[Clinical analysis of 12 patients with pediatric antiphospholipid syndrome with pulmonary embolism].

Objective: To identify the clinical and immunological characteristics of pediatric antiphospholipid syndrome (APS) patients with pulmonary embolism. Method: Among 47 pediatric APS patients from Peking Union Medical College Hospital during the year of 2000 to 2015, 12 patients were diagnosed of pulmonary embolism, who were investigated and compared with APS patients without pulmonary embolism. Result: Twelve patients (among whom 6 cases were primary and the other 6 were secondary APS)had pulmonary embolism and all of them were non-shock type, which was the first presenting manifestation in 6 of them.Eight cases were misdiagnosed as infection, while 3 cases were missed.Among patients with pulmonary embolism, 10 patients suffered from deep vein thrombosis at the same time, mainly in lower extremities.2 cases had thrombotic recurrence, which happened only in primary APS patients, because of irregular monitoring of International Normalized Ratio, or not taking aspirin after quitting warfarin.Positive anticardiolipin (ACL) and lupus anticoagulant (LA) were found in 10 and 9 patients respectively.Four primary APS patients had positive anti-nuclear antibodies (ANA). During follow-up of 3-100 months (median 23 months) of primary APS, no one had evolved manifestations of systemic lupus erythematosus.Primary APS was more often seen in males (M∶F 5∶1 vs . 0∶6) and the patients were much younger ((15±1) vs . (17±0) years old) than those with secondary APS.Besides that, no statistically significant difference was seen between primary and secondary APS ( P all>0.05). Compared with APS patients without pulmonary embolism, pulmonary hypertension was more common in patients suffered from pulmonary embolism (3/12 vs . 0, P <0.05). Conclusion: Pulmonary embolism can be the first symptom in pediatric APS patients and all of them are non-shock type, which tends to be misdiagnosed or missed. A majority of them suffer from deep vein thrombosis in the lower extremities.Rethrombosis takes place when the anticoagulant therapy is irregular.Positive anti-nuclear antibodies can be seen in primary APS patients, but no manifestations of lupus come out during follow-up.There is no significant difference between primary APS and secondary APS.Pulmonary hypertension is more common in APS patients suffered from pulmonary embolism.