Incomplete Kawasaki disease associated with acute icteric hepatitis and Torque teno virus infection: a case report and literature review

INTRODUCTION: Kawasaki disease (KD) is an acute, self-limiting vasculitis that primarily affects children under five years of age. Its classic clinical features include prolonged fever, bilateral conjunctival injection, changes in the lips and oral cavity, cervical lymphadenopathy, rash, and extremity changes. Acute jaundice and liver dysfunction are atypical manifestations of KD. Cases in which jaundice is the initial presenting symptom-especially when accompanied by Torque Teno Virus (TTV) infection-are rarely reported. CASE PRESENTATION: We describe a 17-month-old boy diagnosed with incomplete Kawasaki disease (IKD), who initially presented with persistent fever, jaundice, and elevated liver enzymes. At disease onset, characteristic mucocutaneous signs of KD were absent. As the illness progressed, the patient developed dorsal foot edema, erythematous lips, and cervical lymphadenopathy. On the ninth day of illness, echocardiography revealed dilation of the left coronary artery, confirming a retrospective diagnosis of IKD. Additionally, high-throughput sequencing of peripheral blood identified TTV type 28. The patient was treated with intravenous immunoglobulin, methylprednisolone, and hepatoprotective agents. Following treatment, his fever resolved, jaundice subsided, liver function normalized, and coronary artery dimensions gradually returned to within the normal range. CONCLUSIONS: This case highlights an atypical presentation of IKD, characterized by early-onset jaundice and later development of coronary artery dilation, in a patient also infected with TTV. To our knowledge, this is the first reported case of IKD associated with acute icteric hepatitis and TTV infection. This case may inform clinical evaluation in similar presentations and contribute to future research on the etiology of KD.