Immunocompromised Patients with Protracted COVID-19: a Review of "Long Persisters"

Certain immunocompromised individuals are at risk for protracted COVID-19, in which SARS-CoV-2 leads to a chronic viral infection. However, the pathogenesis, diagnosis, and management of this phenomenon remain ill-defined.

Herein, we review key aspects of protracted SARS-CoV-2 infection in immunocompromised individuals, or the so-called long persisters, and describe the clinical presentation, risk factors, diagnosis, and treatment modalities of this condition, as well as intra-host viral evolution. Based on the available data, we also propose a framework of criteria with which to approach this syndrome.

Protracted COVID-19 is an uncharacterized syndrome affecting patients with B-cell depletion; our proposed diagnostic approach and definitions will inform much needed future research.