TABLE 3.
Studies and main findings for biomarkers related to inflammation (CRP, ferritin, procalcitonin) in Covid‐19 patients
| Studied parameters | First author (year) | Region | Study period | Sample size | Categorization of hematological factors | Main findings |
|---|---|---|---|---|---|---|
| CRP | ||||||
| Guan (2020) 16 |
552 hospitals in 30 provinces, autonomous regions, and municipalities in mainland China |
11 December 2019 – 31 January 2020 | 1099 | Elevated CRP ≥10 mg/Liter | Disease severity was associated with elevated CRP; 81.5% (110/135) of severe cases vs 56.4% (371/658) of non‐severe cases presented with elevated CRP (P < .001a). The primary composite endpoint (admission to an intensive care unit, use of mechanical ventilation, or death) was also associated with elevated CRP (41/45, 91.1% vs 440/748, 58.8%, P < .001a). | |
| Wu (2020) 20 |
Jinyintan Hospital, Wuhan, China |
25 December 2019, to 13 February 2020 | 201 | hs‐CRP >5 vs ≤5 mg/L in a bivariate Cox regression model | Higher hs‐CRP was associated with ARDS development (HR = 4.81, 95%CI: 1.52‐15.27, P = .008). | |
| Young (2020) 21 |
Four hospitals in Singapore |
23 January to 3 February 2020 | 18 | CRP treated as a continuous variable, mg/L | Median CRP level was 65.6 (IQR: 47.5‐97.5) in patients that required supplemental O2 and 11.1 (IQR: 0.9‐19.1) in those that did not; no statistical comparison was undertaken. | |
| Deng (2020) 30 | Wuhan, China | 1 January 2020 to 21 February 2020 |
225 |
CRP treated as a continuous variable mg/L) | On admission, patients in the death group exhibited significantly higher CRP level (median: 109.25, IQR: 35.00‐170.28 mg/L vs median: 3.22 IQR: 1.04, 21.80 mg/L, P<.001). CRP levels remained high after treatment in the non‐survivors. | |
| Ferritin | ||||||
| Wu (2020) 20 |
Jinyintan Hospital, Wuhan, China |
25 December 2019, to 13 February 2020 | 201 | Serum ferritin >300 vss ≤300 ng/mL in a bivariate Cox regression model | Higher serum ferritin was associated with ARDS development (HR = 3.53, 95%CI: 1.52‐8.16, P = .003); the trend of an association with survival did not reach significance (HR = 5.28, 95%CI: 0.72‐38.48, P = .10). | |
| Zhou (2020) 31 |
Jinyintan Hospital and Wuhan Pulmonary Hospital, Wuhan, China |
25 December 2019, to 31 January 2020 | 191 | Serum ferritin >300 vs ≤300 ng/mL in a multivariate logistic regression model | Higher serum ferritin levels were associated with higher odds of death at the univariate analysis (OR = 9.10, 95%CI: 2.04‐40.58; P = .004); a multivariate analysis was not presented. | |
| Procalcitonin | ||||||
| Guan (2020) 16 |
552 hospitals in 30 provinces, autonomous regions, and municipalities in mainland China |
11 December 2019 – 31 January 2020 | 1099 | Elevated procalcitonin ≥0.5 ng/mL | Disease severity was associated with elevated procalcitonin; 13.7% (16/117) of severe cases vs 3.7% (19/516) of non‐severe cases presented with elevated procalcitonin (P < .001a). The primary composite endpoint (admission to an intensive care unit, use of mechanical ventilation, or death) was also associated with elevated procalcitonin (12/50, 24.0% vs 23/583, 3.9%, P < .001a). | |
| Huang (2020) 17 |
Jinyintan Hospital (Wuhan, China) |
16 December 2019, to 2 January 2020 | 41 | Elevated procalcitonin ≥0.5 ng/mL | 3/12 (25%) patients necessitating ICU care presented with elevated procalcitonin levels vs 0/27 non‐ICU patients. Overall, procalcitonin levels was higher in ICU vs non‐ICU patients (P = .031). | |
| Wang (2020) 19 |
Zhongnan Hospital, Wuhan, China |
1 January to 3 February 2020 | 138 | Elevated procalcitonin ≥0.05 ng/mL | 75% (27/36) of ICU patients presented with high procalcitonin vs 21.6% (22/102) of non‐ICU patients (P < .001). | |
| Zhou (2020) 31 |
Jinyintan Hospital and Wuhan Pulmonary Hospital, Wuhan, China |
25 December 2019, to 31 January 2020 | 191 | Procalcitonin treated as continuous variable (in ng/mL) in a multivariate logistic regression model | Higher serum procalcitonin levels were associated with higher odds of death at the univariate analysis (OR = 13.75, 95%CI: 1.81‐104.40; P = .011); a multivariate analysis was not presented. | |
| Arentz (2020) 28 | Evergreen Hospital, Washington State, USA | 20 February 2020, to 5 March 2020 | 21 ICU patients | Procalcitonin presented as a continuous variable (ng/mL) | Mean baseline procalcitonin was 1.8 (ranging between 0.12‐9.56 ng/mL), whereas the reference range was 0.15‐2.0 ng/mL | |
| Lippi (2020) 35 | Meta‐analysis of published studies | Studies published up to 3 March 2020 | 4 published articles | The definition of increased procalcitonin during the synthesis of studies was not declared. |
Increased procalcitonin values were associated with a nearly 5‐fold higher risk of severe infection (OR = 4.76; 95% CI: 2.74‐8.29, I2 = 34%) |
Abbreviations: ARDS, acute respiratory distress syndrome; IQR, interquartile range.
a
P values calculated by Terpos et al., on the basis of contingency tables (Pearson's chi‐square test) in articles that did not present formal statistical comparisons.