Fungal Infections Flashcards
who does fungal pathogens mainly effect?
imapired immune system, chronic lung diseases, ICU patients.
how do you get Candidisis?
abx use, inhaled steroids, moist areas, neonates<3mo.
sy of primary immunodefiiciency disorers…
Neutropenia, Low CD4+ T-cells, impaired IL-17 immunity
invasive candidiasis?
Gut commensal, Infections mostly endogenous of origin Clinical presentation as bacterial BSI, Mortality up to 40%, Additional risk-factors: Broad-spectrum antibiotics, Intravascular catheters, Total parenteral nutrition, Abdominal surgery
how is invasive candidiasis diagnosed?
blood culture, PCR
how is aspergillus transmitted?
sporulation, hydrophobic conidia, airbourne, inhalation.
types of pulmonary aspergillosis…
acute invasive,
chronic,
allergic
outline acute invasive pulmonary aspergillosis
Neutropenic host, Rapid and extensive hyphal growth, Thrombosis and hemorrhage, Angio-invasive and dissemination, Absent or non-specific clinical signs and symptoms, Persistent febrile neutropenia despite broad-spectrum antibiotics, Mortality rates around 50% (but depending on immune recovery)
how to diagnose non-neutropenic pateints with aspergillosis
Cultures of sputum and/or bronchoalveolarlavage, and/or biopsy, Aspergillusspecific IgG and IgEin chronic and allergic pulmonary aspergillosis
how to diagnose neutropenic patients with aspergillosis
High resolution CT-chest, ‘halo-sign’ and ‘air-crescent sign’, Molecular markers in blood: galactomannan and PCR-Aspergillus(high NPV and are suited for screening purposes), BAL and biopsies if clinical condition allows
what is cryptococcus?
Transmission by inhalation, can be found on the bark of a variety of trees, bird faeces and organic matter, Pulmonary infection from asymptomatic to pneumonia, Dissemination to brain: meningoencephalitis in HIV/AIDS patients (CD4 < 100 cells/ul), Clinical presentation: headache, confusion, altered behaviour, visual disturbances, coma (due to raised intracranial pressure in 60-80%)
how can you diagnose crypto coccus?
CSF: indian ink preparation, culture, high protein and low glucose. Blood culture.
name antifungals (and how they work)
Amphotericin B formulations (iv) = Acting on ergosterol> lysis BROADEST ANTIFUNGAL ACTIVITY
Azoles (iv, oral) = Inhibiting ergosterolsynthesis
Echinocandins(iv) = Inhibiting glucan synthesis
Flucytosine(iv, oral) = Inhibiting fungal DNA synthesis
tx invasive candidiasis
Echinocandins and fluconazole
tx invasive aspergillosis
Voriconazole and Isavuconazole
