Objective To determine the overall prevalence of autoimmune hemolytic anemia 
(AIHA), and to compare clinical and laboratory features in a large population of 
children and adult lupus patients at diagnosis. Methods This retrospective study 
evaluated the medical charts of 336 childhood-onset systemic lupus erythematosus 
(cSLE) and 1830 adult SLE (aSLE) patients followed in the same tertiary 
hospital. Demographic data, clinical features and disease activity were 
recorded. AIHA was defined according to the presence of anemia (hemoglobin 
<10 g/dL) and evidence of hemolysis (reticulocytosis and positive direct 
antiglobulin test (DAT)/Coombs test) at SLE diagnosis. Evans syndrome (ES) was 
defined by the combination of immune thrombocytopenia (platelet count 
<100,000/mm3) and AIHA. Results The frequency of AIHA at diagnosis was 
significantly higher in cSLE patients compared to aSLE (49/336 (14%) vs 49/1830 
(3%), p = 0.0001), with similar frequency of ES (3/336 (0.9%) vs 10/1830 (0.5%), 
p = 0.438). The median of hemoglobin levels was reduced in cSLE vs aSLE patients 
(8.3 (2.2-10) vs 9.5 (6.6-10) g/dL, p = 0.002) with a higher frequency of 
multiple hemorrhagic manifestations (41% vs 7%, p = 0.041) and erythrocyte 
transfusion due to bleeding (24% vs 5%, p = 0.025). cSLE patients also had more 
often constitutional involvement (84% vs 31%, p < 0.001), fever (65% vs 26%, 
p < 0.001), weight loss > 2 kg (39% vs 6%, p < 0.001), reticuloendothelial 
manifestations (48% vs 8%, p < 0.001), hepatomegaly (25% vs 2%, p < 0.001) and 
splenomegaly (21% vs 2%, p = 0.004). Other major organ involvements were common 
but with similar frequencies in cSLE and aSLE ( p > 0.05). Median systemic lupus 
erythematosus disease activity index 2000 (SLEDAI-2 K) was comparable in cSLE 
and aSLE (p = 0.161). Conclusions We identified that AIHA was not a common 
condition in cSLE and aSLE, with distinct features characterized by a higher 
prevalence/severity in children and concomitant constitutional symptoms in the 
majority of them.