[Long COVID: long-term symptoms and morphological/radiological correlates].

Background: Neurologic, pulmonary, cardiac and gastrointestinal functional disorders can persist in the post-acute phase and constitute a long COVID syndrome, also known as post-acute sequelae of SARS-CoV‑2 infection (PASC). Some patients develop persistent and debilitating symptoms despite a relatively mild illness at onset and they are known as COVID-19 long haulers.

Objective: Presentation of symptoms, signs and biomarkers present in patients previously affected by COVID-19 and discussion of possible underlying mechanisms and consequences.

Methods: Existing literature and reported cases as well as expert opinions are analyzed and discussed.

Results: Long COVID affects survivors of COVID-19 at all levels of disease severity, even in mild to moderate cases and younger adults who did not require respiratory support, hospitalization or intensive care. A challenging aspect is that many long haulers never had laboratory confirmation of COVID-19, raising skepticism that the persistent symptoms have a physiological basis. On the other hand, some symptoms seen in post-acute COVID-19 may occur as a consequence of critical illness or as a side effect of treatment.

Conclusion: Given that COVID-19 is a new disease, it is not possible to determine how long these effects will last. Long-term monitoring of post-acute COVID-19 symptoms and screening for frequent comorbid conditions are essential.