Infection Flashcards
What type of infections do neutrophils play a role in?
- Bacterial
- Fungal
What type of infections do monocytes play a role in?
Fungal
What type of infections do eosinophils play a role in?
Parasitic
What type of infections do T lymphocytes play a role in?
- Fugal
- Viral
- PJP
What type of infections do B lymphocytes play a role in?
Bacterial
What supportive factors are aimed at reducing sepsis in haematological malignancy?
- Prophylaxis
- Growth factors e.g. G-CSF
- Stem cell rescue/transplant
- Protective environment e.g. laminar flow rooms
- Intravenous immunoglobulin replacement
- Vaccination
What prophylaxis can help reduce sepsis in haematological malignancy?
- Antibiotics (ciprofloxacin)
- Anti-fungal (fluconazole or itraconazole)
- Anti-viral (aciclovir)
- PJP (co-trimoxazole)
What is the cause of neutropenia?
Marrow failure proves a higher risk than immune destruction
How is the degree of neutropenic risk classified?
Neutrophils
- <0.5x10^9 = significant risk
- <0.2x10^9= high risk
What duration of neutropenia carries a high risk?
- Neutropenic >7 days
- In AML therapy and stem cell transplantation there is profound neutropenia ~14-21 days
What are additional risk factors for infection?
- Disrupted skin / mucosal surfaces
- Hickman line, venflons
- Altered flora/ antibiotic resistance
- Prophylactic antibiotics
- Lymphopenia
- Disease process e.g. Lymphoma
- Treatment eg Fludarabine, ATG
- Stem cell transplantation, GVHD
- Monocytopenia
- Hairy cell leukaemia
- Chemotherapy
What is the pattern of bacterial causes of febrile neutropenia?
- Gram-positive bacteria (60-70%)
- Gram-negative bacilli (30-40%)
- These patterns may now relate to antibiotic prophylaxis, emerging infections, use of lines etc
What gram positive bacteria are implicated in febrile neutropenia?
- Staphylococci: MSSA, MRSA, coagulase negative
- Streptococci: viridans
- Enterococcus faecalis/faecium
What gram negative bacteria are implicated in febrile neutropenia?
- Escherichia coli
- Klebsiella spp: ESBL
- Pseudomonas aeruginosa
- Enterobacter spp
What are possible sites of infection in haematological patients?
- Respiratory tract
- Gastrointestinal (Typhlitis)
- Dental sepsis
- Mouth ulcers
- Skin sores
- Exit site of central venous catheters
- Perianal (avoid PRs!)