TABLE 1.

Summary table of most frequent hematological biomarkers of Long COVID.

Hematological parameter	Status in long COVID
Cells and cellular parameters
RBC	↓(Kubánková et al., 2021; Grau et al., 2022; Lin et al., 2022)
MCV	↑(Lin et al., 2022)
MCHC	↑(Alfadda et al., 2022)
Lymphocytes	↓ (Mandal et al., 2021; Moreno-Pérez et al., 2021; Alfadda et al., 2022); ↔(Darcis et al., 2021)
Blood components and proteins
Hemoglobin	↓(Kubánková et al., 2021; Pasini et al., 2021; Grau et al., 2022; Pereira-Roche et al., 2022); ↔ (Darcis et al., 2021; Alfadda et al., 2022)
Platelet count	↔ (Mandal et al., 2021; Pasini et al., 2021; Alfadda et al., 2022)
D-dimer	↑ (Mandal et al., 2021; Moreno-Pérez et al., 2021; Pasini et al., 2021; Fan et al., 2022; Kalaivani and Dinakar, 2022)
Ferritin	↑ (Moreno-Pérez et al., 2021; Pasini et al., 2021); ↔(Darcis et al., 2021; Mandal et al., 2021; Alfadda et al., 2022; Pérez-González et al., 2022)
C-reactive protein (C.R.P.)	↑ (Mandal et al., 2021; Pasini et al., 2021; Pérez-González et al., 2022); ↔ (Darcis et al., 2021; Kalaivani and Dinakar, 2022)
Lactate dehydrogenase	↔(Moreno-Pérez et al., 2021; Pasini et al., 2021; Alfadda et al., 2022)
Cytokines
IL-6	↑ (Fan et al., 2022; Schultheiß et al., 2022); ↓(Williams et al., 2022); ↔ (Kalaivani and Dinakar, 2022; Queiroz et al., 2022)
TNF-α	↑(Peluso et al., 2021; Schultheiß et al., 2022); ↔ (Queiroz et al., 2022; Williams et al., 2022)
IL-1β	↑(Schultheiß et al., 2022); ↔ (Williams et al., 2022)
IL-2	↓ (Williams et al., 2022); ↑ (Queiroz et al., 2022)
IL17	↓ (Williams et al., 2022); ↑(Queiroz et al., 2022)
IFNγ	↓(Williams et al., 2022); ↔ (Queiroz et al., 2022)
IFN-β	↑(Phetsouphanh et al., 2022)
IFN-λ1	↑(Phetsouphanh et al., 2022)
IL-8	↓(Williams et al., 2022); ↔ (Schultheiß et al., 2022); ↑(Phetsouphanh et al., 2022)
IL-10	↔ (Williams et al., 2022); ↓(Queiroz et al., 2022)
IL-4	↓(Queiroz et al., 2022; Williams et al., 2022); ↔(Schultheiß et al., 2022)

Note: ↔ denotes no significant change to a reference value or control group, while ↑ denotes an increase and ↓ denotes a decrease in the parameter.