Infections in the compromised host. Learning Objectives At the end of this lecture, the student should be able to: list the main types of defects in immune.

Slides:



Advertisements
Similar presentations
FUNGAL DISEASES IN THE RESPIRATORY , EXCRETORY & CIRCULATORY SYSTEMS
Advertisements

The lymphatic system and immunity
Partnership for Environmental Education and Rural Health (PEER) Supported by the National Institutes of Health ORIP.
Risk of invasive H. influenzae disease in patients with chronic renal failure: a call for vaccination? M. Ulanova, S. Gravelle, N. Hawdon, S. Malik, D.
OPPORTUNISTIC FUNGAL INFECTIONS
Immune System & Oncology Nursing Care PN 143 Rebecca Maier, BSN.
Ch. 43 The Immune System.
Infections In The Immunocompromized Host Components of Host Defenses: Mechanical barriers Skin, mucous membranes, epiglottis, cilia. Granulocytes Cell.
Immunodeficiency Paula O’Leary CP4004 Lecture Nov 2010.
Infections in Patients With Cancer February 2015 Infections in Patients With Cancer1 A clinical review of risks to patients with immunocompromised systems.
Immune Response against Infectious Diseases
Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.1.
Immune deficiency Diseases (2). Immune Deficiency Disorders Immunodeficiencies can be divided into primary immunodeficiency disorders, and secondary immunodeficiency.
Chapter 10 Bacteria and Viruses. Section 10C-2 Defense against infectious disease A. Structural defense – “First line of defense” keep pathogens out!
OPPORTUNISTIC INFECTIONS IN IMMUNOCOMPROMISED PATIENTS
CLS 212 medical microbiology Mrs. Basmah Al-Maarik.
Clinical Microbiology ( MLCM- 201) Prof. Dr. Ebtisam.F. El Ghazzawi. Medical Research Institute (MRI) Alexandria University.
Principles of antibiotics use in immunocompromised patients
Ch 47 – The Body’s Defense Systems
The Immune System Chapter 43. Overview Innate vs. Acquired Immunity Innate Immunity: Present from the time of birth Nonspecific External barriers, Mucous.
IMMUNE SYSTEM Biology 2201.
Copyright © 2011, 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Chapter 38 Cancer, Immune System, and Skin Disorders.
Nosocomial infection Hospital Infection. Hospital acquired infections Nosocomial infections are those that originate or occur in a hospital or hospital-like.
بسم الله الرحمن الرحيم
CPC #2: 38 year old woman with HIV/AIDS and altered mental status October 9, 2007.
HIV related Opportunistic Diseases HIV related Opportunistic Diseases M.MEIDANI,MPH.MD.
SPM 100 Clinical Skills Lab 1 Standard Precautions Sterile Technique Daryl P. Lofaso, M.Ed, RRT.
MEDICAL TESTING Doctor requires information Patient sample collection
 Bacteria  Viruses  Fungi  Parasites  Idiopathic.
Central Nervous System Infections. RABIES.
Immune System Chris Schneider. Immune System Function The purpose of the immune system is to keep infectious microorganisms, such as certain bacteria,
Infective Endocarditis Prof DR Asem Shehabi Faculty of medicine, University of Jordan.
Lab 5: INTEGUMENTARY SYSTEM BACTERIOLOGY AND IDENTIFICATION.
Lecture 23 Immune System. Introduction A human or animal must defend itself against multitude of different pathogens including viruses, bacteria, fungi,
White Blood Cells Prepared by Dr. Hamad ALAssaf
Bone & Joints Infections. Osteomyelitis Osteomyelitis is infection of the bone. Infections can reach a bone by traveling through the bloodstream, spreading.
INFECTION CONTROL IN HSCT: USE OF HEPA-FILTER BY IYOHA OSARETIN DEPARTMENT OF MEDICAL MICROBIOLOGY UNIVERSITY OF BENIN TEACHING HOSPITAL BENIN CITY.
Principles of Disease and Epidemiology. Host and Microbe A delicate relationship exists between pathogenic microorganisms and body defenses. When the.
Inhibiting Microbial Growth in vivo CLS 212: Medical Microbiology.
IMMUNE SYSTEM OVERVIEW
SPM 100 Skills Lab 1 Standard Precautions Sterile Technique Daryl P. Lofaso, M.Ed, RRT Clinical Skills Lab Coordinator.
 list the main microorganisms responsible from UTI  explain the importance of significant bacteriuria and quantitative culture method  List the main.
CLINICAL PHARMACOLOGY OF ANTIBACTERIAL AGENTS. Actions of antibacterial drugs on bacterial cells.
Infections In The Immunocompromised Host
CLS 212 medical microbiology. What's meant by Nosocomial Infections? Any infection causing illness that wasn't present (or in its incubation period) when.
Chapter 33 Cancer, Immune System, and Skin Disorders All items and derived items © 2015, 2011 by Mosby, Inc., an imprint of Elsevier Inc. All rights reserved.
Introduction to Immunology
Infective Endocarditis
Gülden Çelik. Learning Objectives At the end of this lecture, the student should be able to: Define bacteremia, fungemia, and sepsis List the main types.
Commensal and Pathogenic Microbial Flora in Humans
Introduction to Microbiology & Handwashing
Chapter 16 Immunity to Microbes.
Chapter 15 Care of the Patient with an Immune Disorder Mosby, Inc. items and derived items copyright © 2003, 1999, 1995, 1991 Mosby, Inc.
IMMUNITY IN VULNERABLE GROUP(NEONATES & ELDERLY) Assist Prof Dr. Syed Yousaf Kazmi.
The Immune System. Protects our bodies from pathogens – disease causing agents May be bacteria, viruses, protists, fungi, etc Response could be nonspecific.
5th Semester Classes on Infectious Diseases, 8-9AM, Thursdays (LT-4)
Infections In The Immunocompromised Host
Tissue and Organ Transplantation
Principles of antibiotics use in immunocompromised patients
THE IMMUNE SYSTEM Barriers Pathogens and antigens Immune system cells
Principles of Medical Microbiology
The Chain of Infection.
Vaccinations and Prevention of Infectious Disesase
The lymphatic system and immunity
Basic Immunology CLS 212.
The Lymphatic System Pages
Blood and Lymphatic Systems
Cells with CD4 receptor on surface
The Lymphatic System and Immunity
Presentation transcript:

Infections in the compromised host

Learning Objectives At the end of this lecture, the student should be able to: list the main types of defects in immune system List the most common microorganisms associated with disease in each type of immunodeficiency List the main laboratory methods for most of the infections in immunocompromised patients

Immune system -the innate defense system (e.g. skin, mucous membranes) -the adaptive (cellular and humoral) immune system protects us from infection

The Immune system Immunocompetent host: intact Immunocompromised host: – has defects in their body's natural defenses – prone to severe and life-threatening infections !

The immunocompromised patient Defects, accidental or intentional, in the body's innate defense mechanisms deficiencies in the adaptive immune response _______________________________________ Primary immunodeficiency Acquired immunodeficiency

Primary immunodeficiency: rare – inherited or – occurs by exposure in utero to environmental factors or by other unknown mechanisms Secondary or acquired immunodeficiency – due to an underlying disease state or – occurs as a result of treatment for a disease.

Immunocompromised patients increase in number due to: – Therapy of many cancer types – Organ transplantation – HIV/AIDS

Innate immunity Primary defects: – congenital defects in phagocytic cells or complement synthesis Extracellular infections

Innate immunity Secondary defects: – disruption of the body's mechanical barriers: Burns traumatic injury major surgery Devices such as intravascular and urinary catheter procedures such as lumbar puncture or bone marrow aspiration Foreign bodies such as prostheses Obstruction

Burn wound infections Burns damage : – the body's mechanical barrier – neutrophil function – immune responses – The major pathogens in burns are aerobic and facultatively anaerobic bacteria and fungi – Septicemia in patients with burns is often polymicrobial.

The most important pathogens in burn wounds are: Pseudomonas aeruginosa and other Gram- negative rods Staphylococcus aureus Streptococcus pyogenes other streptococci enterococci. Candida spp. and Aspergillus together account for about 5% of infections. Anaerobes are rare in burn wound infections.

Surgical wound infections Staphylococcus aureus: the most important cause – May be severe – Invade the bloodstream – seed other sites heart valves: causing endocarditis bones:osteomyelitis – thereby further compromising the patient.

Urinary catheters Catheter-associated infection of the urinary tract is common Especially if catheters are left in place for >48 h. The organisms involved are usually Gram- negative rods from the patient's own fecal or periurethral flora

Intravenous and peritoneal dialysis catheter infections Staphylococci :the most common – coryneforms, Gram-negative rods and Candida are also implicated.

Infections of plastic devices in situ Coagulase-negative staphylococci, particularly Staphylococcus epidermidis, account for more than 50% of the infections These opportunists are members of the normal skin flora multiple antibiotic resistances, and agents such as a glycopeptide (vancomycin or teicoplanin) and rifampicin may be required Whenever possible the plastic device should be removed.

Percentage of infections caused by Staph. epidermidis in patients with plastic devices in situ Infections caused by Staph. epidermidis (%) Prosthetic heart valve Early (<2 months postoperatively)30-70 Late (>2 months postoperatively)20-30 Prosthetic hip10-40 Cerebrospinal fluid shunt30-65 Vascular grafts5-20 Peritoneal dialysis related30 Intravascular catheters10-50

Infections due to compromised clearance mechanisms Stasis: cystic fibrosis: Staph. aureus and Haemophilus influenzae and later with P. aeruginosa Obstruction and interruption of normal urine flow: Gram-negative organisms from the periurethral flora – Septicemia is an important complication of urinary tract infection superimposed on obstruction.

