A 21-year-old man presented with 6 weeks of unexplained fever, pharyngitis, enlarged cervical neck lymph nodes, night sweats and severe fatigue. The patient was treated as an outpatient with antibiotics for acute tonsillitis twice without any improvement. He had persistent daily fever and a 6 kg unintentional weight loss. No significant past medical history. Epstein-Barr virus (EBV) and Cytomegalovirus (CMV) titers drawn one week after debut of symptoms were negative. Three months before presenting with symptoms the patient had been travelling in South East Asia for 3.5 months. He had not been sick during his travel abroad. Physical examination was significant for lymphadenopathy at the cervical neck. No splenomegaly was noted. At admission white blood cells was 13.0 × 109/L (normal range: 3.5–8.8 × 109/L) with 10.0 × 109/L lymphocytes (normal range: 1.0–3.5 × 109/L). Alanine aminotransferase (ALT) was elevated at 104 U/L (normal range: 10–70 U/L) and Lactate dehydrogenase (LDH) was elevated at 939 U/L (normal range: 105–205 U/L). Due to concern of malignant lymphoma an 18F-FDG PET/CT was performed (Figure 1). The scan revealed pathologically 18F-FDG uptake in enlarged lymph nodes in the bilateral regions of neck, axillas, lung hili, and in an enlarged spleen (18 cm). Findings were suspicious for malignant lymphoma. A lymph node biopsy was considered.