Exploration of turn-positive RT-PCR results and factors related to treatment outcome in COVID-19: A retrospective cohort study

Figures & data

Table 1. Characteristics and baseline of participants.

Characteristics	Recurrent Group (n = 40)	Recovered Group (n = 29)	Un-recovered Group (n = 47)	p Value
Age (years), mean ± SD	39.85 ± 14.88	42.21 ± 13.92	47.45 ± 16.95	0.07
Gender
Male, n (%)	7 (17.5%)	8 (27.6%)	14 (29.8)	0.391
Female, n (%)	33 (82.5%)	21 (72.4)	33 (70.2)
Complete Blood Count
WBC, 10^9/L	5.28 ± 1.56	5.05 ± 1.97	5.33 ± 2.15	0.823
Neutrophils, 10^9/L	3.16 ± 1.41	2.96 ± 1.79	3.09 ± 1.61	0.882
Lymphocytes, 10^9/L	1.58 ± 0.62	1.56 ± 0.58	1.66 ± 0.85	0.821
RBC, 10^12/L	4.20 ± 0.49	4.32 ± 0.46	4.28 ± 0.55	0.603
HB, g/L	125.53 ± 16.20	129.19 ± 16.35	130.09 ± 15.47	0.392
PLT, 10^9/L	230.75 ± 79.92	206.16 ± 69.29	199.13 ± 64.28	0.110
Liver Function Test
ALT, U/L	24.83 ± 23.55	22.62 ± 19.75	23.96 ± 17.38	0.905
AST, U/L	23.80 ± 12.98	23.25 ± 13.57	24.53 ± 10.08	0.886
TBIL, μmol/L	10.29 ± 7.12	9.72 ± 3.53	9.55 ± 4.83	0.814
DBIL, μmol/L	3.08 ± 1.90	3.22 ± 1.15	3.20 ± 1.70	0.925
ALB, g/L	40.52 ± 3.69	40.06 ± 3.62	40.14 ± 4.55	0.869
Urea, mmol/L	4.52 ± 2.58	4.13 ± 1.18	4.21 ± 1.42	0.521
Cr, μmol/L	62.50 ± 56.53	58.14 ± 14.04	58.98 ± 16.46	0.854
Urea/Cr, ratio	0.078 ± 0.020	0.072 ± 0.019	0.073 ± 0.023	0.380
Coagulation Test
PT, sec	11.72 ± 0.68	11.68 ± 0.53	11.29 ± 0.73	0.006
APTT, sec	29.48 ± 1.97	29.38 ± 3.42	29.25 ± 2.46	0.917
D-Dimer, mg/L	0.82 ± 1.09	0.98 ± 1.61	0.52 ± 0.72	0.202
Cell-mediated Immunity
CD3+/μL	1018.11 ± 478.35	1079.80 ± 524.23	969.15 ± 477.05	0.632
CD4+/μL	565.00 ± 285.05	646.55 ± 301.64	554.60 ± 303.81	0.390
CD8+/μL	361.52 ± 188.88	380.43 ± 224.87	354.56 ± 190.61	0.857
CD4+/CD8+, ratio	1.70 ± 0.49	1.91 ± 0.67	1.73 ± 0.78	0.379
CD19+/μL	173.69 ± 98.99	226.46 ± 117.04	200.82 ± 148.56	0.226
CD16+&CD56+/μL	180.00 ± 119.35	174.19 ± 81.26	215.43 ± 136.64	0.242
Humoral Immunity
IgM, g/L	1.09 ± 0.34	1.26 ± 0.61	1.06 ± 0.44	0.145
IgG, g/L	12.00 ± 3.22	12.06 ± 3.05	11.86 ± 2.95	0.956
C3 complement, g/L	0.87 ± 0.15	0.83 ± 0.15	0.86 ± 0.17	0.605
C4 complement, g/L	0.26 ± 0.08	0.22 ± 0.08	0.24 ± 0.09	0.221
CT
Abnormal/n*	39/40	29/29	45/47	0.785

Note: SD; WBC: white blood cell; HB: hemoglobin;PLT: platelet;ALT: alanine transaminase;AST: aspartate aminotransferase;TBIL: total bilirubin;DBIL: direct bilirubin;ALB: albumin; PT: prothrombin time;APTT: activated partial thromboplastin time;CD: cluster of differentiation; CT: computed tomography.

Table 2. Intra group comparison of recurrent group.

