HOSA Immunologic Diseases and Conditions

Immunocompetent

when immune system reacts appropriately to antigen and homeostasis is maintained

Immunoincompetent

When immune system is either too weak or too strong, leading to disruption of homeostasis

Hyperactive Response

Allergies, when immune system is excessive

Immunodeficiency

Immune responses are inadequate

Autoimmune Disorders

Immune response is misdirected

Transplant Rejection

When internal organ transplants are not correctly matched; can result in hyperacute reaction, where during operation transplant must automatically be removed, acute rejection, where after first few weeks antirejection drugs ineffective, chronic rejection, where over months/years inflammation of tissues in organ deteriorates transplanted organ

Immunogen

Usually protein, which body recognizes as foreign, producing antibodies in response to that specific antigen

Natural Killer Cells

kill virus-infected cells and tumor cells

Macrophages

Phagocytoses bacteria, viruses, and other foreign substances

Polymorphonuclear Neutrophils

phagocytose bacteria (PMNs)

Hematopoietic System

Body system which regulates and recovers all blood types

T Lymphocytes

T cells, which multiply and combine w/ specific foreign antigens derived from viruses, fungi, tumors, or transplanted tissues; code for recognized self-antigens to destroy them

Cytotoxic T-Cells

Killer T-cells, directly destroy virus-infected cells, tumors, allograft cells by inducing apoptosis through release of toxins

Helper T-Cells

Stimulate B cells to differentiate into plasma cells to produce more antibodies, activating killer t-cells and macrophages, carrying CD4 glycoprotein on surface

Suppressor T-Cells

Inhibit B/T cells activity to moderate immune system

Memory T Cells

Remain dormant until activated by original antigen, allowing potent response years after original exposure

Reticuloendothelial System

Produce antibody-mediated immunity that protects body against bacterial/viral infections; can proliferate and form clones of cells which respond to specific antigens

Immunoglobulins

Coating which allows B cells to recognize foreign protein and stimulate antigen/body response; five types IgM/G/A/D/E, usually all present in immune response but amounts varying

IgG

75-85% of total; in blood plasma; primary/secondary immune response, inactivates antigens, neutralizes toxins, crosses placenta to provide immunity for newborn, responsible for Rh reactions

IgA

5-15% of total; in saliva, mucus, tears, breast milk; protects mucus membranes on body surfaces, immunity for newborns

IgM

5-10% of total; Attached to B cells, released into plasma during immune response; causes antigens to clump together, responsible for transfusion reactions in ABO blood typing systems

IgD

0.2%, on B cells; receptor sites for antigens in B cells, binding w/ antigen results in B cell activation

IgE

0.5%, prod by plasma cells in music membranes and tonsils; binds to mast cells and basophils, causing release of histamine, responsible for allergic reactions

Acquired Immunity

Active or Passive; Active when person had previous exposure to pathogen but was asymptomatic, passive when immunity bypasses body’s immune response to afford benefit of immediate antibody availability, being given immune substances created outside person’s body for temporary immunity, e.g. breast milk feeding; can be natural or artificial, depending on origin of antibodies, either in/out of body

AIDS

Progressive impairment of immune system caused by HIV, destroying organ systems, and very fatal; develop flu like illness, weight loss, lymphadenopathy, fatigue; T cell amounts lower, pneumonia, fever; HIV attacks helper T lymphocytes (CD4 cells), which safeguard against tumors; destruction of T cells and proliferation of HIV leaves body defenseless from infection, can also directly damage NS; spread by sexual contact, transmitted by blood transfusion, inherited by mother; No treatment currently, ultimately fatal but numbers have dropped w/ inc use of HAART therapy and prophylactic antibiotics

