Background: Despite advancements in medical examination equipment and techniques, fever of unknown origin (FUO) remains challenging in internal medicine.Purpose: This study evaluates the diagnostic efficacy and necessity of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in patients with FUO.Methods: We retrospectively analyzed the results of 18F-FDG PET/CT in a cohort of 284 patients with FUO admitted to the Department of Infection at the First Hospital of Jilin University between January 2018 and March 2024. All patients received a final clinical diagnosis after various treatments, which helped determine the diagnostic relevance of identified lesions using 18F-FDG PET/CT. Additionally, univariate and multivariate logistic regression analyses were performed to evaluate the predictive value of relevant laboratory indices on the true-positive results of 18F-FDG PET/CT. The diagnostic performance for different etiologies of FUO was assessed by calculating the area under the receiver operating characteristic curve.Results: Of the 284 enrolled patients, infectious diseases were diagnosed in 53 (18.7%), non-infectious inflammatory diseases in 76 (26.8%), malignant tumors in 66 (23.2%), and 89 (31.3%) remained undiagnosed. The final diagnoses of 136 patients (47.9%) correlated with their 18F-FDG PET/CT results, yielding a sensitivity of 79.5%, specificity of 61.1%, positive predictive value of 75.6%, and negative predictive value of 66.3%. Furthermore, a correlation was found between localized pain, prolonged activated partial thromboplastin time, and true-positive 18F-FDG PET/CT results.Conclusion: The high diagnostic efficacy of 18F-FDG PET/CT in FUO suggests its potential as a routine imaging modality, which could enhance patient management and reduce the need for costly and unnecessary invasive procedures. The identification of clinical factors that are predictive of true-positive diagnosis could facilitate more effective allocation of PET/CT imaging.

Background: When individuals infected with human immunodeficiency virus (HIV) experience pulmonary infections, they often exhibit severe symptoms and face a grim prognosis. Consequently, early, rapid, and accurate pathogen diagnosis is vital for informing effective treatment strategies. This study aimed to use metagenomic next-generation sequencing (mNGS) and targeted mNGS (tNGS) to elucidate the characteristics of pulmonary infections in HIV and non-HIV individuals.Methods: This study enrolled 90 patients with pulmonary infection at the Department of Infectious Diseases of The First Hospital of Jilin University from June 2022 to May 2023, and they were divided into HIV (n=46) and non-HIV (n=44) infection groups. Their bronchoalveolar lavage fluid (BALF) was collected for mNGS analysis to evaluate the differences in pulmonary infection pathogens, and tNGS detection was performed on BALF samples from 15 HIV-infected patients.Results: A total of 37 pathogens were identified in this study, including 21 bacteria, 5 fungi, 5 viruses, 5 mycobacteria, and 1 mycoplasma. The sensitivity of mNGS was 78.9% (71/90), which is significantly higher than that of conventional methods (CTM) (39/90, P=1.5E-8). The combination of mNGS with CTM can greatly enhance the sensitivity of pathogen detection. The prevalence of Pneumocystis jirovecii (82.6% vs. 9.1%), cytomegalovirus (CMV) (58.7% vs. 0%), and Epstein-Barr virus (EBV) (17.4% vs. 2.3%) was significantly higher in the HIV infection group than in the non-HIV infection group (P<0.05). Although no statistically significant difference was observed, the detection rate of Mycobacteria was higher in HIV-infected patients (17.4%) than in the non-HIV group (6.8%). Furthermore, the tNGS results of BALF from 15 HIV-infected patients were not entirely consistent with the mNGS results., and the concordance rate of tNGS for the detection of main pathogens reached 86.7% (13/15).Conclusion: Next-generation sequencing (NGS) can accurately detect pathogens in the BALF of patients with pulmonary infection. The sensitivity of tNGS is comparable to that of mNGS. Therefore, this technique should be promoted in the clinic for better patient outcomes.

