Term | Definition |
Immune System Functions | Protect from foreign entities; identify and destroy harmful cells; remove debris. |
Antigen | Foreign Substance, cell, toxin or protein causing immune system reaction |
Immunocompetent | Body correctly identifies, destroys and removed inappropriate entities |
Immunocompromised | a.k.a immunodeficient; body misidentifies or can not protect from inappropriate entities - over or under reacts |
First Line of Immune Defenses | Surface (barrier) - Skin & Mucus membranes |
Second Line of immune defenses | Cellular (nonspecific) - Phagocytes/Macrophages (destroy);Inflammatory responses (localizes; attracts phagocytes);Fever (weakens or destroys);Antimicrobial proteins (complement system);Interferons (mobilize immune system);Natural Killer Cells (cell lysis) |
Third Line of immune defenses | Immune Response - Antibody-mediated immune response: humoral - B-lymphocytes (B-cells)
Cell mediated immune response - T-Lymphocytes (T-Cells) |
B-Lymphocytes (B-Cells) | Antibody-Mediated Immune Response: Humoral
Activated by antigens and T-Cells
Produce immunoglobulins |
T-Lymphocytes (T-Cells) | Cell-Mediated immune response
Attack viruses, bacterial & Malignant Cells
Helper T-Cells (CD4 & T4 cells) stimulate the immune system
Cytotoxic Cells: attack Antigens
Suppressor T-Cells (T8): inhibit the immune system |
Hypersensitivity | Abnormal, harmful response to antigen |
Allergen | Exogenous antigen causing hypersensitivity reaction |
Allergy | Hypersensitivity reaction to normally harmless substance; Mild to life threatening |
Immediate response | Antigen-Antibody (I,II,III) |
Delayed response | Antigen-lymphocyte (IV) |
Type I Hypersensitivity Reaction | IgE-Mediated Hypersensitivity - IgE bound to mast cells and basophils
degranulation: release histamine, acetylcholine, kinins, heparin, chemotactic factors ---> inflammatory response |
IgE Mediated Hypersensitivity S & Sx | Uneasiness or sense of doom; hives; lightheadedness; itching palms or scalp; angioedema; uvula & larynx swelling; bronchial constriction; vasodilation & vascular permeability; increased gut permeability |
Allergic Reactions - IgE mediated | asthma, conjunctivitis, rhinitis, hives |
Anaphylaxis | acute, highly sensitive - vasodilation, increased capillary permeability; smooth muscle contraction; bronchial constriction |
Anaphylactic shock | impaired tissue perfusion & hypotension from vasodilation and vascular fluid loss - Emergency mgmt = epinephrine SQ 1:1000; repeat in 15 min (IV=epi 1:100,000); tourniquet control, antihistamines, O2, bronchodilators |
Type II hypersensitivity reaction | Cytotoxic Hypersensitivity - Reaction to foreign tissue or cell |
Cytotoxic hypersensitivity (type II) | Common = hemolytic transfusion, graft or medication reaction; autoimmune
IgG or IgM antibodies bind to antigen and initiate complement cascade; cell lysis and phagocytosis destroys antigen-bearing (ABO or Rh) target cells; killer T-Cells activated |
Emergency Management for Cytotoxic (type II) reaction | Stop Transfusion or Rx, administer epinephrine, O2 & diuretics |
Type III Hypersensitivity Reaction | Immune Complex-Mediated = circulating immune complexes are deposited in small vessels and extra-vascular tissues causing tissue damage (kidneys, lungs, joints) |
Immune Complex-Mediated (type III) | Activates complement cascade, neutrophils, machrophages and mast cells. |
Immune Complex-mediated reactions S & Sx | fever, rash, muscle pain, glomerulonephritis, lung inflammation |
Immune Complex-mediated reactions treatment | For generalized reactions: "Serum sickness" (horse anti-tetanus toxoid = no longer used); penicillins, sulfonamides |
Type IV hypersensitivity reactions | Delayed Hypersensitivity = cell mediated NOT antibody mediated
Delayed NOT immediate (24-48 hours) |
Delayed Hypersensitivity Reactions | Exaggerated antigen & cell-mediated reaction.
