Fever in the Immunocompromised Host (Small Group Session 27) Flashcards
Describe how corticosteroids may lead to infection.
Neutrophilia
- Increased neutrophil release from marrow
- Demargination of neutrophils
- Decrease egress from circulation into tissues (imparied chemotaxis)
Lymphopenia, Eosinopenia, Monocytopenia
- Increased destruction of WBCs
Qualitative WBC Changes
- Decreased IgG synthesis imparied by Ag presentation
- Impaired chemotaxis by phagocytic cells
- Decreased Fc receptor expression by phagocytic cells
- Impaired phagocytosis
All of these factors result in immune suppression.
Provide the following information for a complement deficiency:
- Presentation
- Example
- Investigation
- Treatment
Complement deficiency
Presentation: Neisseria, pyogenic bacteria, immune complex disease
Example: C5 deficiency
Investigation: CH50
Treatment: Vaccination, assessment of fever, medicalert
Provide the following information for a phagocytic deficiency:
- Presentation
- Example
- Investigation
- Treatment
Phagocyte Deficiency
Presentation: bacteria, fungus
Example: Chronic Granulomatous Disease (CGD)
Investigations: Oxidative burst, nitroblue-tetrazolium (NBT), dihydrorhodamine (DHR)
Treatment: Prophylactic antibiotics, and antifungal, Interferon gamma (IFN-g), bone marrow transplant
Provide the following information for a humoral immune deficiency:
- Presentation
- Example
- Investigation
- Treatment
Humoral Immunity Deficiency
Presentation: sinopulmonary, bacterial
Example: CVID = Chronic Variable Immune Deficiency
Investigation: IgGAME, vaccine titers
Treatment: Replacement IgG
Provide the following information for a cellular immunity deficiency:
- Presentation
- Example
- Investigation
- Treatment
Cellular Immune Deficiency
Presentation: viral, fungal, opportunistic
Example: Chronic mucocutaneous candidiasis
Investigation: Refer to immunology
Treatment: Anti-fungals
Provide the following information for a combined deficiency:
- Presentation
- Example
- Investigation
- Treatment
Combined Immune Deficiency
Presentation: bacterial, viral, fungal, opportunistic
Example: Severe Combined Immunodeficiency
Investigations: IgGAME, lymphocyte subsets, and function, REFER
Treatment: BMT asap
What organisms are likely to infect a cenral venous catheter?
- Staphylococcus aureus
- Coagulase negative staphylococcus
- Gram negative bacilli (resistant to antibiotics)
- Candida
What organisms are likely to cause chest infections, specifically which organisms are related to hospital acquired chest infections?
Hospital acquired (>3 days)
- Pseudomonas
- Staphylococcus aureus
- Gram negatie bacilli
- E. coli
- Enterobacteriaceae
Others
- Candida
- Aspergillus
- Mucormycosis
- PJP (Pneumocystis jiroveci pneumonia)
What organisms are likely to cause infections in the oropharynx?
- Viridans streptococcus
- Anaerobes
- Candida
- Herpes Simplex Virus
- Cytomegalovirus
What organisms are likely to cause infections of the GI tract?
- Enterobacteriaceae; E. coli, Klebsiella
- Anaerobes
- Candida
- Enterococcus
- Viridans Streptococcus
A 44 yr old woman, who 15 days earlier received induction chemotherapy for acute myelogenous leukemia, presents with a 24-hr history of fever or rigors. On examination the patient has severe oropharyngeal mucositis, tachypnea, cough and tenderness and erythema along the tunnel of the central venous catheter in her right subclavian vein. Laboratory tests reveal a WBC of 0.4 x 109/L with all cells reported as lymphocytes. CXR is unremarkable.
State the defects in host defence that are present in this patient.
Host Defence Defects
- Chemotherapy = T cell deficit
- Barrier defect = catheter, mucositis
- No neutrophils
- AML = suppression of normal hematopoietic cells; decreased neutrophils, RBCs, platelets
A 44 yr old woman, who 15 days earlier received induction chemotherapy for acute myelogenous leukemia, presents with a 24-hr history of fever or rigors. On examination the patient has severe oropharyngeal mucositis, tachypnea, cough and tenderness and erythema along the tunnel of the central venous catheter in her right subclavian vein. Laboratory tests reveal a WBC of 0.4 x 109/L with all cells reported as lymphocytes. CXR is unremarkable.
What is the appropriate managment of this patient in terms of treating her infection?
- Broad spectrum antibiotics: piperacillin-tazobactam
- Vancomycin (MRSA coverage)
- Fluconazole (Fungal; candida coverage)
- Antibiotic treatment can be narrowed when cultures return
What are the clinical features of infectious mononucleosis and the laboratory abnormalities most commonly found in association with infectious mononucleosis.
Infectious Mononucleosis
Clinical features
- Fever
- Fatigue
- Pharyngitis
- Adenopathy
- Less commonly: splenomegaly, rash, Guillian-Barre, night sweats
Lab abnormalities
- Lymphocytosis: majority are CD8 cells
- Atypical lymphocytes (but acting normally for the circumstances)
- EBV serology
- Monospot
A 24 yr old man from India with hemophilia A is referred to you for oropharyngeal candidiasis, wt loss and fatigue. 6 yrs earlier, shortly after he immigrated to Canada, the pt had been seen by a family physician for pharyngitis, non-tender bilateral cervical adenopathy, fever and splenomegaly. The patient had been told that he had infectious mononucleosis. Three months ago the patient had an episode of shingles (herpes zoster) involving the right T6 dermatome.
What is the significance of the pharyngitis, cervical adenopathy, fever and splenomegaly at his initial presentation?
The pharyngitis, cervical adenopathy, fever and splenomegaly at presentation is likely due to the contration of HIV via blood transfusions. During the “Acute Infection” stage 40-90% of pts experience a “flu-like” illness (may include fever, pharyngitis, lymphadenopathy, rash, arthralgias, myalgias, H/A, GI symptoms, oral ulcers, wt. loss) 2-6 wks post exposure and lasting 10-15 days.
A 5 mth old male is admitted to hospital in Medicine Hat for the second time with respiratory distress. On his first admission a month earlier his parents were told that he may have asthma and he was sent home with salbutamol but he never improved. He has had oral thrush since 3 wks of life despite topical treatment with nystatin on numerous occasions.
What is at the top of your differential diagnosis?
Severe Combined Immunodeficiency
