An elder female patient without a significant medical history underwent a chest computed tomography (CT) for the evaluation of chronic cough and shortness of breath after recovering from COVID-19 pneumonia 5 months ago. Noncontrast chest CT images demonstrated bilateral, peripherally located, parenchymal abnormalities consistent with healing organizing pneumonia. The parenchymal findings were in keeping with a history of prior COVID-19 pneumonia. No mediastinal or right axillary lymphadenopathy was identified. However, mildly enlarged left axillary and subpectoral lymph nodes were noted [Figure 1]. A contrast-enhanced chest CT which was obtained 6 months ago was available [Figure 2]. The comparison of the two studies revealed interval enlargement of the left axillary lymph nodes. The largest lymph node was measured 13 mm in the short axis on the recent study, while it was 7 mm on the prior examination. In addition, the patient had a screening bilateral mammography (not shown) 2 weeks ago, which also demonstrated normal-sized (maximum 7 mm) left axillary lymph nodes. Further history revealed that the patient had Pfizer-BioNTech mRNA COVID-19 vaccination 3 days before the CT examination. Unilateral lymphadenopathy secondary to vaccination is well-known entity after BCG or smallpox vaccinations. Recently, it has also been reported in patients after the administration of new mRNA COVID-19 vaccinations. It is important to keep in mind that unilateral lymphadenopathy can be related to recent COVID 19 vaccination in the pandemic era to avoid misdiagnosis, especially in patient who undergone breast screening, and to avoid further unnecessary interventions.
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1. Cohen J, Powderly WG, Opal SM. Infectious diseases Elsevier Health Sci. 2017;2:145
2. Mehta N, Sales RM, Babagbemi K, Levy AD, McGrath AL, Drotman M, et al Unilateral axillary lymphadenopathy in the setting of COVID-19 vaccine Clin Imaging. 2021;75:12–15
3. Ahn RW, Mootz AR, Brewington CC, Abbara S. Axillary Lymphadenopathy After mRNA COVID-19 Vaccination Radiol Cardiothorac Imaging. 2021;3:e210008