Adaptive immunity Primary defects: – T-cell defects – B-cell deficiencies – severe combined immunodeficiency

Adaptive immunity Secondary defects: malnutrition infectious diseases neoplasia irradiation chemotherapy splenectomy

Adaptive immunity Secondary defects: -The underlying immunodeficiency state determines -the nature -severity of any associated infection, and in some cases: - infection is the presenting clinical feature

Infections that cause immunosuppression ViralBacterial MeaslesMycobacterium tuberculosis MumpsMycobacterium leprae Congenital rubellaBrucella spp. Epstein-Barr virus Cytomegalovirus HIV-1, HIV-2

Treatment of disease can also cause immunosuppression Cytotoxic agents such as cyclophosphamide and azathioprine cause leukopenia or deranged T- and B- cell function Corticosteroids reduce the number of circulating leukocytes, monocytes and eosinophils and suppress leukocyte accumulation at sites of inflammation Radiotherapy adversely affects the proliferation of lymphoid cells.

Treatment for neoplastic disease – patient becomes immunocompromised as a result of both the disease and the treatment. – Due to improvements in medical technology, many immune defects, particularly immunosuppression resulting from radiotherapy or cytotoxic drugs, are transient, and patients who survive the period of immunosuppression have a good chance of a complete recovery.

Hematologic malignancy and bone marrow transplant infections A lack of circulating neutrophils following bone marrow failure predisposes to infection Opportunistic pathogens in neutropenic patients and organ transplant recipients: – Bacteria – Fungi – Parasites Toxoplasma gondii Strongyloides stercoralis

Hematologic malignancy and bone marrow transplant infections – Viruses Herpesviruses, Hepatitis B Hepatitis C Polyomaviruses, e.g. BKV, JCV Adenoviruses Cytomegalovirus (CMV) infections: associated with graft-versus-host disease as well as immunosuppressive therapy.

Solid organ transplant infections Most infections occur within 3-4 months of transplantation Suppression of a patient's cell-mediated immunity is necessary to prevent rejection of a grafted organ, and the cytotoxic regimens used usually suppress humoral immunity to some extent as well. In addition, high doses of corticosteroids to suppress inflammatory responses are required. The combination of these factors results in a severely compromised host

HIV/AIDS As the HIV-infected individual progresses to AIDS, organisms that are usually controlled by cell- mediated immunity are able to reactivate to cause disseminated infections not seen in the immunologically normal individual.

Opportunistic pathogens FungiCandida spp. Aspergillus spp. Cryptococcus neoformans Histoplasma capsulatum Pneumocystis jiroveci

Downloaded from: StudentConsult (on 17 September :51 PM) © 2005 Elsevier

Downloaded from: StudentConsult (on 17 September :51 PM) © 2005 Elsevier

Pneumocystis jiroveci causes symptomatic disease in people whose cellular immune mechanisms are deficient. high incidence of pneumonia – in patients receiving immunosuppressive therapy to prevent transplant rejection and – in people with HIV.

Pneumocystis jiroveci the organism cannot be isolated in expectorated sputum using conventional culture methods invasive techniques such as bronchoalveolar lavage or open lung biopsy are required. The organism can be demonstrated by silver or immunofluorescent stains. DNA amplification by the polymerase chain reaction improves the sensitivity of the diagnostic tests.

Downloaded from: StudentConsult (on 17 September :51 PM) © 2005 Elsevier

Actinomycetes contain two pathogenic genera, Actinomyces and Nocardia. The lung is usually the primary site, but infection can spread to the skin, kidney or central nervous system

Mycobacterium avium-intracellulare disease is often a terminal event in AIDS

Protozoa and helminths Cryptosporidium and Isospora belli infections cause severe diarrhea in AIDS Strongyloides stercoralis

Certain virus infections both more common and more severe in compromised patients, and regular surveillance is critical Many of these represent reactivation of latent infections. Pre-transplantation baseline serology is carried out to determine both the donor and recipient status for a number of virus infections, including HIV, hepatitis B and C, CMV, EBV and HSV. CMV quantitative DNA monitoring is carried out on blood samples on a regular basis post- transplantation to detect early infection and start antiviral therapy (preemptive therapy)as soon as possible.

HSV, VZV may reactivate HHV-8 has been associated with the development of Kaposi's sarcoma (KS) in individuals with AIDS EBV infection can lead to tumor development Respiratory viruses

Polyoma viruses BK and JC virus can reactivate. can cause hemorrhagic cystitis and progressive multifocal leukoencephalopathy

Compromised patients Infection may be due to: – any of the pathogens capable of infecting immunocompetent individuals. – opportunist pathogens. – The type of infection is related to the nature of the compromise Effective antimicrobial therapy is often difficult to achieve in the absence of a functional immune response, even when the pathogen is susceptible to the drug in vitro For microorganisms involved direct methods for detection especially nucleic acid detection techniques are prefered.

Reference: 7th ed 2013