Israel Medical Association Journal

Intussuception is the most common cause of intestinal obstruction in early childhood. The cause of most intussusceptions is unknown but it can complicate the course of Henoch-Schonlein purpura (HSP) as a result of the vasculitic process. Familial Mediterranean fever (FMF), a most common disease in Israel is also associated with HSP. In a few patients, particularly in children, HSP has been reported to precede the diagnosis of FMF. We describe two patients with an unusual clinical course of severe abdominal pain as a result of intusucception. The correlation between intusucception, HSP and FMF are discussed.
 

Treatment of vasculitides has progressed markedly over the past few decades. Recent therapeutic strategies in severe and refractory anti-neutrophil cytoplasmic antibodies-associated vasculitides include immunomodulating methods (e.g., plasma exchanges), products (such as intravenous immunoglobulins) and, more recently, new agents called biotherapies. Some of them (e.g., anti-tumor necrosis factor-alpha and anti-CD20 monoclonal antibodies) have achieved promising results and are now often used to treat severe cases.

Objectives: To help clinicians and laboratory scientists recognize and utilize vasculitis-related ANCAs as an aid in diagnostic workup and patient follow-up, and be aware that ANCAs with different characteristics are commonly found in other chronic inflammatory conditions that persistently engage neutrophils in the inflammatory process.

Methods: Indirect immunofluorescence and enzyme immunoassay methods were used to detect ANCAs with both known and unknown neutrophil autoantigenic targets.

Results: Primary necrotizing small vessel vasculitides such as Wegener’s granulomatosis, Churg-Strauss syndrome, microscopic polyangiitis, and renal-limited rapidly progressive necrotizing glomerulonephritis target either the serine protease proteinase 3 or myeloperoxidase  in azurophilic granules. In ulcerative colitis and rheumatoid arthritis, we found multiple ANCA targets contained in azurophilic and specific granules, the cytosol and the nucleus, whereas PR3² and MPO³ were not, or only weakly, recognized.

Conclusions: ANCAs typically found in active SVV⁴ are demonstrable both by indirect immunofluorescence and antigen-specific enzyme immunoassay, and strong reactivity to either PR3 or MPO is characteristic. Strong ANCA with MPO reactivity is also found in some patients with drug-induced syndromes (lupus, vasculitis). Intermediate to strong perinuclear ANCAs are found in a substantial proportion of patients with UC⁵ (40–60%) and RA⁶ (30–70%), but in these conditions the ANCAs have many antigen targets that are only weakly recognized.

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¹ ANCA = anti-neutrophil cytoplasm antibody

² PR3 = protease proteinase 3

³ MPO = myeloperoxidase

⁴ SVV = small vessel vasculitides

⁵ UC = ulcerative colitis

⁶ RA = rheumatoid arthritis