lysozymes from macrophages and killer t-cells
sx: edema, ischemia & tissue damage |
Delayed Hypersensitivity Reaction Causes | Contact dermatitis, poision ivy, latex, +PPD - can escalate from Type IV (contact dermatitis) to Type I (anaphylaxis) with repeat exposure |
Testing for Hypersensitivity Reactions | WBC Count with Diff (eosinophilia) ;RadioAllergoSorbenT Test (RAST) ;Blood type & Cross match (pre-transfusion); Complement & immune complexes assays:type III autoimmune disorders; Puncture,intradermal, patch testing; food diaries, elimination,re-intro |
Indirect Coombs | Blood type & cross match -
Circulating non-ABO antibodies |
Direct Coombs | RBC-bound antibodies |
Immunotherapy | aka desensitization aka hyposensitization: escalating exposure to dilute allergen |
Plasmapheresis | removal of harmful components in plasma by passing the blood through a separator to remove immune complexes and return RBCs to patient |
diphenhydramine (Benadryl) | antihistamine |
epinephrine (adrenalin) | B-adrenergic sympathomimetics |
cromolyn sodium (NasalCrom; Intal) | Mast Cell Stabalizer |
prednisone (deltasone) | Steroids (glucocorticoids) |
Common Nursing Dx for Hypersensitivity Reactions | Ineffective airway clearance, decreased cardiac output, risk for injury, knowledge deficit |
Immune System Dysfunction | Impaired self-recognition treating 'self' as 'other' |
Organ-specific | antibodies for specific tissues (hashimoto's thyroiditis) |
Organ non-specific | results of reaction may concentrate in specific tissues (glomerulonephritis) |
Systemic | multiple targets (rheumatoid arthritis; system lupus erythematosus) |
Autoimmune disorder | genetic or familial component; females > males; overlap/multiple disorders; abnormal stressor precedes onset; progressive relapsing-remitting common |
Medications for autoimmune disorders | Anti-inflammatory: ASA, NSAIDS, corticosteroids
Anti-rheumatic: gold salts, DMARDS (methotrexate)
Replacement: levothyroxine, insulin |
Theories of Autoimmune disorders | Antigenic mimicry: 'self' and 'other' too close; changes in condition of host causing auto-antibody production; inadequate suppressor T-cells; excessive B-cell antibody production; mother-infant trans; viruses;release of sequestered antigens |
Serological Assays | Antinuclear antibody (ANA): non-specific
Lupus Erythematuosus cell test (LE): non-specific
Rheumatoid factor (RF): blood:saline detection <1:20=elderly; 1:20-1:80= SLE, scleroderma, sclerosis, TB; >1:80=RA |
Complement Assay | C1 through C9 counts & ratios |
Common Nursing Diagnosis for AutoImmune Disorders | Activity intolerance, body image disturbance |
HIV stands for ? | Human Immunodeficiency Virus |
HIV Epidemiology in U.S. | U.S. 1.2 million (25% unaware)
60% = men sexually active with other men (MSM)
20% = men injection drug abuse
20% = women
75% heterosexual contact;25% IV drug abuse
1/2 of all HIV cases = African American
Youth 15-24=40% new cases; adults >50=10% |
HIV Epidemiology Globally | 33 million; 2.5 million new cases yearly; 2 million people die each year
sub-saharan africa - 23 million
eastern europe - 1.6 million
Asia = 5 million (half in India) |
HIV types | 2 Genetically distinct types : HIV1 & HIV2 - both zoomotic introductions (non-human primates) |
Retrovirus | subgroup known as "slow" viruses; long interval between initial infection & onset of serious s&sx |
Genes of Ribonucleic Acid (RNA) | only replicate inside of cells with CD4 antigens; use enzyme (reverse transcriptase) to convert its RNA to DNA |
