Threshold protective levels of serum IgG to Shigella lipopolysaccharide: re-analysis of Shigella vaccine trials data.

OBJECTIVES: Establishing a correlate of protection is essential for the development and licensure of Shigella vaccines. We examined potential threshold levels of serum IgG to Shigella lipopolysaccharide (LPS) that could predict protection against shigellosis. METHODS: We performed new analyses of serologic and vaccine efficacy (VE) data from two randomized vaccine-controlled trials of the Shigella sonnei-Pseudomonas aeruginosa recombinant exoprotein A (rEPA) conjugate conducted in young adults and children aged 1-4 years in Israel. Adults received either S. sonnei-rEPA (n = 183) or control vaccines (n = 277). Children received the S. sonnei-rEPA conjugate (n = 1384) or S. flexneri 2a-rEPA conjugate (n = 1315). VE against culture-proven shigellosis was determined. Sera were tested for IgG anti-S. sonnei LPS antibodies. We assessed the association of various levels of IgG anti-S. sonnei LPS antibodies with S. sonnei shigellosis risk using logistic regression models and the reverse cumulative distribution of IgG levels. RESULTS: Among adults, four vaccinees and 23 controls developed S. sonnei shigellosis; the VE was 74% (95% CI, 28-100%). A threshold of ≥1:1600 IgG anti-S. sonnei LPS titre was associated with a reduced risk of S. sonnei shigellosis and a predicted VE of 73.6% (95% CI, 65-80%). The IgG anti-S. sonnei LPS correlated with serum bactericidal titres. In children, a population-based level of 4.5 ELISA Units (EU) corresponding to 1:1072 titre, predicted VE of 63%, versus 71% observed VE in children aged 3-4 years. The predicted VE in children aged 2-4 years was 49%, consistent with the 52% observed VE. CONCLUSION: Serum IgG anti-S. sonnei LPS threshold levels can predict the degree of VE and can be used for the evaluation of new vaccine candidates.

A Prospective Evaluation of Quality of Life in Patients Undergoing Extended Endoscopic Endonasal Surgery for Benign Pituitary Gland Lesion.

Introduction Endoscopic endonasal surgery (EES) has become the preferred approach for pituitary tumor resection. Nevertheless, research on quality of life related to pituitary adenoma surgery is scarce. Objective The aim of the study is to evaluate short-term quality of life in patients after endoscopic endonasal resection of pituitary tumors and to find predictors for poor quality of life (QOL) outcome. Materials and Methods A prospective cohort study was conducted, including all patients who underwent EES for pituitary tumors in a tertiary medical referral center. Recruited patients completed the Anterior Skull Base Disease-Specific QOL (ASBS-Q) questionnaire and the Sinonasal Outcome Test 22 (SNOT-22) questionnaire before surgery, 2 and 4 to 6 months after surgery. Demographic and clinical data was collected. Results Our study included 49 patients. The overall ASBS-Q scores significantly improved 4 to 6 months after surgery (4.46 vs. 4.2, p < 0.05). We found a significant improvement in QOL related to emotional state 2 months post surgery (4.41 vs. 3.87, p < 0.05), which became borderline significant 4 to 6 months post surgery. There was a significant improvement in pain (4.5 vs. 4.08, p < 0.05) and vitality (4.43 vs. 4.16, p < 0.05) domains 4 to 6 months post surgery. SNOT-22 scores did not change significantly postoperatively. Factors such as secreting and non-secreting tumors, tumor size, intraoperative cerebrospinal fluid leak, gross tumor resection, endocrine remission, and the use of nasoseptal flap reconstruction did not have a significant effect on QOL. Conclusion We found that patients after EES reported improved QOL 4 to 6 months post surgery. Specific improvement was noted in the QOL related to pain and vitality.

Metal Artifact Reduction in Routine Chest and Abdominal Examinations Using Virtual Monoenergetic Images From Spectral Detector Computed Tomography.

OBJECTIVE: The objective of this study was to investigate the quantitative and qualitative effects of virtual monoenergetic images (VMIs) by spectral detector computed tomography (SDCT) on metal artifacts in routine examinations. METHODS: Fifty-nine patients with metal artifacts (caused by pacemakers, ports, screws, or prosthetic joints) affecting muscular tissue in the chest and/or abdomen were scanned using SDCT. Attenuation values around the metallic device were compared with contralateral unaffected values, for conventional images and 80 to 200 keV VMIs. In addition, general image quality and artifact intensity were rated by 2 readers. RESULTS: The VMIs significantly decreased metal artifact intensity in all patients (P < 0.05). In 39 patients (66.1%), the attenuation values of the artifact and the unaffected area on the optimal keV level were very similar (≤5 Hounsfield unit difference). Qualitative analysis showed that high VMIs significantly improved artifact intensity, with best scores at 140 keV. CONCLUSIONS: High monoenergetic images of SDCT significantly reduce metal artifacts, with optimal assessment at 140 keV.