Immunoglobulin A vasculitis (IgA-V), formerly called Henoch-Schönlein purpura, is an immune vasculitis. Relapses are frequent (30%) and most of the time cutaneous (90%). Cutaneous involvement in adults is more severe (haemorrhagic blister or necrotic skin lesions) and more extensive than in children. Quality of life can be significantly altered by frequent cutaneous relapses. Colchicine, historically used for gout flares, is known to be an " old " low cost drug inducing very few adverse events. This molecule inhibits polymorphonuclear cell-chemotaxis to the site of inflammation explaining colchicine clinical efficacy in diseases such as Familial Mediterranean Fever or Behçet disease. Efficacy of colchicine has also been reported in cutaneous leukocytoclastic vasculitis including IgA-V, but without clinical studies supporting this attitude.

Immunoglobulin A vasculitis (IgA-V), formerly called Henoch-Schönlein purpura, is an immune vasculitis. Relapses are frequent (30%) and most of the time cutaneous (90%). Cutaneous involvement in adults is more severe (haemorrhagic blister or necrotic skin lesions) and more extensive than in children. Quality of life can be significantly altered by frequent cutaneous relapses. Colchicine, historically used for gout flares, is known to be an " old " low cost drug inducing very few adverse events. It inhibits polymorphonuclear cell-chemotaxis to the site of inflammation explaining colchicine clinical efficacy in diseases such as Familial Mediterranean Fever or Behçet disease. Efficacy of colchicine has also been reported in cutaneous leukocytoclastic vasculitis including IgA-V, but without clinical studies supporting this attitude To assess efficacy of colchicine in adult's cutaneous IgA-V, the investigators conduct a prospective, controlled, double blind, randomized clinical trial, national, multicenter and multidisciplinary (internal medicine, nephrology and dermatology): colchicine 1mg/day versus placebo for 6 months, with a 12 months total follow-up. The primary objective is to evaluate efficacy of colchicine versus placebo to prevent cutaneous relapses, 6 months after inclusion, in adult patients with cutaneous IgA vasculitis alone or associated with non-severe digestive or renal involvement.

Inclusion Criteria:

1. Age ≥ 18 years and < 85 years

2. IgA-V recently diagnosed (< 20 days since skin biopsy) and defined by :

   • Histologically proven small vessels vasculitis with IgA deposits IgA Vasculitis
   • Purpura and/or involvement of at least one organ among kidney, joint, or intestinal tract

Exclusion Criteria:

1. Severe renal IgA vasculitis:

   • impaired renal function, defined as an eGFR < 60 ml per minute per 1.73 m2 (MDRD or CKD-EPI formula)
   • proteinuria/creatinuria> 1g/g
   • Uncontrolled blood pressure (Systolic blood pressure > 170 mmHg, diastolic blood pressure > 100 mmHg)

2. Severe digestive IgA vasculitis:

   • intussusception
   • massive gastrointestinal haemorrhage (requiring transfusion)
   • intestinal ischemia
   • perforation
   • abdominal pain persisting more than one day (EVA > 5) and unresponsive to standard analgesics (level 1 or 2).

3. Prior (< 3 months) immunosuppressive or corticosteroid therapy

4. Additional cutaneous, and/or digestive and/or chronic renal diseases.

5. HIV and B and C Chronic hepatitis

6. Pregnancy or breast feeding or women without sufficient contraception among women of childbearing

7. Known allergy or intolerance to study medication or any of its excipients (lactose, saccharose)

8. Contraindication to colchicine such as:

   • severe hepatic insufficiency
   • combination with a macrolide (except spiramycin),
   • combination with pristinamycin

9. Participation in another interventional trial

10. Patient having not signed an informed consent

11. Patient without Social Security System Insurance