CD4 Cells aka Helper T-Cells | immune system leukocytes; seek out and attach to foreign bodies; HIV treatment and disease indicator (n=600-1500 cells/mL3 blood) |
Seroconversion | antibodies produced in response to viral proteins, even if virus inactive |
Viral load | amount of HIV in person; measured via blood count; changes during dif phases of disease; undetectable viral load early on |
HIV transmission | Direct body fluid transmission required - blood, semen, vaginal/cervical secretions, CSF, breast milk, saliva |
HIV Transmission - Sexual contact | virus afforded direct access to blood stream; virus infects mucosal lining macrophages; women>men to acquire HIV during intercourse;anal sex is most risky form unprotected sex;oral is least risky |
HIV Transmission - Parenteral blood exposure | Virus has direct access to blood stream; IV drug use |
HIV Transmission - Vertical Transmission | MOther to baby; during pregnancy, delivery or breast feeding
Risk Reduction: antiretroviral drugs, C-section, formula fed; interventions decreased USA transmission from 25 to 2% |
Post Exposure Prophylaxis (PEP) | Occupational health or emergency department - Goal: prevent establishment of HIV infection
HIV testing (nurse & pt); Antiviral meds:2-3meds for 28 days - zidovudine (Retrovir;ZDV;AZT)+ lamivudine (Epivir,3TC) (single pill=Combivir); f/u testing |
HIV Testing | 2006 CDC recommendations: WI: distinct concent; education & referral required; pts 13-654,all health care settings,preg women, pts starting Tb tx, Pts with STD dx, annual for high risk |
HIV Testing - ELISA | Enzyme Linked Immunosorbent Assay (ELISA) - Initial test - tests for antibodies (not virus); up to 12 weeks for the test to be true positive; ELISA highly sensitive (99.5%) after 13 weeks |
HIV Testing - Western Blot Assay | Test for antibodies; less prone to false positive results (99.9%); done to confirm + ELISA result; more reliable, expensive, time consuming than ELISA |
HIV Testing - Rapid Screening Tests | Approved by FDA; OraQuick, multispot, Reveal, Uni-Gold; provide results in 15-30min; uses either whole blood or oral fluids; follow up ELISA and/or western blood suggested |
HIV Clinical Manifestations | Initially virus affects T-Cells and macrophages; infected cells migrate to regional lymph tissue; within 4-10 days viral particles are releases into blood stream; brief intense period of viral replication; viral load = amount HIV actively replicating |
Early Stage HIV | "Acute Retroviral Syndrome" - Days to weeks after exposure; S&Sx: resolve in 1-2 weeks: fever, pharyngitits, arthralgia, myalgia, anorexia, maculopapular rash, fatigue, lymphadenopathy, N/V, abd cramping, cephalgia - viral load is high |
Latent Stage HIV | "Asymptomatic" - 3-10 years after acute phase (mean = 8-10 years); remain contagious; s/sx: none or lymphadenopathy - generalized persistent enlargement of >2 non-inguinal chain lymph nodes of unknown etiology |
Transition Stage/Advanced HIV | "AIDS" - 3-10 years after acute phase; s/sx=generalized malaise, fatigue, fever, night sweats, unintended wt loss, dry skin or rashes, GI disturbances, AIDS-defining illness |
Criteria for Transition Stage/Advanced HIV (AIDS) | seropositive for HIV; <200 CD4 cells/mm3 or <14% CD4 lymphocytes
Opportunistic infection or disease - commonly a reactivation of an infection
Generally not found in well-functioning immune system |
AIDS Defining Illnesses | Candidiasis of bronchi,trachea, lungs or esopageal; invasive cervical Ca;encephalopathy; Herpes simplex; kaposi's sarcoma; lymphoma; mycobacterium Tb; recurrent pneumonia; toxoplasmosis of brain; wasting syndrome due to HIV |
