18 results
Diagnosis and Management of Hypocomplementemic Urticarial Vasculitis (HUV)

Diagnosis of HUV
1) Chronic urticaria 
2) Leukocytoclastic vasculitis 
3)
Diagnosis and Management ... of Hypocomplementemic ... (HUV) Diagnosis ... 3) Hypocomplementemia ... TerrierBen #Hypocomplementemic
Pathophysiology of Hypocomplementemic Urticarial Vasculitis

C1q/anti-C1q antibiody ->
Immune Complex Formation - Complement Pathway Activation (C3a and C5a)
Pathophysiology of Hypocomplementemic ... Urticarial Vasculitis ... Complex Formation - Complement ... TerrierBen #Hypocomplementemic ... #HUV #Pathophysiology
Causes of Hypocomplementemia - CHAMPS Mnemonic
C - Cryoglobulinemia (85%), C3 glomerulopathy, cirrhosis
H - Heavy Chain deposition
Causes of Hypocomplementemia ... A - Atypical HUS ... @AnnKumfer #Hypocomplementemia ... #Low #Complement
Vasculitis and Vasculitides - Differential Diagnosis Framework

When to Consider Vasculitis:
 • Purpura, ischemic skin lesions
 •
often involved • Hypocomplementemic ... Urticaria and hypocomplementemia ... against MPO • Complement ... (Low levels mixed ... • HBV HCV •
Pulmonary Renal Syndromes and Mimics - Differential Diagnosis Framework
Diffuse alveolar hemorrhage + rapidly progressive glomerulonephritis
90%:
 -
ANCA Associated Vasculitis ... anti-GBM) 10%: - Low ... Complement Levels ... - Normal Complement ... , atypical HUS,
Rapidly Progressive Glomerulonephritis (RPGN)
RPGN has three primary pathophysiologic causes differentiated by immunofluorescence

Immune Complex Mediated (granular staining):
staining): • Low ... Complement: Post-strep ... Idiopathic • Normal Complement ... Glomerulonephritis #Vasculitis ... differential #diagnosis #algorithm
Vasculitis - Differential Diagnosis Framework

When to Consider Vasculitis:
• Purpura, ischemic skin lesions
• Mononeuritis multiplex
• Hematuria, proteinuria,
Vasculitis - Differential ... When to Consider Vasculitis ... HTN • Check: HBV ... Elevated AST ALT • Hypocomplementemia ... ) • Hypocomplementemic
Cryoglobulinemia Summary

Cryoglobulins:
 • Cryoglobulins are Igs in the serum that precipitate in vitro at temperatures below
• Infections: HCV ... infection, HBV ... infection, HIV infection ... factor level • Low ... serum C4 complement
IgG4-Related Disease
Clinical history:  Man, 60 years, multiorgan involvement, unique or multiple inflammatory pseudotumor
4 phenotypes:
 •
rheumatoid factor), ± hypocomplementemia ... No necrosis, No vasculitis ... Disease #diagnosis #management
The algorithm below shows how pre-test probability could be combined with various criteria to determine which
The algorithm below ... shows how pre-test ... acyclovir: This algorithm ... patient with a low ... is proposed: #Management