Acute and Chronic Q Fever in a Child With Repaired Tetralogy of Fallot: A Case Report.

In children, Q fever often presents as an acute febrile illness, sometimes with pneumonia or hepatitis. We report in this case a 38-month-old girl with complex congenital heart disease (tetralogy of Fallot, pulmonary atresia, and ventricular septal defect) who presented with a four-day history of fever, shortness of breath, and vomiting. She had prior cardiac interventions. After admission to the PICU, she was initially treated for severe pneumonia. During her stay, her condition worsened with heart failure, hepatosplenomegaly, and pancytopenia. After extensive investigations, Q fever serology was positive, indicating chronic Q fever. The patient was treated with doxycycline and hydroxychloroquine for 18 months. Her liver function improved, and echocardiography was normal after four months. This case highlights the importance of considering Q fever in pediatric patients with cardiac history, the need for comprehensive investigations, and appropriate long-term antibiotic treatment.