Kawasaki disease triggered by parvovirus infection: an atypical case report of two siblings.

There are reports of the familial occurrence of Kawasaki disease but only a few reports described Kawasaki disease in siblings. However, the familial cases were not simultaneous. In these patients the idea of infective agents as trigger must be considered.We describe two siblings with atypical presentations of Kawasaki disease; the sister was first diagnosed as having parvovirus infection with anemia and the brother was diagnosed as having myocarditis. The first patient was a 9-month-old Caucasian girl with fever, conjunctivitis, rash, and pharyngitis, and later she had cervical adenopathy, diarrhea and vomiting, leukocytosis, and anemia, which were explained by positive immunoglobulin M against parvovirus. However, coronary artery lesions with aneurysms were documented at day 26 after fever onset. An infusion of intravenous immunoglobulin and high doses of steroids were not efficacious to resolve the coronary lesions. She was treated with anakinra, despite a laboratory test not showing inflammation, with prompt and progressive improvement of coronary lesions. Her 7-year-old Caucasian brother presented vomiting and fever at the same time as she was unwell, which spontaneously resolved after 4 days. Four days later, he again presented with fever with abdominal pain, associated with tachypnea, stasis at the pulmonary bases, tachycardia, gallop rhythm, hypotension, secondary anuria, and hepatomegaly. An echocardiogram revealed a severe hypokinesia, with a severe reduction of the ejection fraction (20%). He had an increase of immunoglobulin M anti-parvovirus, tested for the index case of his sister, confirming the suspicion of viral myocarditis. He received dopamine, dobutamine, furosemide plus steroids, with a progressive increase of the ejection fraction to 50%. However, evaluating his sister's history, the brother showed a myocardial dysfunction secondary to Kawasaki shock syndrome.We report on familial Kawasaki disease in two siblings which had the same infectious trigger (a documented parvovirus infection). The brother was diagnosed as having post-viral myocarditis. However, in view of the two different and simultaneous evolutions, the girl showed Kawasaki disease with late coronary artery lesions and aneurysms, whereas the brother showed Kawasaki shock syndrome with myocardial dysfunction. We stress the effectiveness of anakinra in non-responder Kawasaki disease and the efficacy on coronary aneurysms.