ID - 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.ORA deep seated infection due to haematogenous spreadTerm 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/transmissionHigh APACHE scoreCo-morbidities - COPD in particularAKI with RRTImmunosupprBroad spec Abx usePNVascular/urinary cathetersSurgery - abdo, perforated viscousColonisation 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 possible fungal infection?
Blood cultures (usually only pos half the time)Retinal examCatehter urine for MC&SEcho - endocarditisBiopsies of tissues
Management of invasive candidiasis
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 treatmentAsymptomatic 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 soilOnly a few types are harmful Aspergillus fumigatus Aspergillus nigerCommonest 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 BAzoles - Flucon, itracon, voriconEchinicandins - caspofungin
Treatment of candidiasis
Fluconazole| non albicans may resist Amphoetricin
Anti-fungal Treatment of aspergillus
Vooriconazole / amphotericin (or both)
Tx Cryptococcus
Amphotericin| Flucytosine
