A 40 y.o. male presents with GI bleeding and a rash.

What do you think is wrong?

Hint: the purpura are palpable

Our patient had a small vessel vasculitis.  This was not an IgA vasculitis such as is seen in Henoch Schonlein purpura in children.

 So what other kinds of small vessel vasculitis are there?

There are two major categories of small –vessel vasculitis: ANCA-associated vasculitis and immune complex-mediated vasculitis.

ANCA-ASSOCIATED VASCULITIS( antineutrophil cytoplasmic antibody)

Wegener’s involves the upper airways and may result in “saddle nose”

1. . Wegener’s or granulomatosis with polyangiitis- is a small vessel vasculitis involving the upper airways and lungs.  The      kidneys may also be involved.

2.       Microscopic polyangiitis

3.       Eosinophilic granulomatosis with polyangiitis  (Churg Strauss)- Asthma is the most common sign of Churg-Strauss syndrome

Antineutrophil cytoplasmic antibodies were first  recognized when sera from patients with vasculitis were noted to bind to neutrophils in vitro in two patterns.  One antibody was perinuclear (p-ANCA) and the other was diffuse throughout the cytoplasm (c-ANCA) .  ANCA associated diseases are associated with one or the other of these antibodies. P-ANCA is directed at myeloperoxidase(MPO) and c-ANCA directed at a neutrophil protease(PR3).  Often the extent of ANCA deposition is not extensive  and little antibody staining is seen.

Wegeners has c-ANCA and PR3 positivity

Microscopic polyangiitis  has p-ANCA and anti-MPO antibodies

Eosinophilic granulomatosis with polyangiitis  is rare .  IgE is elevated and p-ANCA/anti MPO pattern is seen.

Churg Strauss may present with necrotic nodules or hemorrhage which appears as “ground glass” on CT.

IMMUNE COMPLEX-MEDIATED VASCULITIS- typically presents with palpable pupura in the lower extremities. These types of vasculitis are associated with complement activation

1.       Cryoglobulinemic vasculitis- the antibodies formed are common in hep C, malignancies and autoimmune disease. The antibodies are  often polyclonal IgG. In mixed cryoglobulinemia they can also be IgM or  Cryoglobulins can cause hyperviscosity requiring plasmapheresis.

2.       Henoch-Schonlein Purpura- is the most common childhood vasculitis. It is  associated with IgA antibodies. It is usually is self-limiting. The kidneys and GI tract may be involved.

3.       Hypersensitivity vasculitis-  is a hypersensitivity response to a drug or infection.

cryoglobulinemia from Hep C

Our patient had crypt abscesses on colonoscopy and was treated with prednisone. All other testing was negative.

Ratzinger G, Zelger B, Carlson J, et al. Vasculitic wheel-aan algorithmic approach to cutaneous vaculitides. J Dtsch Dermatol Ges 2015;13:1092-117.

Crowson A, Mihm M, Magro C. Cutaneous vasculitis: a review. J Cutan Pathol 2003;30:161-73.

ACP MKSAP 17. Rheumatology 73-75.  Illustrations are taken from there.

Fernandes G, Teixeira A, Anton A. et al Churg-Strauss syndrome: a case report.  Badio Bras. 2014 Jul-Aug 47(4):259-261

….and for the curious if you always wanted to know the mechanisms of small vessel vasculitis……..

Wegener’s

Immune complex vasculitis