Common Variable Immunodeficiency

Acquired Hypogammaglobulinemia; acquired B cell deficiency resulting from absence of antibody prod; chronic/recurrent infections, gastrointestinal disease, weight loss, diarrhea, abdominal pain, lymphadenopathy (swollen lymph nodes), splenomegaly (enlarged spleen), hepatomegaly (enlarged liver); cause not known, speculated to be result of immune system dysregulation leading to failure of B-cell differentiation; Treatment aimed at preventing infections, adequate rest, immune globulin replacement on regular basis; poor prognosis and no prevention

Selective IgA Deficiency

Selective IgA Defici Low IgA, often asymptomatic due to compensatory inc in IgM production; symptoms include sinopulmonary infections, gastrointestinal infections, constant autoimmune diseases, food allergies; relatively common, often inherited in autosomal dom/rec pattern, no cure, but treatment focused on prevention of infection given thru antibiotics; neutral prognosis, no prevention

X-Linked Agammagloblinemia

Bruton’s Agammaglobulinemia is severe B cell deficiency; recurrent severe gram-positive infections, conjunctivitis, dental caries, juvenile rheumatic arthritis; Defect on Bruton tyrosine kinase (BTK) which normally expressed in B cells, tests show low IgM/A/G; treatment improves immune defenses by intravenous infusions of immune globulins, leading to good prognosis w/ unknown prevention

Severe Combined Immunodeficiency (SCID)

Group of disorders that results from disturbance in development of both T/B cells, leading to their absence; concurrent infections, enlarged tonsils absent; inherited either X-linked or autosomal recessive, causing defect in stem cell differentiation, blocking cytokine pathways necessary for lymphocyte development; treated by bone marrow transplantation, no prevention known

DiGeorge’s Anomaly

Thymic Hypoplasia, Aplasia; congenital immunodeficiency resulting from absent thymus; wide-set, downward slanting eyes, low-set ears, small mouth, thymus/parathyroid glands absent, hypocalcemia; abnormal development of pharyngeal patches during 12th week of gestation causes thymus gland to be underdeveloped leading to defect in T-cell function and dec B-cell count; Vitamin D and parathyroid hormone replacement necessary, intravenous immune globulin and prophylactic antibiotics helpful to reduce infection; usually fatal in children, no prevention

Chronic Mucocutaneous Candidiasis (CMC)

group of disorders charact by persistent and recurrent candidal infections of skin, nails, and mucus membranes; disorders unified by inclusion of deficient cell-mediated immunity to Candida organisms; 2-3 yo, lesions on skin, nails, vagina, mouth sores, rash early stages; other infections more common; chronic oral candidiasis, hypoparathyroidism, ovarian failure, etc.; immunocompetency → Candida albicans, as T-cell deficit specific to candida leads to infection; KOH scrapings from lesion indicative along with blood studies showing normal T-cell circulation except to Candida; elimination of infections w/ antifungal agents treats, transfer of T lymphocytes; death uncommon, good prognosis, unknown prevention

Wiskott-Aldrich

Congenital, low B/T-cell function; eczema, thrombocytopenia (low platelet count) w/ severe bleeding, hematemesis, epistaxis; young, w/ bleeding subsiding w/ inc age/eczema; immediate medical care based on bleeding; from X-linked trait only in males in WASP gene, expressed in hematopoietic cells → short lived platelets and defects in platelet synthesis; Bone marrow transplant is only curative therapy w/ high success, splenectomy may help if no BMT; good prognosis for w/ BMT, prevention unknown

Autoimmune Diseases

Autoantibodies develop and destroy body tissue, immune system misidentifies and develops antibodies against own cells

Autoimmune Hemolytic Anemia

RBCs destroyed by antibodies; fatigue, weakness, fever, dyspnea, pale skin, hypertensive easily; misguided immune response → B cells produce antibodies not identified by RBC as self, resulting in attack on red corpuscles; warm antibody (agglutinin) associated w/ excess IgG antibodies, stimulated by penicillins, autoimmune diseases, malignancies, anemia and cold antibody (agglutinin) anemia w/ igM at colder temps (30 C) in conjunction w/ viruses; Coombs test indicates antibody-coated RBC which agglutinate when antiglobulin present; RBCs spherical; RBC count, platelet count, hematocrit all decreased; treatment involves identifying hot/cold (i.e drug or infection causing); warm uses corticosteroids to reduce antibody production or splenectomy, red cell transfusions, cold is avoidance of cold; warm has good prognosis, cold less due to genetic background, prevention unknown

