Administration of some COVID-19 vaccines can cause an exacerbation of the systemic capillary leak syndrome (ACLS).

Patient selection: acute systemic capillary leak syndrome (ACLS)


Implicated vaccines: use of adenovirus vector or mRNA


Clinical features:

(1) The patient has a history of ACLS, currently quiescent.

(2) Shortly after receiving a COVID-19 vaccination the patient suffers an exacerbation of the ACLS (with hypotension, anasarca, hypoalbuminemia and hemoconcentration).

(3) There is no better explanation for the exacerbation.

(4) Resolution after prompt therapy (steroids and/or high-dose intravenous immunoglobulins)


The reaction may be prevented by pre-vaccination infusion of IVIg, but the choice of another vaccine may be appropriate.

To read more or access our algorithms and calculators, please log in or register.