Severe haematological involvement in children with systemic lupus erythematosus and clinical associations

Rheumatology (Oxford). 2024 Aug 2:keae414. doi: 10.1093/rheumatology/keae414. Online ahead of print.

Abstract

Objectives: To investigate the severe haematological involvement in children with SLE and assess its clinical associations, treatments, outcome and damage accrual.

Methods: The medical charts of children with SLE in whom haematological involvement was observed were reviewed. Severe haematological indices were defined as autoimmune haemolytic anaemia with a haemoglobin concentration < 8 g/dL, thrombocyte count < 30 000/µL, and neutrophil count < 500/µL.

Results: Among the 224 patients included, 102 (45.5%) displayed severe indices, predominantly at the initial involvement, and most frequently as severe anaemia in 54 (24.1%) and severe thrombocytopenia in 45 (20.1%). Disease activity did not differ according to the presence of severe disease indices. In addition, the presence of severe indices at initial involvement did not affect the damage accrual. However, a higher rate of damage (51.1% vs. 29.9%, p = 0.002) and steroid-induced damage (28.9% vs. 8.2%, p < 0.001) was evident in patients with flares of the haematological system. Regression analysis revealed that rituximab treatment during the initial episode (OR:4.5, p = 0.006) and the presence of anticardiolipin antibodies (OR:2.3, p = 0.014) significantly increases the odds for haematological system flare. However, severe indices at initial involvement did not increase the odds of a haematological flare.

Conclusion: Severe haematological indices at onset are common but not related with disease outcomes. Prevention of flares is important to improve outcomes, and a more rigorous maintenance strategy would benefit most to children who display haematological indices refractory to conventional immunosuppressants and those with anti-cardiolipin antibodies.

Keywords: children; damage; flare; haematological involvement; systemic lupus erythematosus; treatment.