[Acquired C1 inhibitor deficiency associated with lymphoproliferative disorders: four cases]. / Déficit acquis en C1 inhibiteur associé à un syndrome lymphoprolifératif: quatre observations.

INTRODUCTION: Acquired C1 inhibitor deficiency is sometimes associated with lymphoproliferative disorders. EXEGESIS: We report four cases of acquired C1 inhibitor deficiency in association with lymphoproliferative disorders. Three of them were asymptomatic; one was associated with abdominal pain. Four women (median age, 66 years) presented either two non-Hodgkin lymphoma or two chronic lymphocytic leukaemia. C1 inhibitor deficiency was detected fortuitous (n = 1) or during investigation of arthralgia (n = 2), or Gougerot-Sjogren syndrome (n = 1). The deficit was acquired in all cases type I. Auto-immune disorders were associated with: Gougerot-Sjogren syndrome (n = 1), cryoglobulinemia (n = 2), IgM lambda monoclonal gammopathy (n = 1), Coombs positive test (n = 2), IgG anti-cardiolipine antibodies (n = 1). C1 inhibitor deficiency was not modified after lymphoproliferative disorders treatment (radiotherapy, splenic ablation) in two cases but patients were not in complete remission. C1 inhibitor raised normal level in one case, after five chemotherapy regimens, but decreased complement level and C4 split persist. CONCLUSION: Acquired C1 inhibitor deficiency associated with lymphoproliferative disorders is sometimes asymptomatic. Diagnosis could be delay in spite of clinical manifestations. Deficit correction is not constant after lymphoproliferative disorders treatment.