COVID-19 (coronavirus disease 2019) vaccines induce immunity through different mechanisms. The aim of this study is to compare the titers of specific antibodies in subjects vaccinated with either the Pfizer-BioNTech COVID-19 vaccine or the Sinopharm vaccine. This prospective observational cohort included Jordanian adults vaccinated with two doses, 21 days apart, of either of the two aforementioned vaccines. Titers were collected 6 weeks after the administration of the second dose. Overall, 288 participants were included, of which 141 were administered the Pfizer-BioNTech vaccine, while 147 were administered the Sinopharm vaccine. Remarkably, 140 (99.3%) of the Pfizer-BioNTech vaccine recipients had positive IgG titers, while 126 (85.7%) of Sinopharm recipients had positive IgG (p < 0.001). The mean titer for IgG among Pfizer-BioNTech recipients was 515.5 ± 1143.5 BAU/mL, compared to 170.0 ± 230.0 BAU/mL among Sinopharm subjects (p < 0.001). Multivariable regression analysis showed that the Pfizer-BioNTech vaccine positively correlated with positive IgG titers (OR: 25.25; 95% CI: 3.25–196.15; p = 0.002), compared with a negative effect of cardiovascular diseases (OR: 0.33; 95% CI: 0.11–0.99; p = 0.48) on IgG titers. In conclusion, fully vaccinated recipients of the Pfizer-BioNTech vaccine had superior quantitative efficiency compared to Sinopharm recipients. A booster dose is supported for Sinopharm recipients, or those with chronic immunosuppressive diseases.

Background The role of routine lumbosacral MRI in patients presented with isolated chronic low back pain (CLBP) is still unclear. Most patients with CLBP will show diverting degenerative changes on MRI. As it is uncertain whether surgical treatment of degenerative MRI changes results in alleviation of back pain or not, the necessity of doing a diagnostic lumbosacral MRI remains questionable. This study aimed to evaluate the yield of lumbosacral MRI among Jordanian patients presented with isolated CLBP. Methods We reviewed medical records of all patients who presented to neurosurgery outpatient clinic at Jordan University Hospital from December 2016 to December 2019. Only patients with a chief complaint of isolated CLBP were included. We obtained the relevant data from the computerized medical files and detailed radiological findings from their MRI reports. Results One hundred and sixty-seven patients (167) matched the inclusion criteria. We reported positive findings in MRI in 112 patients (67%), but 55 patients (32.93%) had normal MRI findings. Dehydration of intervertebral disc was the most common finding. Positive MRI findings were most evident in the middle-age group (41–60 years old). Disc protrusion finding in middle-aged females was significantly less prevalent than males (P = 0.012). Conclusion Jordanian patients presented with CLBP have similar worldwide patterns of lumbar degenerative changes. Providing that near one-third of patients with CLBP have normal MRI findings, we suggest following a streamlined protocol for imaging of patients presented with CLBP to reduce healthcare costs.