Chronic Splenic Melioidosis in a Patient with Fever of Unknown Origin Diagnosed by Metagenomics Next-Generation Sequencing: An Emerging Cause and Literature Review

INTRODUCTION: Human melioidosis is an emerging infectious disease in tropical areas of China, and chronic melioidosis can be a rare cause of fever of unknown origin (FUO). Timely diagnosis may improve the prognosis of melioidosis. CASE PRESENTATION: We report a case of melioidosis with splenic abscesses caused by Burkholderia pseudomallei in a 57-year-old man, who presented with FUO. Positron emission tomography/computed tomography (PET/CT) revealed multiple hypermetabolic lesions in the spleen. The spleen biopsy was conducted and metagenomics next-generation sequencing (mNGS) of the spleen specimen identified the presence of B. pseudomallei, confirming the diagnosis of melioidosis. Antimicrobial treatment was initiated with intravenous meropenem, followed by oral faropenem. During the follow-up, the patient was in good condition except having a low-grade fever occasionally. A splenectomy was performed, and subsequent culture and mNGS of the spleen pus were both positive for B. pseudomallei. Histopathological characteristics of chronic splenic melioidosis were noted. CONCLUSION: Melioidosis is a serious endemic disease, and it is critical to raise awareness about this disease.