15 results
Summary table of types of hypersensitivity reactions. 
Type 1
 - Mediators: lgE
 - Antigen Form: Soluble
table of types of hypersensitivity ... Allergen-specific lgE causes ... Anaphylaxis, Hay fever ... they activate complement ... allergy #table #classification
ID Approach to Fever and Rash - Diagnostic Algorithm
Central Maculopapular (most common):
Measles, Parvovirus 819 / EBV,
ID Approach to Fever ... Rash - Diagnostic Algorithm ... Secondary syphilis, EM ... Parvovirus B19 (PPGSS), Vasculitis ... Febrile #Diagnosis #Algorithm
Rapidly Progressive Glomerulonephritis (RPGN)
RPGN has three primary pathophysiologic causes differentiated by immunofluorescence

Immune Complex Mediated (granular staining):
pathophysiologic causes ... staining): • Low Complement ... Idiopathic • Normal Complement ... Glomerulonephritis #Vasculitis ... differential #diagnosis #algorithm
Hypersensitivity Types and Their Mechanisms
Type I - lgE - Soluble antigen
 - Allergen-specific lgE antibodies bind
Hypersensitivity ... , seasonal hay fever ... antigen, leading to complement ... Complement activation ... #Types #Classification
Vasculitis and Vasculitides - Differential Diagnosis Framework

When to Consider Vasculitis:
 • Purpura, ischemic skin lesions
 •
tract, and often causes ... Coronary arteries - Fever ... : • Fevers • ... against MPO • Complement ... #rheumatology #classification
Cryoglobulinemia Summary

Cryoglobulins:
 • Cryoglobulins are Igs in the serum that precipitate in vitro at temperatures below
• They can cause ... Cryoglobulins Cause ... • Low serum C4 complement ... • Hypersensitivity ... diagnosis #types #classification
Purpura - Differential Diagnosis Framework

Non-blanchable, dark red to purple, hemorrhagic skin lesions that result from leakage
disorders, or other causes ... • Secondary Causes ... : • Hypersensitivity ... • Ig A vasculitis ... mountain spotted fever
Serious Bacterial Illness (SBI):
1) UTI and pyelonephritis
Most common cause of SBI
Accounts for 3-8% of uncharacterized fevers
Female
pyelonephritis Most common cause ... uncharacterized fevers ... Diagnosis #Peds #EM ... #Classification ... #Fever #SBI #SeriousBacterialIllness
Causes of Petechial Rash - Differential Diagnosis Algorithm

Pinpoint areas (less than 2 mm) of hemorrhage, which
Causes of Petechial ... Differential Diagnosis Algorithm ... Infection - Vasculitis ... Red Flags: • Fever ... #Causes #dermatology
Vasculitis - Differential Diagnosis Framework

When to Consider Vasculitis:
• Purpura, ischemic skin lesions
• Mononeuritis multiplex
• Hematuria, proteinuria,
: • Fevers • Fatigue ... and branches • Fever ... Coronary arteries • Fever ... tract, and often causes ... inflammation Hypersensitivity