Fungal infections Flashcards
Who gets fungal infections?
○ Patients with an impaired immune system
- Patients with primary immunodeficiencies
- Patients with HIV/AIDS
- Patients with malignancies (neutropenia) & transplants
- Premature neonates (immature immune system)
○ Affecting patients with chronic lung diseases (pulmonary aspergillosis and other moulds)
- Asthma
- Cystic Fibrosis
- Chronic obstructive lung disorders
○ Affecting patients in ICU settings
What is the aetiology of Mucocutaneus candidiasis?
○ Antibiotic use ○ Moist areas ○ Inhalation steroids ○ Neonates < 3 months ○ Presenting symptom of primary immunodeficiency
Which primary immunodeficiency disorders charecteristics can Mucocutaneuous candiditis be a presenting symptom of?
- Neutropenia
- Low CD4+ T-cells
- impaired IL-17 immunity
□ AD-Hyper IgE syndrome
® Deficit of IL-17 producing cells
□ Dectin-1 deficiency
® Reduced levels of IL-17
□ CARD9 deficiency
® Low proportion of circulating IL-17 T-cells
□ APECED syndrome
® High titers of neutralizing Ab against IL-17A, IL-17F and/or IL-22
What is the mortality of invasive canditis?
40%
Where does invasive canditis commune?
The gut
What are the additional risk factors for a invasive canditis infection?
- Broad-spectrum antibiotics
- Intravascular catheters
- Total parenteral nutrition
- Abdominal surgery
How is an invasive canditis infection diagnosed?
- Blood culture or culture from normally sterile site
- β-d-glucan high NPV and performs very well to exclude invasive candidiasis
- Recent developments in PCR assays very promising
- In infants and children performance lower due to sampling issues
How are Aspergillus and Aspergillosis transmitted?
- sporulation
- hydrophobic conidia
- diameter 2-3 µm
- airborne / inhalation
Who gets acute invasive pulmonary aspergillosis?
® Neutropenic patients (incidence 1-10%)
® Post transplants: stem cell > solid organ (incidence up to 8%)
® Patients with defects in phagocytes
What haens in acute invasive pulmonary aspergillosis?
® Rapid and extensive hyphal growth
® Thrombosis and haemorrhage
® 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)
Who gets (sub) acute Invasive Pulmonary Aspergillosis?
Non-neutropenic host (graft-versus-host disease, neutrophil disorders)
What happens in (sub) acute Invasive Pulmonary Aspergillosis?
® Non-angioinvasive ® Limited fungal growth ® Pyogranulomatous infiltrates ® Tissue necrosis ® Excessive inflammation ® Non-specific clinical signs and symptoms ® Mild to moderate systemic illness ® Mortality 20-50%
How long does one have to have pulmonary aspergillosis for it to be classified as chronic?
> 3 months
Who gets chronic pulmonary aspergillosis?
Patients with underlying chronic lung conditions
What happens in chronic pulmonary aspergillosis?
® Pulmonary exacerbations (not responding to antibiotics)
® Lung function decline
® Increased respiratory symptoms as cough, decreased exercise tolerance and dyspnoea
® Positive sputum cultures for Aspergillus
◊ 50% of CF patients are infected
® High morbidity but causative mortality rates less clear