Characteristics	Baseline (n = 40)	Negative (n = 40)	Positive (n = 40)	P value
Complete Blood Count
WBC, 10^9/L	5.28 ± 1.56	6.41 ± 2.07	5.59 ± 1.30	0.009
Neutrophils, 10^9/L	3.16 ± 1.41	3.97 ± 1.99	3.21 ± 1.09	0.035
Lymphocytes, 10^9/L	1.58 ± 0.62	1.77 ± 0.55	1.72 ± 0.43	0.273
RBC, 10^12/L	4.20 ± 0.49	4.02 ± 0.42	4.02 ± 0.49	0.125
HB, g/L	125.53 ± 16.20	121.29 ± 12.86	119.78 ± 24.19	0.353
PLT, 10^9/L	230.75 ± 79.92	241.74 ± 67.46	232.38 ± 49.41	0.730
Liver Function Test
ALT, U/L	24.83 ± 23.55	35.00 ± 30.93	34.88 ± 24.32	0.147
AST, U/L	23.80 ± 12.98	22.53 ± 8.93	26.53 ± 11.32	0.268
TBIL, μmol/L	10.29 ± 7.12	12.07 ± 5.33	10.28 ± 4.40	0.276
DBIL, μmol/L	3.08 ± 1.90	3.08 ± 1.51	2.99 ± 2.50	0.973
ALB, g/L	40.52 ± 3.69	39.24 ± 3.25	40.46 ± 2.64	0.139
Urea, mmol/L	4.52 ± 2.58	4.29 ± 2.17	4.27 ± 2.37	0.873
Cr, μmol/L	62.50 ± 56.53	54.94 ± 37.64	58.48 ± 40.43	0.760
Urea/Cr, ratio	0.078 ± 0.020	0.082 ± 0.022	0.077 ± 0.021	0.513
Coagulation Test
PT, sec	11.72 ± 0.68	10.57 ± 0.38	10.50 ± 0.44	0.000
APTT, sec	29.48 ± 1.97	26.85 ± 1.87	27.34 ± 2.18	0.000
D-Dimer, mg/L	0.82 ± 1.09	0.54 ± 0.43	0.52 ± 0.49	0.140
Cell-mediated Immunity
CD3+/μL	1018.11 ± 478.35	1228.08 ± 300.22	1262.44 ± 295.75	0.007
CD4+/μL	565.00 ± 285.05	663.65 ± 200.09	711.41 ± 194.51	0.017
CD8+/μL	361.52 ± 188.88	477.54 ± 129.98	462.30 ± 121.81	0.001
CD4+/CD8+, ratio	1.70 ± 0.49	1.48 ± 0.39	1.62 ± 0.33	0.005
CD19+/μL	173.69 ± 98.99	195.80 ± 69.13	189.49 ± 51.61	0.114
CD16+&CD56+/μL	180.00 ± 119.35	213.96 ± 97.20	209.37 ± 79.60	0.198
Humoral Immunity
IgM, g/L	1.09 ± 0.34	1.28 ± 0.50	1.23 ± 0.54	0.152
IgG, g/L	12.00 ± 3.22	13.37 ± 2.91	11.46 ± 3.00	0.018
C3 complement, g/L	0.87 ± 0.15	0.88 ± 0.15	0.87 ± 0.14	0.882
C4 complement, g/L	0.26 ± 0.08	0.21 ± 0.07	0.20 ± 0.06	0.001
CT
Abnormal/n*	39/40	24/40	10/40	0.000

Note: SD; WBC: white blood cell; HB: hemoglobin;PLT: platelet;ALT: alanine transaminase;AST: aspartate aminotransferase;TBIL: total bilirubin;DBIL: direct bilirubin;ALB: albumin; PT: prothrombin time;APTT: activated partial thromboplastin time;CD: cluster of differentiation; CT: computed tomography.

Table 3. Risk factors associated with clinical outcomes.

Laboratory test	Univariable analysis		Multivariable analysis
	OR (95%CI)	p value	OR (95%CI)	p value
Age (years)	1.022 (0.991–1.054)	0.166
Gender (vs male)	1.114 (0.399–3.109)	0.837
Complete Blood Count
WBC, 10^9/L	1.022 (0.782–1.335)	0.873
Neutrophils, 10^9/L	0.961 (0.708–1.305)	0.798
Lymphocytes, 10^9/L	1.725 (0.710–4.189)	0.229
RBC, 10^12/L	0.714 (0.289–1.764)	0.466
HB, g/L	0.989 (0.957–1.023)	0.527
PLT, 10^9/L	1.000(0.994–1.006)	0.997
Liver Function Test
ALT, U/L	0.996 (0.976–1.017)	0.704
AST, U/L	0.991 (0.949–1.036)	0.699
TBIL, μmol/L	0.977 (0.886–1.077)	0.641
DBIL, μmol/L	0.955 (0.725–1.259)	0.745
ALB, g/L	0.997 (0.924–1.076)	0.944
Urea, mmol/L	1.109 (0.707–1.741)	0.652
Cr, μmol/L	0.995 (0.958–1.033)	0.790
Urea/Cr, ratio	3803.25(0–7.7*10^12)	0.451
Coagulation Test
PT, sec	1.978 (0.708–5.532)	0.193
APTT, sec	0.944 (0.745–1.196)	0.631
D-Dimer, mg/L	1.170 (0.614–2.227)	0.633
Cell-mediated Immunity
CD3+/μL	0.999 (0.997–1.001)	0.239	0.953 (0.922–0.986)	0.005*
CD4+/μL	1.000 (0.997–1.002)	0.769	1.037 (1.009–1.066)	0.010*
CD8+/μL	0.998 (0.995–1.001)	0.261	1.051 (1.007–1.096)	0.024*
CD4+/CD8+, ratio	1.128 (0.533–2.388)	0.753	1.396 (0.062–31.477)	0.834
CD19+/μL	1.006 (1.000–1.013)	0.052	1.042 (1.018–1.067)	0.001*
CD16+&CD56+,/μL	1.000 (0.995–1.004)	0.851	0.997 (0.987–1.008)	0.618
Humoral Immunity
IgM, g/L	0.036 (0.004–0.309)	0.002	0.001 (0.000–0.061)	0.001*
IgG, g/L	0.717 (0.539–0.954)	0.023	0.801 (0.512–1.256)	0.334
C3, g/L	0.371 (0.013–10.436)	0.560	0.000 (0.000–0.075)	0.009*
C4, g/L	1.3*10^5(0.583–3.1*10^10)	0.061	2.5*10^12 (3467–1.7*10^21)	0.006*
CT (vs positive)	0.302 (0.078–1.170)	0.083	0.010 (0.000–0.317)	0.009*

Note: SD; WBC: white blood cell; HB: hemoglobin;PLT: platelet;ALT: alanine transaminase;AST: aspartate aminotransferase;TBIL: total bilirubin;DBIL: direct bilirubin;ALB: albumin; PT: prothrombin time;APTT: activated partial thromboplastin time;CD: cluster of differentiation; CT: computed tomography.