Warm autoimmune hemolytic anemia in adults in Latin America: A scoping review

Autoimmune hemolytic anemia is a rare disorder characterized by the autoimmune-mediated destruction of red blood cells. The condition is classified into subtypes based on the thermal reactivity of the autoantibodies, with warm autoimmune hemolytic anemia representing the most common form in adults. This review aimed to summarize the clinical evidence regarding warm autoimmune hemolytic anemia generated in adult patients within the Latin American region.

A literature search was conducted in Embase, Medline, Lilacs, Cochrane Library, Epistemonikos, and Value in Health in April 2023. Gray literature was also consulted. Records were eligible for inclusion if they presented data on the epidemiology, diagnosis, treatment, or healthcare resource utilization among adult warm autoimmune hemolytic anemia patients in Latin American countries. Clinical practice guidelines on the condition issued in Latin American were also eligible.

Nine records were included: seven retrospective studies (six single-center), one national clinical guidelines (Mexico), and one therapeutic protocol (Brazil). Corticosteroids are the cornerstone of first-line treatment, reported in 97.7 % of 354 patients enrolled in the studies, primarily as monotherapy (91 %). While response rates were high (69-84 %), a considerable proportion of patients (15-40 %) required second-line therapies. The use of splenectomy varied widely between studies, from being the preferred second-line option to not being performed in any patient. Access barriers contribute to a limited use of rituximab.

Compared to other hemolytic disorders, warm autoimmune hemolytic anemia studies are lacking in Latin American and consist primarily of single-center, retrospective case series. Further research is warranted to understand management strategies in refractory disease.