Table 1 Demographic characteristics of the studied population and laboratory findings at admission

Age (years)^a

64.0 (58.0–66.0)

59.5 (50.0–64.5)

0.2725

Dead – N(%)

0 (0)

12 (42.8)

0.1329

Male gender – N(%)

4 (80.0)

22 (78.6)

> 0.999

 - Never smoked

0 (0)

24 (85.7)

0.0005^§

 - Former smoker

5 (100)

3 (10.7)

0.0002^§

 - Current smoker

0 (0)

1 (3.6)

> 0.999

 - Any

5 (100)

14 (50.0)

0.0574

 - Arterial hypertension

2 (40.0)

6 (21.4)

0.5736

 - Chronic heart disease

2 (40.0)

3 (10.7)

0.1546

 - Cerebrovascular disease

0 (0)

1 (3.6)

> 0.999

 - Chronic obstructive lung disease

0 (0)

1 (3.6)

> 0.999

 - Lung transplant

3 (60.0)

0 (0)

0.0018^§

 - Diabetes mellitus type II

1 (20.0)

2 (7.1)

0.3996

 - Cancer

1 (20.0)

1 (3.6)

0.2841

 - Immunosuppression

4 (80.0)

2 (7.1)

0.0017^§

 - Fever

5 (100)

27 (96.4)

> 0.999

 - Dyspnea, cough

1 (20.0)

28 (100)

0.0001^§

 - Diarrhea, nausea

2 (40.0)

2 (7.1)

0.0993

 - Dysgeusia, anosmia

1 (20.0)

0(0)

0.1515

Days between symptoms onset and hospitalization^a

7.0 (3.0–11.0)

6.0 (4.0–9.0)

0.9589

Days in CPAP prior intubation^a

–

2.0 (1.0–6.5)

na

Days between symptoms onset and BAL sampling^a

8.0 (4.0–12.0)

25.0 (20.0–30.0)

0.6852

SOFA score^ad

–

12.0 (8.0–13.0)

na

 - PaO₂/FiO₂ ratio

333.4 (195.5–379.1)

121.0 (97.5–157.5)

0.0060^§

 - White cell count (cells·ml^− 1)

7720.0 (4920.0–11,890.0)

13,700.0 (9400.0–16,810.0)

0.0379^§

 - Lymphocyte count (cells·ml^− 1)

900.0 (470.0–1990.0)

1130.0 (760.0–1675.0)

0.5807

 - Hemoglobin (cells·ml⁻¹)

10.7 (9.8–12.8)

10.05 (9.2–10.8)

0.2997

 - Platelet count (cells·ml^− 1)

278.0 (158.0–368.0)

353.0 (176.0–361.0)

0.9586

 - LDH (mU ml^− 1)

269.0 (171.5–339.0)

414.5 (419.5–547.8)

0.0169^§

 - CK (mU ml^− 1)

120.0 (46.0–582.5)

66.5 (32.5–419.8)

0.5368

 - D-dimer (ug l⁻¹)

1077.0 (689.0–1465.0)

3299.0 (1599.0–5497.0)

> 0.999

 - Ferritin (ng ml^− 1)

1191.5 (475.3–1928.0)

1413.0 (298.8–2534.0)

0.8081

 - Albumin (g l^− 1)

3.1 (2.4–3.6)

2.0 (2.0–2.1)

0.0015^§

 - CRP (mg dl^− 1)

11.3 (3.2–12.1)

36.1 (15.4–137.6)

0.0228^§

 - Procalcitonin (ng ml^− 1)

0.1 (0.1–1.1)

0.4 (0.3–1.0)

0.2135

 - Serum IL6 (ng l⁻¹)^b

41.1 (13.4–72.5)

476.5 (110.6–1636.0)

0.0102^§

Bacterial co-infections - N(%)^c

2 (40.0)

21 (75.0)

0.2911

Fungal co-infections - N(%)^c

0 (0)

4 (14.3)

0.5997

Viral co-infections - N(%)^c

0 (0)

1 (3.6)

> 0.999