Infections In The Immunocompromised Host Objectives of this lecture: To review the components of the host defense mechanisms To recognize the importance of immunodeficiency and infections To know the common infectious complications in major immunodeficiency categories(other than HIV&AIDS)

Infections In The Immunocompromised Host Components of Host Defenses: Mechanical barriers Skin, mucous membranes, epiglottis, cilia. Granulocytes Cell mediated Immunity Macrophages, T-lymphocytes, NKC, cytokines Humoral Immunity B-lymphocytes, immunoglobulins, complements Spleen Davidson's Principles and Practice of Medicine 20th edition chapter 4 pages 64-75

Infections In The Immunocompromized Host The importance of infections in IC host: Increasing numbers of Immunocompromised patients. Seriousness of infections in those patients. Infections with unusual, nonpathogenic microorganisms. Atypical presentation of infections by common pathogens

Infections In The Immunocompromized Host Causes of immune deficiency: Primary (congenital); Rare, more common in children e.g chronic granulomatus disease, combined immunedifiency syndrome, specific Ig deficiency, others. Secondary (acquired); The commonest, there are many causes like; Extremes of age, pregnancy, infections, malignancy, chemotherapy, steroids, burns, trauma, procedures, connective tissue diseases, chronic diseases like DM,CRF etc. Davidson's Principles and Practice of Medicine 20th edition chapter 4 pages 64-75

Infections In The Immunocompromized Host Host Defects and Associated Prevalent Pathogens Staph. Aureus,CNSS, V strep, Enterococci, E. coli, Pseudomonas aeruginosa, K.pneumoniae, other gram –ve bacilli, Aspergillus spp Granulocytopenia CNSS, Staph. Aureus, pseudomonas aeruginosa and other gram-ve bacilli, candida spp, V. strep, enterococci, HSV. Damaged skin and mucous membrane HSV, VZ, EBV, CMV, RSV, M. tuberculosis, Aspergillus spp and other fungi, Toxoplasma gondi. Impaired CMI Streptococcus pneumoniae, Haemophilus influenzae Impaired humoral immunity Neisseria meningitides. Spleen dysfunction Neisseria meningitides, Neisseria gonorrhea Complement deficiency

Fever In Neutropenic Patient Definition: Fever: Oral temperature of 38c for more than two hours or single temperature of 38.3c or more. Neutropenia: A Neutrophil count of <500 cells/mm³ or a count of <1000 cells/mm³ with a predicted decline to 500/mm Approach to patient: Careful history and examination, investigations (like blood cultures, urine culture, CXR, others), then start antibiotic therapy to cover the most likely organisms. IDSA guidelines CID;2002:34:730-751

Fever In Neutropenic Patient SEQUENTIAL INFECTIVE EVENTS

Fever In Neutropenic Patient Causes of fever in neutropenic patients;

Fever In Neutropenic Patient IDSA guidelines CID;2002:34:730-751

IDSA guidelines CID;2002:34:730-751

IDSA guidelines CID;2002:34:730-751

IDSA guidelines CID;2002:34:730-751

IDSA guidelines CID;2002:34:730-751

IDSA guidelines CID;2002:34:730-751

Fever In Neutropenic Patient Treatment: Antibacterial like; pipracilline+ aminoglycoside or ceftazidime+ aminoglycoside or Imipenem, vancomycine. Antifungal like; Amphotericine B, Fluconazole Antiviral like; Acyclovir Granulocyte stimulating factors

Infections in Solid-Organ Transplant Recipients Factors affecting the incidence of infections: The type of organ transplanted. The degree of immunosupression. The need for additional antirejection therapy. The occurrence of surgical complications. Presence of latent infection in the donor or recipient. CID;2001 (supp 1):S5-S8

Infections in Organ Transplant Recipients Common infection in Specific Organ transplant: Bone marrow transplant Bloodstream infections, pneumonia, viral infections Kidney transplant Urinary tract infections. Liver transplant Intra abdominal infections. Heart and Heart-Lung Chest, Mediastinitis transplant

CMR;1997:277-297

Infections in Organ Transplant Recipients TB,Legionella Histoplasma,Nocardia,Toxoplazma,Pneomocystis Candida,Aspergillosis EBV,CMV,HBV VZV,CMV retinitis Common bacteria 1 2 3 4 5 6 7 8 9 10 Months post transplantation CID;2001 (supp 1):S5-S8

INFECTIONS IN IMMUNOCOMPROMISED HOST Suggested readings: Davidson's principles and practice of medicine 20th edition Harrison's Principles of Internal Medicine 16th or 17th edition