Pernicious Anemia

Chronic atrophic gastritis decreases gastric production of HCl and intrinsic factor, impairment of B₁₂ absorption; sore tongue, weakness, numbness in extremities, pale facial features, anorexia, vomiting, vulnerability to infections; neuritis from B₁₂ deficiencies demyelination of peripheral nerves; ataxia, headaches; complaints of weakness or cardiovascular system prepares diagnosis; due to antiparietal cells which are cytotoxic (toxic to cells) to parietal cells; intrinsic factor must be present in gastric mucosa for vitamin B₁₂ absorption, B₁₂ required for RBC formation; Pernicious associated w/ Grave’s, Hashimotos’s thyroiditis, more common in Northern Europeans 40-70 yo;  Schilling test for presence of antiparietal ells or antiintrinsic factor antibodies, decreased hemoglobin and RBC counts indicative, gastric analysis for absence or reduction of gastric acid; monthly intramuscular injections of B12 continued for life, adequate rest, mouth care; no cure, but early detection and treatment has good prognosis, no prevention

Idiopathic Thrombocytopenic Purpura

isolated deficiency of platelets from inhibition of production or destruction; inability of blood to clot, spontaneous hemorrhages in skin, internal organs, petechiae, ecchymoses; symptoms vary w/ age w/ more severing bleeding in older; bruising of unknown cause warrants screening; idiopathic = unknown cause, but antibodies which reduce life of platelets found in most cases; often after viral infection and spleen destroying damaged platelets; Diagnosed after everything else is ruled out first; prolonged bleeding time and reduced platelet count indicative, w/ weird size/shape of platelets common; corticosteroids, intravenous immune globulin administered along with blood and vitamin K to improve clotting; splenectomy as last resort; low death rate, prevention unknown

Immune Neutropenia

Decreased # of circulating neutrophils due to production of antineutrophic antibodies; malaise, fatigue, weakness, fever, stomatitis, recurrent infections; infants w/ respiratory infections warrants screening; accelerated turnover of neutrophils, i.e. inc prod, inc. destruction by antineutrophil antibodies; neutropenia associated w/ infection, drug exposure, ITP, hemolytic anemia; isoimmune neutropenia is rare disorder from transplacental transfer of maternal IgG reacting w/ fetal neutrophils’ confirmed by reduced # of WBCs; infants need no treatment, all others require corticosteroids, immune globulin, G-CSF, and appropriate antibiotics; benign prognosis, esp for infants, prevention unknown

Goodpasture’s Syndrome

same as anti-GBM antibody disease; kidney disease charact. by presence of antibodies directed against antigen in GBM; acute glomerulonephritis, relatively acute renal failure w/ proteinuria anemia, hematuria; scanty urine or other indicators of acute renal failure warrants screening; antibodies cause complement-mediated tissue damage resulting in glomerulonephritis; detection of anti-GBM antibodies in serum of kidney definitive, done by ELISA, immunofluorescence, or renal biopsy; urinalysis for proteinuria also indicative; plasmapheresis to remove anti-GBM antibody and corticosteroids for 6-12 months, w/ hemodialysis/kidney transplant as last resort; prognosis varies w/ severity; prevention unknown

Connective Tissue

Essential part of all structures of body; fibrous, insoluble protein collagen fundamental; in autoimmune disorders here, immune system attacks collagen, often by malfunction of immune system or genetics; no cures for these diseases known

Lupus (SLE)

