Clinical Characteristics in Patients with Redetected Positive RNA Test After Recovery from Foreign-Imported COVID-19 Cases in Xi’an, China

Figures & data

Figure 1 A flow chart of management for foreign-imported COVID-19 patients.

Table 1 Demographic Characteristics of the Imported COVID-19 Cases

Variables	Patients (N=137)
Age (years)
Mean (SD)	37.8±11.4
IQR	38 (29–46)
Range, n (%)	8–68
<18	2 (1.4%)
18–24	17 (12.4%)
25–49	94 (68.6%)
50–64	23 (16.7%)
≥65	1 (0.7%)
Sex, n (%)
Female	14 (10.2%)
Male	123 (89.8%)
From countries, n (%)
Uzbekistan	28 (20.4%)
Singapore	17 (12.4%)
Germany	15 (10.9%)
United Arab Emirates	14 (10.2%)
Kazakhstan	12 (8.7%)
Pakistan	12 (8.7%)
Belgium	6 (4.3%)
Spain	5 (3.6%)
Azerbaijan	4 (2.9%)
Japan	4 (2.9%)
Portuguesa	4 (2.9%)
United States of America	3 (2.1%)
Russia	3 (2.1%)
Sudan	2 (1.4%)
United Kingdom	1 (0.7%)
Cambodia	1 (0.7%)
Sweden	1 (0.7%)
France	1 (0.7%)
Nigeria	1 (0.7%)
Canada	1 (0.7%)
Philippines	1 (0.7%)
Bolivia	1 (0.7%)
Clinical outcome, n (%)
Discharged	137 (100%)
Died	0
Repositive patients after discharge, n (%)	27 (19.7%)

Abbreviation: IQR, interquartile range.

Table 2 Comparison of Clinical Characteristics on the First Admission Between COVID-19 Patients with Non-Positive and Positive Retest Results After Discharge

Variables	Total (N = 137)	Non-Positive Retest (n= 110)	Positive Retest (n= 27)	χ^2 or t value	P value
Age (year)	38 (29–46)	40 (30–47)	32 (24–42)	2.016	0.052
Gender, n (%)				0.029	0.864
Male	123 (89.8%)	99 (90%)	24 (88.8%)
Female	14 (10.2%)	11 (10.0%)	3 (11.1%)
BMI (kg/m^2)	2.38±0.33	2.38±0.33	2.34±0.34	0.594	0.554
Comorbidities, n (%)	21 (15.3%)	16 (14.5%)	5 (18.5%)	0.264	0.608
Hypertension	10 (7.3%)	8 (7.3%)	2 (7.4%)	0.001	0.981
Hepatic adipose infiltration	4 (2.9%)	2 (1.8%)	2 (7.4%)	2.389	0.122
Diabetes	3 (2.2%)	3 (2.7%)	0 (0%)	0.753	0.386
Respiratory system diseases	3 (2.2%)	2 (1.8%)	1 (3.7%)	0.360	0.549
Coronary heart disease	1 (0.7%)	1 (0.9%)	0	0.360	0.549
Classification on admission, n (%)
Asymptomatic	67 (48.9%)	57 (51.8%)	10 (37%)	1.895	0.169
Mild	32 (23.3%)	23 (20.9%)	9 (33.1%)	1.869	0.172
Moderate	37 (27.0%)	29 (26.4%)	8 (29.6%)	0.117	0.732
Severe	1 (0.7%)	1 (0.9%)	0	0.247	0.619
Critical		0	0	NA	NA
Initial symptoms, n (%)
Cough	26 (18.9%)	19 (17.3%)	7 (25.9%)	1.056	0.304
Fever	31 (22.6%)	24 (21.8%)	7 (25.9%)	0.209	0.648
Sore throat	20 (14.5%)	15 (13.6%)	5 (18.5%)	0.414	0.520
Diarrhoea	6 (4.3%)	5 (4.5%)	1 (3.7%)	0.037	0.848
Stuffy nose	8 (5.8%)	5 (4.5%)	3 (11.1%)	1.700	0.192
Shortness of breath	4 (2.9%)	4 (3.6%)	0	1.011	0.315
Rhinorrhoea	3 (2.2%)	1 (0.9%)	2 (7.4%)	4.274	0.039
Fatigue	10 (7.3%)	9 (8.1%)	1 (3.7%)	0.642	0.423
Chest pain	2 (1.5%)	2 (1.8%)	0 (0%)	0.498	0.480
Headache and mental disorder	4 (2.9%)	4 (3.6%)	0	1.011	0.315
Muscle ache	2 (1.5%)	2 (1.8%)	0 (0%)	0.498	0.48
Days from onset of symptoms to admission (days)	1.8±0.56	1.9±6.7	1.6±5.7	0.204	0.839
Number of nucleic acid tests, n (%)				2.564	0.277
1	18 (13.1%)	12 (10.9%)	6 (22.2%)	2.431	0.119
2	75 (54.7%)	61 (55.4%)	14 (51.8%)	0.114	0.736
≥3	44 (32.1%)	37 (33.6%)	7 (25.9%)	0.591	0.442
Time from hospitalization to confirmation (days)				4.617	0.032
≤3	93 (67.8%)	70 (63.6%)	23 (85.1%)
>3	44 (32.2%)	40 (36.3%)	4 (14.9%)
Hospital stay (days)	16.1±8.9	16.3±9.1	15.2±7.8	0.576	0.566
Treatment in hospital, n (%)
Antiviral drugs	81 (59.1%)	67 (60.9%)	14 (51.8%)	0.736	0.391
Taking Chinese medicine	106 (77.4%)	88 (80%)	18 (66.6%)	2.201	0.138

