority of the rest
non albicans is rising due to increased fluconazole
Aspergilus rising and represent 15%
Risks for fungal infection
ICU admission has high rate of fungal colonization/transmission
High APACHE score
Co-morbidities - COPD in particular
AKI with RRT
Immunosuppr
Broad spec Abx use
PN
Vascular/urinary catheters
Surgery - abdo, perforated viscous
Colonisation of many sites
Criteria to diagnoise fungal infection
Defnitive or suggestive
Definiitve: Single positive BC - never mistake for contaminant Positive culture from biopsy spec Endopathalmitis Burn wound invastion Positgive culture of CSF or ascites
Invasive infection suggested by presence of three colonised sites
What would increases suspicioun of disseminated fungal infection in ICU
Immunocomp - may have no signs
Non-specific inflammatory response
Evidence of organ dysfunction
Consider fungal treatment if:
Persistent fever despite Abx and negative micro High grade finguria in UNCATHETERISED pt Funguria persisting AFTER catheter out Fungus cultured at >2 sites Visceral fungal lesions
How to investigate
Blood cultures (usually only pos half the time)
Retinal exam
Catehter urine for MC&S
Echo - endocarditis
Biopsies of tissues
Management
Start antifungal cover immediately if suspected, do not wait for micro
Candida isolate:
Often found in resp secretions, but true LRTI is rare
Therefore should not prompt treatment
Asymptomatic candiduria:
Change catheter
Treat if persists, or high risk pts
Candidaemia
Change line, send tip for MC&S
Non neutropenic - line removal improves outcomes
If difficul access ?re-wire, send old tip
Prognosis of candidaemia
Mortality og 40-60%
What is aspergillus
Spore forming moulds in soil
Only a few types are harmful
Aspergillus fumigatus Aspergillus niger
Commonest site of infection is lung
How does aspergillus pneumonia present
Non specific
Fever, cough, dyspnoea, pleuritc pain, hamoptysis
Micro diagnosis is difficult
PCR for fungal DNA
Galactomannan
Beta D glycan (cell wall)
Types of antifungal
Polyenes —> Amphotericin B
Azoles - Flucon, itracon, voricon
Echinicandins - caspofungin
Treatment of candidiasis
Fluconazole
non albicans may resist
Amphoetricin
Treatment of aspergillus
Vooriconazole / amphotericin (or both)
Tx Cryptococcus
Amphotericin
Fluctosine
