18F-FDG PET/CT Imaging of Talaromyces marneffei Infection with Bone Destruction in an HIV-Negative Patient: Case Report and Review

Wenting He,1 Senhui Wang,1 Xiaoqi Xiong,2 Wenli Dai1 1Department of Nuclear Medicine, The First College of Clinical Medical Science, China Three Gorges University, Yichang, Hubei, 443003, People’s Republic of China; 2Department of Respiratory and Critical Care Medicine, The First College of Clinical Medical Science, China Three Gorges University, Yichang, Hubei, 443003, People’s Republic of ChinaCorrespondence: Wenli Dai, Department of Nuclear Medicine, The First College of Clinical Medical Science, China Three Gorges University, Yichang, Hubei, 443003, People’s Republic of China, Email [email protected]: Talaromycosis is an opportunistic fungal infection caused by Talaromyces marneffei (T. marneffei), commonly occurs in HIV-positive individuals. While less common, it can also affect HIV-negative individuals. We reported a T. marneffei infection in an HIV-negative patient, whose imaging findings and diagnostic process offer valuable clinical insights.Case Presentation: An HIV-negative male adult patient with an intermittent cough for more than two years and worsened for more than one month. Enhanced CT scan indicated lung cancer with rib and lymph nodes metastasis. The lower respiratory tract and bronchial lavage fluid culture of the patient were negative. He received two bronchoscopies, two biopsies and two metagenomic next-generation sequencing (mNGS) tests, which failed to find the malignant cell but sequentially identified the presence of Pasteurella multocida and the Epstein-Barr virus. His condition did not improve after anti-infective treatment for 2weeks. An 18-fluorodeoxy glucose (18F-FDG) PET/CT scan revealed increased radioactivity in right supraclavicular lymph node, left lung and the right tenth rib. Ultimately, a biopsy at the hypermetabolic lesion of left lung, and a third mNGS test confirmed the presence of Talaromyces marneffei. Subsequently, the patient started antifungal therapy with amphotericin B and itraconazole and showed a favorable response.Conclusion: We reviewed all reported PET/CT findings of T. marneffei infection patients, suggesting that fungus T. marneffei should be considered in patients identified as infection and exhibited bone destruction and also highlight the role of PET/CT in guiding the biopsy site.Keywords: Talaromyces marneffei, PET/CT, HIV-negative, bone destruction, metagenomic next-generation sequencing (mNGS)