Abbreviation: BMI, body mass index.

Table 3 Comparison of Laboratory Findings and Chest CT Findings on the First Admission Between the COVID-19 Patients with Non-Positive and Positive Retest Results After Discharge

Variables	Non-Positive Retest (n = 110)	Positive Retest (n= 27)	χ^2 or t value	P value
Routine blood test
White blood cell count (× 10^9/L)	6.7±1.8	6.4±1.39	0.993	0.148
Neutrophil count (×10^9/L)	4.1±1.4	3.5±0.93	1.895	0.06
Neutrophil percentage (%)	59.1±10.3	54.1±5.6	2.394	0.018
Lymphocyte count (× 10^9/L)	2.18±1.79	2.16±0.45	0.046	0.963
Lymphocyte percentage (%)	30.2±9.72	34.25±5.36	2.086	0.039
Monocyte count (× 10^9/L)	0.548±0.193	0.545±0.153	0.085	0.932
Monocyte percentage (%)	8.04±2.41	8.48±2.4	0.86	0.391
Haemoglobin (g/L)	149.8±16.4	151±24.7	0.489	0.626
Platelet (× 10^9/L)	231.2±65.7	240±60.7	0.684	0.495
COVID-19-specific antibody, n (%)
IgM (+)	10 (9.1%)	3 (11.1%)	0.103	0.748
IgG (+)	35 (31.8%)	9 (33.3%)	0.023	0.880
IgM (+) and IgG (+)	29 (26.3%)	8 (29.6%)	0.117	0.732
IgM (-) and IgG (-)	36 (32.7%)	7 (25.9%)	0.466	0.495
Chest CT finding, n (%)
The lesion range of chest CT
Bilateral lung	20 (18.2%)	6 (22.2%)	0.230	0.631
Unilateral pneumonia	19 (17.3%)	6 (22.2%)	0.356	0.551
Normal	71 (64.5%)	15 (55.5%)	0.750	0.387
Type of lesion
Pure GGO	7 (6.3%)	5 (18.5%)	4.008	0.045
GGO with reticular and/or interlobular    septal thickening	5 (4.5%)	2 (7.4%)	0.366	0.545
GGO with consolidation	11 (10%)	1 (3.7%)	1.075	0.300
Consolidation	3 (2.7%)	1 (3.7%)	0.073	0.787

Abbreviations: CT, computed tomography; GGO, ground-glass opacity.

