Clinical Medicine: Intro to Allergic Disease Flashcards
(119 cards)
Etiology of anaphylaxis
IgE mediated. Caused by: 1. food 2. Pollen 3. Insect stings (venom) 4. Latex 5. Drugs Nonimmunolgic: (mast cell degranulation, but not IgE mediated) 1. Exercise 2. Cold 3. Heat (sunlight/UV)
Clinical presentation of anaphylaxis (5-30min)
- CNS - lightheadedness, LOC, confusion, headache, anxiety
- Resp - SOB, Wheezes, pain with swallowing, cough, bronchodilation.
- GI - Cramping, diarrhea, vomitting
- Skin - hives, itchiness, flushing (90% of pts)
- Vascular - Hypotension, swelling, smooth muscle contraction
- Eyes - Swelling of conjuctiva
Category of RXN of anaphylaxis
Type I
Etiology of autoimmune hemolytic anemia
1/2 of cases idiopathic
- may also be associated with systemic lupus erythematous
Chronic lymphocytic leukemia
lymphomas. Caused by antibody induced hemolysis (destruction of RBCs) IgG or IgM mediated
Clinical presentation of hemolytic anemia
- May be asymptomatic
- Life threatening
- Looks like other anemias
- Fatigue, dyspnea
- Angina or HF
- Jaundice and splenomegaly may be present
Category of RXN of hemolytic anemia
Type II
Etiology of post streptococcal glomerulonephritis (PSGN)
Caused by prior infection with group A beta-hemolytic streptococcus (immune complex hypersensitivity). Complexes get trapped in glomeruli that causes an inflammatory reaction.
Who presents with PSGN most commonly
2-6yo with hx of pharyngitis(cold climate) and rash-impetigo (warm climate)
Clinical presentation of PSGN
- Most children asymptomatic
- Headache, malaise
- Anorexia, nausea, vomiting
- Flank/back pain - red urine
- Oligouria
- Elevated BP/edema
Category of RXN of PSGN
Type III
Etiology of serum sickness
Caused by antitoxins, antivenins, streptokinase, vaccines, insects. This then induces an antibody response and the formation of an immune complex. Causes tissue damage and vasculitis
Clinical presentation of serum sickness
- Pruritic rash - maculopapular or urticarial (hives)
- High fever
- polyarthritis
Begins 7-10 days after exposure
Usually goes away but could progress to angioedema, nephritis
Category of RXN of serum sickness
Type III
Etiology of vasculitis
Immune complexes are trapped in vessel walls. Leads to vessel injury. Primary - unknown cause. Secondary - infectious cause
Clinical presentation of vasculitis
- Fever, night sweats
- Fatigue, anorexia, weight loss
- Arthalgia/arthritis
- alveolar hemorrhage
- Mesenteric ischemia
(some skin lesions - Palpable purpura - small vessels
Category of RXN of vasculitis
Type III
Types of vasculitis (classification)
- Small vessel - Henoch-schonlein
- Medium vessel - kawasaki disease
- Large vessel - Giant cell temporal arteritis
Etiology of contact dermatitis
- Sensitization to an antigen
- Allergic response after reexposure
Many causes - see chart in lecture notes pg 27
Clinical presentation of contact dermatitis
Primary = intense pruritis 1. Transient erythema 2. vesiculations 3. Excoriation/infection 4. Swelling with bullae Most common site is hands
Category of RXN of contact dermatitis
Type IV
Etiology of transplant rejection
Graft destruction caused by T cell-mediated reaction to allograft histocompatibility antigens
Clinical presentation of transplant rejection
Seen within days-few months post transplant
- Fever/chills
- Malaise
- Arthralgias
Category of RXN of transplant rejection
Type IV
What is the difference between anaphylaxis and anaphylactoid
- Anaphylaxis is mediated by IgE where as anaphylactoid is not
- Anaphylactoid can occur at 1st exposure, anaphylaxis cannot
- Skin test can only predict allergy in anaphylaxis