Abstract
We report a middle-childhood girl presented with high-grade fever and headache for 4 days. Following this, the child developed mucocutaneous symptoms. She had a notable family history of autoimmune disease. Tests revealed increased inflammatory markers. On the sixth day of illness, a two-dimensonal echocardiogram showed an enlarged coronary artery, diagnosed as incomplete Kawasaki disease (KD) and treated with IVIG and aspirin.Within a week, her younger sibling, an early-childhood girl presented with features of viral prodrome, developed mucocutaneous lesions and subcutaneous oedema of limbs. Her investigations also showed elevated inflammatory markers and echocardiographic changes, diagnosed as incomplete KD.The subsequent development of KD in siblings, both showing initial viral symptoms and a family history of autoimmune disease, led to the suspicion of a potential viral trigger. This was confirmed through viral PCR studies for human adenovirus (type 3). These cases highlight an unusual occurrence of KD developing in siblings following acute adenoviral infection.