Table 4 Comparison of Laboratory Data and Chest CT Findings Between Non-Positive and Positive Retest COVID-19 Patients When Quarantine Ended

Variables	Non-Positive Retest (n = 110)	Positive Retest (n = 27)	χ^2 or t value	P value
Routine blood test
White blood cell count (× 10^9/L)	6.46±1.86	6.42±1.39	0.113	0.910
Neutrophil count (× 10^9/L)	3.68±1.40	3.51±0.93	0.601	0.450
Neutrophil percentage (%)	55.10±8.96	54.13±5.63	0.536	0.593
Lymphocyte count (× 10^9/L)	2.15±0.733	2.16±0.453	0.079	0.918
Lymphocyte percentage (%)	33.88±8.78	34.25±5.36	0.212	0.779
Monocyte count (× 10^9/L)	0.496	0.521	0.768	0.424
Monocyte percentage (%)	8.01±2.81	8.488	0.811	0.419
Haemoglobin (g/L)	151±17.5	149±15.5	0.722	0.472
Platelet (× 10^9/L)	238.8±63.4	244.6±55.8	0.433	0.642
COVID-19-specific antibody
IgM (+)	9 (8.1%)	3 (11.1%)	0.233	0.629
IgG (+)	34 (30.9%)	9 (33.3%)	0.059	0.808
IgM (+) and IgG (+)	39 (35.5%)	8 (29.6%)	0.326	0.568
IgM (-) and IgG (-)	28 (25.5%)	7 (25.9%)	0.003	0.960
Chest CT imaging, n (%)
Transient progression	2 (1.8%)	2 (7.4%)	2.389	0.112
Sustained remission	19 (17.2%)	2 (7.4%)	1.626	0.202
No change	27 (24.5%)	9 (33.3%)	0.864	0.353
Normal	62 (55.5%)	14 (51.8%)	0.179	0.673

Abbreviation: CT, computed tomography.

Table 5 Baseline Characteristics of Positive Retest Patients at First Hospitalization and Readmission

Features	First Hospitalization (n = 27)	Readmission (n = 27)	χ^2 or t value	P value
Routine blood test
White blood cell count (×10^9/L)	6.65±1.84	6.42±1.39	0.523	0.604
Neutrophil count (× 10^9/L)	4.08±1.58	3.51±0.94	1.632	0.109
Neutrophil percentage (%)	59.9±9.2	54.1±5.6	2.78	0.008
Lymphocyte count (× 10^9/L)	1.88±0.49	2.17±0.453	2.216	0.031
Lymphocyte percentage (%)	29.31±7.32	34.25±5.36	2.834	0.007
Monocyte count (× 10^9/L)	0.544±0.152	0.521±0.143	0.570	0.571
Monocyte percentage (%)	8.75±3.49	8.48±2.41	0.318	0.752
Haemoglobin (g/L)	151.7±24.7	149.1±15.5	0.475	0.637
Platelet (× 10^9/L)	240.7±60.7	144.5±55.8	0.245	0.807
COVID-19 specific antibody, n (%)
IgM (+)	3 (11.1%)	2 (7.4%)	0.220	0.639
IgG (+)	9 (33.3%)	12 (44.4%)	0.701	0.402
IgM (+) and IgG (+)	8 (29.6%)	6 (22.2%)	0.386	0.535
IgM (-) and IgG (-)	7 (25.9%)	7 (25.9%)	0	1
Treatment in hospital, n (%)
Antiviral drugs	14 (51.9%)	13 (48.1%)	0.074	0.785
Taking Chinese medicine	18 (66.7%)	18 (66.7%)	0	1

Table 6 Clinical Characteristics of Positive Retest Patients on Readmission

Variables	Patients (n=27)
Age (years)	32 (24–42)
Sex, n (%)
Female	3 (11.1%)
Male	24 (88.9%)
Symptoms, n (%)
Cough	0
Fever	0
Sore throat	2 (7.4%)
Diarrhoea	0
Stuffy nose	1 (3.7%)
Chest tightness	1 (3.7%)
Shortness of breath	0
Rhinorrhoea	0
Fatigue	0
Chest pain	0
Headache and mental disorder symptoms	0
Muscle ache	0
Chest CT imaging, n (%)
Transient progression	2 (7.4%)
Sustained remission	2 (7.4%)
No change	9 (33.3%)
Normal	14 (51.9%)

Abbreviation: CT, computed tomography.