AIDS Clinical Manifestations | GI: nearly universal; possible target organ
Pulmonary: major morbidity and mortality
Cutaneous; Neurological: HIV invades early; Renal; Ocular: infectious & non-infectious; People with AIDS living longer: lung dz, rectal ca, kidney dz, DM, depression |
AntiRetroviral Therapies (ART) | Changed HIV progression & Prognosis; Four main classes: NRTI, NNRTI, PI, and entry/fusion inhibitors; HAART: combinations; Goals: suppress infection (improve health); opportunistic infection prophylaxis; stim hematopoesis; treat AIDS defining illnesses |
Nucleoside Reverese Transcriptase Inhibitors (NRTI) | Block reverse transcriptase enzyme; replication process 'decoys' (prevent RNA in DNA); slow HIV replication; Improve CD4 counts |
Non-Neucleoside Reverse Transcriptase Inhibitors (NNRTI) | Works similar to NRTI; binds to dif site; improves CD4 counts; decreases viral load; only one NNRTI at a time |
Protease Inhibitors (PI) | Prevents protease (enzyme) converting DNA to RNA; decreases viral load, slows HIV replication - lipodystrophy common: elevated cholesterol & trig, insulin resistance & DM, abd obesity w/ skeletal wasting; many med interactions & interferences |
Entry Inhibitor aka Fusion Inhibitor | Resistant strains of HIV; prevents HIV from entering cells; blocks interaction of HIV surface proteins w/ CD4 cell surface; decreases viral load; increases CD4 count; ex. enfuvirtide (fuzeon), new in 2003, must reconstitute drug |
CCR-5 Receptor Antagonist | Resistant strain of HIV;blocks HIV from attaching to CCR5 protein; ex. maraviroc (Selzentry); fewer side effects (esp neurophsych), favorable lipid profile, reduces inflammation, increases CD4 count more than other ARTS, new in 2007 |
Integrase Inhibitors | ART - Prevents HIV DNA insertion in human DNA; sig reduction in viral load; administered with other ART, ex. ralegravir (Isentress), new in 2007 |
Common Adverse Effects w/ ART's | N/V, hyperlipidemia, sedation, insulin resistance, DM, CAD, Periph neuropathy, nephrolithiasis, hypersensitivity reaction, diarrhea, anemia, insomnia, renal failure, lactic acidosis, pacnreatitis, hepatic toxicity, skin nodules |
Highly Active Antiretroviral Therapy (HAART) | Combo of 3 categories: NRTI, NNRTI, PI; consist of atleast _ medications; sig decreases CD4; supresses viral load; "standard of care", do not start regimen until ready and capable of compliance |
Monitoring of ART | Regular serology - CBC, liver, renal function, CD4, viral load; adherence to med regimen - med side effects, perceived barriers to adherence = physical, psychosocial, financial |
Drug Resistance ART | NNRTI>NRTI>PI; related to inadequate dosing (many factors); testing for resistance - Genotypic & Phenotypic HIV Drug Resistance Assays |
AIDS Dementia Complex | Direct effect of virus on brain; CNS infections & lesions including toxoplasmosis, non-hodgkins lymphoma, cryptococcal meningitis, CMV infections; children=prog encephalopathy w/ milestone reversal,cog/motor dysfunction |
Cancer & AIDS | 30-40% of people with AIDS get cancer - Kaposi's Sarcoma; Lymphomas (esp Non-Hodgkins); Invasive cervical carcinoma; Cancers may be related to problem w/ immune system, damge to the immune system (disease &/or medications), meds |
Nursing Diagnoses for AIDS | Ineffective coping r/t stigma, terminal illness; imbalance nutrition, less than body requirements r/t diarrhea, inability to prepare meals; Infeffective sexual patterns r/t unsafe sexual practives, imparied relationship w/ sig other |