Chronic, inflammatory, charact. by unusual antibodies in blood; Systemic lupus erythematosus inflames/damages connective tissue anywhere in body, mainly in skin, joints, neurons, organs; fly rash (erythema) on face, fever, fatigue, rashes in other places; unknown cause; a butterfly rash on face, discoid skin lesions, photosensitivity, nasopharyngeal ulceration, polyarthritis w/o deformity, false-positive serologic test result, seizures/psychosis, pericarditis, any of these four indicates diagnosis; antiinflammatory drugs, aspirin, antimalarial medication, corticosteroids common treatments; improvement continues w/ length of treatment

Scleroderma

Chronic, progressive, charact. by sclerosis/hardening of skin, int organs; diffuse is symmetric thickening of skin in extremities, face, trunk; limited is confined to fingers + face; hardened skin feels tough, itches, induces Raynaud’s phenomenon; unknown etiology, more often in women btwn 30-50; Lab tests for Scl-70 + centromere antibodies supports diagnosis, along w/ blood tests, urinalysis; No treatment, but physical therapy helps w/ muscle strength; prognosis varies on region affected, prevention unknown

Sjogren’s Syndrome

Inflammation of glands resulting in dryness in affected areas; rheumatoid arthritis, xerostomia, keratoconjunctivitis sicca; dryness → difficulties talking, chewing, swallowing; dryness in eyes or oral cavity leads to diagnosis; unknown cause, likely genetic, more likely in families predisposed to autoimmune diseases; blood studies indicate low WBC, elevated ESR; inc fluid intake, oral sprays relieves dryness; prognosis depends on complications, prevention includes avoiding drying of tissues, monitoring for cancers

Rheumatoid Arthritis

Chronic, inflammatory, affecting joints → deformity/disability; much more common in men but very widespread, often 30s-40s; edema of synovial membranes around joints spreads inflammation to surrounding areas, destroying cartilage, deforming joints; if neck joints → paralysis by afflicting spinal cord; noticeable joint stiffness, tenderness, erythema, warmth in joints, more prone to fingers, wrists, ankles; cause unknown, but believed to be inherited or by infection; diagnosis first of other autoimmune diseases w/ family history, physicals, radiographic studies, blood tests, to make diagnosis; treatment of anti-inflammatory medications, rest, special exercises, NSAIDs, special splints to make daily activities easier, surgery to correct deformation as last resort; prognosis depends on adequacy of treatment as does prevention

Juvenile Rheumatoid Arthritis

Most common 2-5 yo; polarticular (many joints) and systemic onset w/ high fevers and rash (Still Disease), usually larger joints; temp fluctuations, poor appetite, sudden weight loss, stiffness, anemia, irritability, painful red eyes; any fever, rash, swelling, or stiffness warrants screening; cause unknown but likely heredity; blood tests for rheumatoid factor basis diagnosis, w/ lack of growth or delayed phys growth also indicative; same treatment as normal RA and has good prognosis w/ proper therapy

Ankylosing Spondylitis

Systemic, progressive, inflammatory, affecting spinal column; often in young men, affecting sacroiliac area of spine and adjacent soft tissue; morning low back pain and stiffness, weight loss, fatigue, diarrhea may be present, pain and tenderness at place of inflammation; women can have mild forms of disease; progression of disease can limit range of motion due to fusion/ankyosis of joints; eventually, spinal vertebrae become rigid and posture cannot move; back stiffness warrants screening, often being underdiagnosed due to commonness of symptoms; negative rheumatoid factor, mild ESR, x-ray findings basis diagnosis; cause unknown, but genetic basis lean; no cure, but relief of pain/swelling w/ antiinflammatory medication and analgesics used; exercises to m maintain good posture done w/ surgery last resort; prognosis varies w/ severity

