Prognosis and follow-up of patients with prosthetic valve endocarditis treated conservatively in relation to WBC-SPECT imaging.

BACKGROUND: Our objective was to evaluate in patients with prosthetic valve endocarditis (PVE) treated conservatively, the prognostic value of white blood cell (WBC) signal intensity on SPECT and to describe the evolution of the WBC signal under antibiotics. METHODS: Patients with PVE treated conservatively and positive WBC-SPECT imaging were identified retrospectively. Signal intensity was classified as intense if equal to or higher, or mild if lower, than the liver signal. Clinical, biological, imaging and follow-up information were collected from medical files. RESULTS: Among 47 patients, WBC signal was classified as intense in 10 patients and as mild, in 37. The incidence of the primary composite endpoint (death, late cardiac surgery, or relapse) was significantly higher in patients with intense vs. mild signal (90% vs. 11%). Twenty-five patients underwent a second WBC-SPECT imaging during follow-up. The prevalence of WBC signal decreased progressively from 89% between 3 and 6 weeks to 42% between 6 and 9 weeks and 8% more than 9 weeks after initiation of antibiotics. CONCLUSIONS: In patients with PVE treated conservatively, intense WBC signal was associated with poor outcome. WBC-SPECT imaging appears as an interesting tool for risk stratification and to monitor locally the efficacy of antibiotic treatment.

Total Metabolic Tumor Volume on 18F-FDG PET/CT Is a Useful Prognostic Biomarker for Patients with Extensive Small-Cell Lung Cancer Undergoing First-Line Chemo-Immunotherapy.

Background: We aimed to evaluate the prognostic value of imaging biomarkers on 18F-FDG PET/CT in extensive-stage small-cell lung cancer (ES-SCLC) patients undergoing first-line chemo-immunotherapy. Methods: In this multicenter and retrospective study, we considered two cohorts, depending on the type of first-line therapy: chemo-immunotherapy (CIT) versus chemotherapy alone (CT). All patients underwent baseline 18-FDG PET/CT before therapy between June 2016 and September 2021. We evaluated clinical, biological, and PET parameters, and used cutoffs from previously published studies or predictiveness curves to assess the association with progression-free survival (PFS) or overall survival (OS) with Cox prediction models. Results: Sixty-eight patients were included (CIT: CT) (36: 32 patients). The median PFS was 5.9:6.5 months, while the median OS was 12.1:9.8 months. dNLR (the derived neutrophils/(leucocytes-neutrophils) ratio) was an independent predictor of short PFS and OS in the two cohorts (p < 0.05). High total metabolic tumor volume (TMTVhigh if > 241 cm3) correlated with outcomes, but only in the CIT cohort (PFS for TMTVhigh in multivariable analysis: HR 2.5; 95%CI 1.1-5.9). Conclusion: Baseline 18F-FDG PET/CT using TMTV could help to predict worse outcomes for ES-SCLC patients undergoing first-line CIT. This suggests that baseline TMTV may be used to identify patients that are unlikely to benefit from CIT.

Aortitis PET Imaging in VEXAS Syndrome: A Case Report.

ABSTRACT: VEXAS (vacuoles, E1 enzyme, X-LINKED, autoinflammatory, somatic) syndrome is a complex inflammatory disease associated with somatic mutations of the ubiquitin-like modifier activating enzyme 1 (UBA1) gene. A 75-year-old man with a medical history of thrombophlebitis, leukocytoclastic vasculitis, chronic inflammatory arthralgia, elevated inflammatory markers, and anemia was diagnosed with VEXAS syndrome. 18F-FDG PET/CT showed thoracic aortitis, a rare involvement during VEXAS syndrome. Corticosteroid therapy monitored with 18F-FDG PET/CT led to a complete metabolic response.

Diagnostic performance of White Blood Cell SPECT imaging against intra-operative findings in patients with a suspicion of prosthetic valve endocarditis.

AIM: The objective of this study was to evaluate the diagnostic performance of white blood cells (WBC)-SPECT imaging in patients with suspicion of prosthetic valve endocarditis (PVE) against intra-operative findings. METHODS: 36 consecutive patients who underwent cardiac surgery 30 days after WBC-SPECT imaging were identified retrospectively. Clinical, imaging, and biological results were collected from reports. WBC-SPECT results were classified as positive or negative and, if positive, the intensity of signal graded as intense or mild. Lesions observed during cardiac surgery were collected from surgeons' reports. RESULTS: The 20 patients with positive WBC-SPECT study had confirmed PVE intra-operatively. Patients with intense signal on WBC-SPECT had high prevalence of abscesses (83%) compared to patients with only mild signal (12%). The three patients with negative WBC-SPECT but confirmed PVE had longer duration of antibiotic treatment before imaging and had no perivalvular abscess. Sensitivity, specificity, positive predictive and negative values, and accuracy of WBC-SPECT were measured at 87%, 100%, 100%, 81%, and 92%, respectively. Addition of WBC-SPECT results to the modified Duke score helped re-classify correctly 25% of patients from possible to definite PVE. CONCLUSION: In patients with suspicion of PVE, WBC-SPECT imaging provides excellent diagnostic performance against intra-operative findings.