We describe a previously healthy 9-year-old girl who had multiple
purpura several days after acute adenovirus
gastroenteritis and
mycoplasma pneumonia. Initial laboratory evaluation revealed a prolonged prothrombin time (PT) and APTT, low
complement levels (C4, CH50), and positive
immune complex (C1q) in her serum. Platelet count,
fibrinogen, and other routine blood chemistry tests were normal. The prolonged APTT was not corrected by mixture of the patient's plus normal plasma. Clotting activities of factors II, V, VIII, IX, X, XI, and XII reduced. Further examinations revealed the presence of
lupus anticoagulant (LA),
phosphatidylserine-dependent anti-
prothrombin antibodies (aPS/PT), and
anticardiolipin antibodies.
Mycoplasma pneumonia was treated by
minocycline and the patient's skin lesions disappeared spontaneously within a week. During follow-up, she showed no other
bleeding symptoms, and no signs of SLE or other
autoimmune diseases. Four weeks after admission to our hospital, blood coagulation tests and serum complements normalized. Clotting activities of factors and
antiphospholipid antibodies were not detected, half year later. The
bleeding in this case was associated with
acquired hypoprothrombinemia caused by
antiphospholipid antibodies following acute adenovirus
gastroenteritis and
mycoplasma pneumonia.