Fig. 3

A 74-year-old male presented with a fever (Tmax 38.6℃) lasting for 10 days. No significant tuberculous foci were identified on ¹⁸F-FDG PET/CT imaging. One month later, the patient revisited the clinic due to persistent fever, and echocardiography revealed newly developed pericardial effusion. A pericardial effusion puncture was performed. The analysis of the pericardial fluid demonstrated elevated levels of ADA, LDH, protein, and CA125, while serum tests showed increased ESR and CRP. Following empirical anti-tuberculosis therapy, the pericardial effusion resolved completely. Images A-B show no ¹⁸F-FDG uptake in the pericardium; Images C-D demonstrate mediastinal lymph nodes of uncertain nature with mild ¹⁸F-FDG uptake and bilateral pleural effusion. All lesions are indicated by red arrows