[Challenges concerning lymphadenopathy after COVID-19 vaccination]

Reactive lymphadenopathy after COVID-19 vaccination occurs frequently and usually recovers within 1-2 weeks. It can, however, persist for more than six months in some cases. Axillary lymphadenopathy at the site of vaccination is most common. Cervical and supraclavicular lymphadenopathy is also reported. A wait-and-see approach for 2-3 weeks seems justified when time between onset of lymphadenopathy and covid-19 vaccination is several days to weeks, there is no progression, lymphadenopathy is unilateral and localised axillary or cervical in patients without a history of malignancy and without alarm symptoms. In cases of persistent lymphadenopathy, ultrasound of the affected lymph node is recommended. In cases of unilateral axillary lymphadenopathy in women, breast examination with mammography and/or breast ultrasound is also warranted. In the absence of any abnormalities referral to secondary care can be delayed for 8-12 weeks. After this time period we advise referral to secondary care to exclude any underlying illness.