1. Faculty of Medicine, Universitas Sumatera Utara, Medan 20155, Indonesia
2. Department of Clinical Pathology, Faculty of Medicine, Universitas Sumatera Utara, Medan 20155, Indonesia
3. Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan 20155, Indonesia
4. Department of Anaesthesiology and Intensive Care, Faculty of Medicine, Universitas Sumatera Utara, Medan 20155, Indonesia