The prevalence of Lupus Anticoagulant in Iranian children and adolescents; Current status and literature review of diagnosis

Background: lupus anticoagulant (lac) is an acquired igg or igm autoimmune antibody against platelet membrane phospholipids. lac is an important cause of aptt prolongation in children. we determined the prevalence of la-positive results in ≤ 18 years patients referred to the iranian blood transfusion organization (ibto) special reference coagulation laboratory.method: during a period of 27 months all patients ≤ 18 years old who were referred to ibto and had results of aptt and lac were evaluated. lac test panel included screening tests (aptt-la and drvvt screen) and the mixing test and confirmatory tests (hexagonal assay and/or drvvt confirm) all performed by stago reagents and instruments. in cases with positive lac, their follow-up refers to ibto coagulation lab were evaluated after 12 weeks.results: our data revealed a lac prevalence of 2.4% in the referred patients ≤ 18 years who had aptt test result and 31% in those whom the lac test was performed for them. in more than half of the la-positive patients, the main reason for referring was an incidental finding of aptt prolongation noticed before surgery or during hospitalization. interestingly only 21.6% of the patients with positive lac results were requested by the physician.conclusions: lac is not infrequent in children and adolescents however in most cases it is a transient problem without any significant clinical findings. most of the cases (78.4%) were not suspected of lac by their physicians so it may be frequently missed in children clinically.