Background Long-term outcome data of Anti-Phospholipid syndrome (APLS) in paediatric patient population is very limited. There are no established criteria for making a diagnosis of Paediatric Anti- Phospholipid syndrome (APLS). Adult APLS criteria includes the major criteria of fetal loss, which is not pertinent to the pedriatric population.

Objectives To evaluate the clinical outcome of paediatric patients who either had a positive Lupus Anticoagulant (LAC), moderately high titer of anti-cardiolipin antibodies (ACLA) or anti-b₂ glycoprotein-1 antibodies on more than one occasion.

Methods We identified 19 patients (17 females, 2 males), mean age of disease onset was 11.7 years (range 7–16 years). Patients were followed-up a median of 96 months (range 12–204 months).

Results Seven patients had only IgG ACLA, one had only IgM ACLA, two had both IgG and IgM ACLA, one had IgG and IgA ACLA, and one had all three ACLA’s present. One patient had significantly positive LAC and IgM ACLA and four patients had positive results for both anti-β 2 glycoprotein and ACLA. Out of 17 patients, 11 had a diagnosis of Systemic Lupus Erythematosus (SLE) and 6 patients did not have any other connective tissue disease (CTD) diagnosis. On clinical presentation, 4 patients had headaches (HA), 4 had livedo reticularis, and 8 had both HA and livedo reticularis. At initial presentation, 1 patient had venous thrombosis, 1 had chorea nad one had both arterial and venous thrombosis with no previous CTD diagnosis. One patient with SLE presented with arterial thrombosis. In the follow-up period, one patient had a miscarriage and chose not to become pregnant again. All patients were placed on low-dose aspirin (ASA) [81 mg/d] and hrdroxychloroquine (HCQ) if they had a diagnosis of SLE. Patients who had an event at presentation were treated with warfarin for 6 months and then switched to ASA alone after 6 months. There were no events noted in patients who were treated after their initial presentation to our clinic.

Conclusion This long-term follow-up shows that: 1) Livedo reticularis and HA are common initial presentations of APLS, but, 2) Prognosis has been very good with treatment with ASA and HCQ in the paediatric APLS group.