Serum ferritin as an independent risk factor for severity in COVID-19 patients.
Serum ferritin is an iron storage protein that is widely measured as an indicator of iron status, but it is also a well-known inflammatory marker.
The mechanisms responsible for the association of hyperferritinemia and disease severity in patients with COVID-19 are :
- Proinflammatory cytokines such as interleukin-Iβ (IL-lβ), tumor necrosis factor-a (TNF-α), and IL-6 may increase ferritin synthesis.
- The cellular damage derived from inflammation can promote the leakage of intracellular ferritin, thus elevating serum ferritin.
- In acidosis, the microvascular environment and increased production of reactive oxygen species (ROS) might liberate iron from ferritin, and it is this unliganded iron that can participate in Haber-Weiss and Fenton reactions, creating hydroxyl radicals,causing further cellular damage,and worsening tissue injury, thus causing a vicious cycle of inflammation.