Polymyositis

Inflammation of muscle fibers, often close to trunk/torso, resulting in severe weakness; periods of inc symptoms (flares/relapses) and dec symptoms (remissions) occur in waves; muscle weakness, onset gradual or rapid, soon loss of muscle power and atrophy; trouble swallowing, weakness lifting head, tender muscles, potentially a rash; diffuse muscle weakness warrants screening; unknown cause, but due to when WBC invade and injure muscles; muscular dystrophy, drug toxicity, thyroid disorder, infection warrants diagnosis, along w/ medical history, blood analysis for elevated CPK or creatinine phosphokinase; steroids to suppress inflammation used alongside exercise therapy to retain strength; prognosis good, prevention by intervention at first signs

Multiple Sclerosis

Inflammatory attacking CNS myelin sheath; prevents transmission of stimuli to brain/spinal cord → weakness in limbs, optic neuritis, loss of vision in one eye, diplopia, unsteady gait, vertigo, difficulty urinating/urinary tract infections, facial numbness, speech problems, fatigue; any sporadic symptoms warrants screening; unknown cause, likely inherited trait or unknown virus; risk of MS inc going south to north, more in white populations, rare in children; relapse-remission waves occurs, multiple types of MS below; diagnosis by above symptoms and ruling out other disorders; acute MS treated w/ corticosteroids; progressive versions of MS treated w/ immunosuppressive therapies; otherwise, muscle relaxants, vitamins, physical therapy, adequate rest/diet best; prognosis bad all around, but some good for early age females, no prevention known

Relapse-Remitting

Relapses followed by recovery w/ no progression of neurologic dysfunction btwn relapses

Primary Progressive

Disease progression has no remissions

Secondary Progressive

Disease begins as relapsing-remitting, but later becomes progressive w/ few remissions

Progressive Relapsing

Progressive disease from onset, w/ relapses and disease progression during periods btwn relapses

Myasthenia Gravis

Chronic, progressive, stemming from autoantibodies to acetylcholine receptors; charact by extreme muscle weakness w/o atrophy, progressive fatigue; gradual or sudden symptoms w/ symptoms most noticeable in face; drooping eyelids, diplopia, difficulty doing daily actions, degree of weakness varies by the moment; myasthenic crisis is sudden inability to swallow and respiratory distress can lead to mechanical ventilation necessitation; any of these symptoms could also be a stroke so presence warrants screening; mainly women 20-40 yo due to faulty transmission of nerve impulses to and from CNS; Tensilon test, an intravenous administration of short-acting acetylcholinesterase inhibitor, done to see if muscle strength improves as grounds for diagnosis; treatment depends on age and pregnancy status, restricted activity, liquid diet, anticholinesterase drugs initially until they become less effective, corticosteroids; spontaneous, unexplained remissions will occur, not great prognosis; unknown prevention methods

Vasculitis

Inflammation of walls of blood vessels, leading to them becoming necrotic when obstructed w/ thrombus; any and all vessels can be a target; two types

Small Vessel Vasculitis

Capillaries, arterioles, venules primarily; Causes petechiae, purpura, erythema, ulcerations, edema on skin and lower extremities; pain/burning sensation can accompany these lesions; often accompanies other immune disorders, so exposure to certain chemicals, foreign proteins, drugs, foods, or infections could be causes; histology and immunofluorescence studies of biopsied tissue grounds diagnosis; identification of causative agents and consistent therapy is treatment, e.g. corticosteroid therapy or analgesic; prognosis very good, meds prevents

Systemic Necrotizing Vasculitis

Medium/Large arteries; symptoms vary w/ body system involved, e.g. headaches, fever, weakness, weight loss, joint pain, hypertension, ischemic pain; etiology varies, w/ some forms clearly related to amphetamine use, hepatitis B/C; complete history, CBC, ESR serum tests; CBC indicates anemia, elevated WBC, grounds diagnosis; treatment focus on dec inflammation, identifying underlying causes and treating accordingly, e.g. corticosteroids, analgesics, immune suppressives; prognosis guarded until controlled by meds, no prevention known