Lymphadenopathy after the Anti-COVID-19 Vaccine: Multiparametric Ultrasound Findings

• Main Authors: Giulio Cocco, Andrea Delli Pizzi, Stefano Fabiani, Nino Cocco, Andrea Boccatonda, Alessio Frisone, Antonio Scarano, Cosima Schiavone
• Format: Article
• Language: English
• Published: MDPI AG 2021-07-01
• Series: Biology
• Subjects: lymphadenopathy; anti-COVID-19 vaccines; ultrasound
• Online Access: https://www.mdpi.com/2079-7737/10/7/652

<i>Background</i>: Post-anti-COVID-19 vaccine lymphadenopathy has recently been described in the literature. In this study, we investigated the multiparametric US findings of patients with post-vaccine lymphadenopathy and compared these findings among different anti-COVID-19 vaccines. <i>Methods</i>: We retrospectively evaluated 24 patients who underwent US between January and May 2021 due to post-anti-COVID-19 lymphadenopathy. The presence, size, location, number, morphology, cortex-hilum, superb microvascular imaging (SMI) and elastosonography of lymph nodes were assessed. Descriptive statistics were calculated and differences among anti-COVID-19 vaccines were analyzed using the Kruskal–Wallis test. A <i>p</i>-value ≤ 0.05 was considered statistically significant. <i>Results</i>: Sixty-six nodes were assessed. They were axillary (mean 1.6 cm ± 0.16) in 11 patients (45.8%) and supraclavicular (mean 0.9 cm ± 0.19) in 13 patients (54.2%). In 20 patients (83.3%), the number of nodes was ≤3. Prevalent US features included oval morphology (18, 75%), asymmetric cortex with hilum evidence (9, 37.5%), central and peripheral vascular signals (12, 50%) at SMI and elastosonography patterns similar to the surrounding tissue (15, 71.4%). No significant differences among the three anti-COVID-19 vaccines were observed (<i>p</i> > 0.05). <i>Conclusions</i>: Anti-COVID-19 vaccines may present lymphadenopathy with “worrisome” US features regarding size, shape, morphology, cortex-hilum, SMI and elastosonography. An awareness of the patient’s history and US findings may help in the early recognition of this clinical scenario and in the appropriate selection of patients for a short-term US follow-up.