Background: With the increasing popularity of ARVs, physical symptoms of people living with HIV/AIDS (PLWHA) have been effectively improved. Improving mental health and quality of life has gradually become the focus of attention in the treatment. The aim of this study is to explore the association between death anxiety and depression in men living with HIV/AIDS (MLWHA) from the perspective of network analysis. Methods: This study recruited 701 MLWHA in Jilin Province, China. Participants were asked to complete a questionnaire. The average age of the participants was 37.4 years old. Among them, there were 54 heterosexual participants, 494 homosexual participants, 139 bisexual participants, and 14 asexual/other participants. Network analysis was used to identify central symptoms, key bridge symptoms, and the strongest edge among symptoms in the death anxiety and depression network. Results: In this study, 18.1% of MLWHA may suffer from severe depression. The severity of depression in homosexual MLWHA was severer than in heterosexuals. Death anxiety was severer among unmarried and married/cohabiting MLWHA compared to divorced/separated/widowed MLWHA. This study found that item DAS10 (The topic of post death is very confusing to me) was the most central symptom. The edge DAS2 – PHQ9 (Rarely think of death – Suicide ideation) was the strongest edge between death anxiety and depression. Item DAS2 (Rarely think of death) was the strongest bridge symptom. Conclusion: Psychological symptoms such as distress over the topic of death, thoughts of death, and suicidal ideation play an important influential and connecting role in the death anxiety-depression network among MLWHA. Implementing appropriate interventions for these symptoms—such as popularizing correct knowledge of death and providing more psychological counseling services for this group—can effectively reduce the co-occurrence of death anxiety and depression, thereby improving the mental health of MLWHA.

Background: The host’s immune status is a critical determinant of the pathogen profile in pulmonary infections, but quantitative indicators to delineate this dynamic association are lacking. This study aimed to use CD4 ⁺ T cells count as an objective parameter to systematically characterize the evolution of the pathogen profile in bronchoalveolar lavage fluid-targeted next-generation sequencing (BALF-tNGS) from patients with severe pneumonia. Methods: We retrospectively analyzed 286 adult patients who underwent BALF-tNGS for severe pneumonia. Patients were stratified into four strata based on CD4 ⁺ T cells count: severe immunosuppression, moderate immunosuppression, low-normal immunity, and immunocompetent. Cochran-Armitage trend test, cluster analysis, and Kruskal-Wallis test were used to analyze the associations between CD4 ⁺ T cells strata and pathogen detection rates/co-infection complexity. Results: The detection rates of Pneumocystis jirovecii ( PJP ) and Cytomegalovirus (CMV) showed a highly significant increasing trend with decreasing CD4 ⁺ T cells strata ( p < 0.05). CD4 ⁺ T cells count < 100 cells/μL was the most significant risk factor for PJP infection (detection rate 39.6%). Meanwhile, as the CD4 ⁺ T cells count decreased, the number of pathogen species detected in the patient’s BALF significantly increased, with a statistically significant difference between groups ( p < 0.05). The median number in the severe immunosuppression stratum was significantly higher than that in the immunocompetent stratum. Conclusion: The CD4 ⁺ T cells count quantitatively defines the pathogen ecology in pulmonary infections. A CD4 ⁺ T cells count < 100 cells/μL represents a critical threshold for opportunistic infections and complex co-infections. These findings support the integration of CD4 ⁺ T cells counting into the initial assessment framework for severe pneumonia to guide precise empirical therapy and diagnostic strategies.

HIV-1 persists as a global health burden due to latent reservoirs and immune evasion that undermine eradication efforts, even under antiretroviral therapy (ART). To address this challenge, we developed a novel FITC.CAR strategy, incorporating an anti-FITC single-chain variable fragment (scFv), to selectively target HIV-1-infected cells when conjugated with FITC-labeled broadly neutralizing antibodies (bNAbs). FITC.CAR-T cells achieved up to ~70 % cytotoxicity against HIV-1-infected CD4⁺ T cells across subtypes B, C, and O, and demonstrated markedly enhanced clearance of reactivated latent HIV-1 reservoirs in both viral latent cell lines and CD4⁺ T cells derived from HIV-infected patient with ART compared to controls. In a humanized BLT mouse model, this strategy led to an approximate 90 % reduction in HIV-1 loads after ART interruption. By coupling the specificity of bNAbs with the cytolytic power of CAR-T cells, this strategy offers a flexible and effective platform for achieving a functional HIV-1 cure.