Evans Syndrome: A Systematic Review

Introduction:

Evans syndrome is a rare autoimmune disease that consists of autoimmune hemolytic anemia (AIHA) and immune thrombocytopenia(ITP) with or without neutropenia. Evans syndrome can be classified as primary(idiopathic) vs secondary (presence of underlying causes). The presence of AIHA and ITP might not occur concomitantly and might precede one another. Treatment options in evans syndrome are variable but mostly involves corticosteroid, rituximab and splenectomy in refractory cases.

Methods:

Two independent investigators searched databases PUBMED, MEDLINE, EMBASE with key word “evans syndrome” and included articles containing 5 or more cases of Evans syndrome in adults, excluding articles on pregnant , infants and children. Further data about patient characteristics, clinical features and treatment were extracted for analysis.

Results:

10 studies (9 retrospective and 1 prospective studies) fulfilled our inclusion criteria.The number of female patients was 52.2% (275/527) vs 47.8% (252/527) male patients. Among them 68.4%(335/490) had primary Evans syndrome compared to 31.6%(155/490) had secondary evans syndrome due to underlying causes. ITP and AIHA occurred simultaneously in 52.4%(276/527) cases, ITP before AIHA in 34.2%(180/527) cases, AIHA before ITP in 23.1%(122/527) cases. Among the patients with positive Direct Antiglobulin Test(DAT), 46.6%(116/249) had positive IgG , 33.3%(83/249) had positive IgG +C3d and 6.4%(16/249) had positive C3d . Only 6 studies had data on neutropenia that was present in 8.2% (18/219) cases. All patients were treated with corticosteroids, 18.4% (47/256) were received rituximab and 16.3%(76/466) refractory cases received splenectomy. We had mortality data from six studies which showed that 40.87% (188/460) cases had died.

Conclusion:

Our review showed that the clinical presentation of Evans syndrome can be variable and quite challenging. Most cases are primary Evans syndrome however looking for underlying causes in secondary Evans syndrome and other differentials is also important. Evans syndrome though rare has high mortality.

No relevant conflicts of interest to declare.