Manifestations of COVID-19 infection in patients with systemic rheumatic disease with COVID-19 (n=52) and age, sex and diagnosis date matched comparators (n=104)
| Characteristic | Rheumatic disease (n=52) | No rheumatic disease (n=104) | P value |
| Symptoms at initial presentation | |||
| Cough | 35 (67) | 76 (74) | 0.40 |
| Fever | 34 (65) | 66 (64) | 0.87 |
| Myalgia | 26 (50) | 40 (39) | 0.18 |
| Malaise | 22 (42) | 35 (34) | 0.31 |
| Shortness of breath | 21 (40) | 49 (48) | 0.40 |
| Sore throat | 19 (37) | 32 (31) | 0.49 |
| Diarrhoea | 18 (35) | 26 (25) | 0.22 |
| Headache | 15 (29) | 22 (22) | 0.50 |
| Rhinorrhoea | 14 (27) | 27 (26) | 0.92 |
| Chest pain | 6 (12) | 15 (15) | 0.60 |
| Anosmia | 4 (8) | 16 (16) | 0.17 |
| Abdominal pain | 3 (6) | 9 (9) | 0.51 |
| Confusion | 1 (2) | 7 (7) | 0.27 |
| Laboratory values*† | |||
| White blood cell count, K/µL (n=30/82) | 6.1 (5.1 to 8.5) | 5.6 (4.3 to 7.2) | 0.03 |
| Absolute lymphocyte count, K/µL (n=30/81) | 0.9 (0.7 to 1.5) | 0.9 (0.6 to 1.3) | 0.39 |
| Haemoglobin, g/dL (n=31/83) | 12.8 (11.5 to 13.6) | 13.4 (12.1 to 14.2) | 0.23 |
| Platelets, K/µL (n=31/82) | 206 (172 to 249) | 187 (153 to 229) | 0.34 |
| D-dimer, ng/mL (n=22/64) | 955 (550 to 2041) | 1059 (643 to 1650) | 0.57 |
| Ferritin, µg/L (n=22/62) | 513 (256 to 952) | 419 (201 to 1063) | 0.54 |
| AST, U/L (n=26/73) | 42 (28 to 59) | 33 (28 to 68) | 0.58 |
| ALT, U/L (n=26/73) | 25 (17 to 46) | 27 (18 to 48) | 0.18 |
| Creatinine, mg/dL (n=33/79) | 1.0 (0.8 to 1.4) | 1.0 (0.8 to 1.1) | 0.33 |
| ESR, mm/hour (n=20/51) | 49 (36 to 62) | 47 (27 to 84) | 0.75 |
| CRP, mg/L (n=23/60) | 95.6 (51.9 to 178.4) | 60.4 (48.8 to 110.5) | 0.11 |
| Peak ferritin, µg/L (n=22/57) | 739 (379 to 1402) | 1196 (433 to 2347) | 0.04 |
| Peak ESR, mm/hour (n=20/49) | 69 (36 to 121) | 85 (54 to 124) | 0.47 |
| Peak CRP, mg/L (n=26/67) | 176 (52 to 262) | 143 (61 to 212) | 0.40 |
| Peak D-dimer, ng/mL (n=22/61) | 1251 (550 to 4000) | 1446 (884 to 2972) | 0.83 |
Data are represented by median (IQR) or number (percentage).
Bold signifies P<0.05.
*Laboratory values represent those closest to diagnosis or hospital admission, unless otherwise indicated. White cell count and absolute lymphocyte count from one patient excluded due to outlier from underlying comorbidity. Reference ranges: white cell count: 4.5–11.0 K/uL; absolute lymphocyte count: 1.0–4.8 K/uL; haemoglobin: 13.5–17.5 g/dL; platelets: 150–400 K/µL; D-dimer: <500 ng/mL; ferritin: 20–300 µg/L; AST: 9–32 U/L (women), 10–40 U/L (men); ALT: 7–33 U/L (women), 10–55 U/L (men); creatinine: <1.1 mg/dL; ESR: <13 mm/hour; CRP: <8 mg/L.
†For each lab value, N for cases/comparators is given in parentheses since not all patients had all tests performed.
ALT, alanine aminotransferase; AST, aspartate aminotransferase; CRP, C reactive protein; ESR, erythrocyte sedimentation rate; K/µL, thousands per microlitre; Ref, reference range.