Autoimmune hemolytic anemia (AIHA) is characterised by the premature destruction of erythrocytes, which is mediated by autoantibodies and complement system activation. This condition is rare condition, with an estimated incidence rate of 1.4/100,000 individuals/year. Anemia manifests in two distinct forms: - warm (IgG), responsible for approximately 70% of cases; - cold (IgM/complement), representing up to 20%; - mixed (IgM + IgG), approximately 10%. The diagnosis is generally made by means of the identification of immunoglobulin G and/or complement (C3d) on the erythrocyte surface. This is achieved by conducting a direct antiglobulin test (DAT).

To describe the sociodemographic profile of AHAI patients who were treated at the Amazonas Hematology and Hemotherapy Foundation (HEMOAM).

This analysis was informed by retrospective study using data extracted from the IDoctor electronic health record system from HEMOAM, employing the ICD-D59.1 code, encompassing the period from January/2015 to January/2025. The diagnostic confirmation was performed by means of an analysis of the DAT results, which were accessed on the SoftLab/HEMOAM laboratory platform.

A total of 62 patients with AIHA were identified, with ages ranging from 20 to 88 years (50.9 ±18.5 years) and a predominance of women (74.2%). As expected, the majority of patients resided in the city of Manaus, constituting 77.4% of cases. With respect to ethnicity, 76.9% of patients self-declared as brown, 12.8% as white, 5.1% as black, and 5.1% as indigenous.

Discussion: Despite the evidence of a considerable age disparity within the study population, the mean age of subjects aligns with the findings of related national research, which indicates a heightened prevalence of AIHA among middle-aged and elderly adults. As demonstrated in earlier studies undertaken in Denmark, there is a predominance among the female sex. This pattern is also evident in the Amazonian population, where the number of cases observed in women is significantly higher than in men. The notable presence of individuals who self-identify as "brown" reflects the predominant ethnic composition of the region. Conclusion: Autoimmune hemolytic anaemia is a heterogeneous and complex disease that affects wide regions worldwide. The findings demonstrate that this disease in adults has a broad age distribution, and the predominance of brown ethnicity reflects the local population composition. The sociodemographic characterization clearly conducive to a more profound comprehension of the profile of affected patients. Moreover, it reinforces the importance of adequate completion of clinical-epidemiological data. This is because it guides diagnostic and therapeutic strategies, as well as future investigations into susceptibility in AIHA.