BACKGROUND: A patient's infectivity is determined by the presence of the virus in different body fluids, secretions, and excreta. The persistence and clearance of viral RNA from different specimens of patients with 2019 novel coronavirus disease (COVID-19) remain unclear. This study analyzed the clearance time and factors influencing 2019 novel coronavirus (2019-nCoV) RNA in different samples from patients with COVID-19, providing further evidence to improve the management of patients during convalescence. METHODS: The clinical data and laboratory test results of convalescent patients with COVID-19 who were admitted to from January 20, 2020 to February 10, 2020 were collected retrospectively. The reverse transcription polymerase chain reaction (RT-PCR) results for patients' oropharyngeal swab, stool, urine, and serum samples were collected and analyzed. Convalescent patients refer to recovered non-febrile patients without respiratory symptoms who had two successive (minimum 24 h sampling interval) negative RT-PCR results for viral RNA from oropharyngeal swabs. The effects of cluster of differentiation 4 (CD4)+ T lymphocytes, inflammatory indicators, and glucocorticoid treatment on viral nucleic acid clearance were analyzed. RESULTS: In the 292 confirmed cases, 66 patients recovered after treatment and were included in our study. In total, 28 (42.4%) women and 38 men (57.6%) with a median age of 44.0 (34.0-62.0) years were analyzed. After in-hospital treatment, patients' inflammatory indicators decreased with improved clinical condition. The median time from the onset of symptoms to first negative RT-PCR results for oropharyngeal swabs in convalescent patients was 9.5 (6.0-11.0) days. By February 10, 2020, 11 convalescent patients (16.7%) still tested positive for viral RNA from stool specimens and the other 55 patients' stool specimens were negative for 2019-nCoV following a median duration of 11.0 (9.0-16.0) days after symptom onset. Among these 55 patients, 43 had a longer duration until stool specimens were negative for viral RNA than for throat swabs, with a median delay of 2.0 (1.0-4.0) days. Results for only four (6.9%) urine samples were positive for viral nucleic acid out of 58 cases; viral RNA was still present in three patients' urine specimens after throat swabs were negative. Using a multiple linear regression model (F = 2.669, P = 0.044, and adjusted R = 0.122), the analysis showed that the CD4+ T lymphocyte count may help predict the duration of viral RNA detection in patients' stools (t = -2.699, P = 0.010). The duration of viral RNA detection from oropharyngeal swabs and fecal samples in the glucocorticoid treatment group was longer than that in the non-glucocorticoid treatment group (15 days vs. 8.0 days, respectively; t = 2.550, P = 0.013) and the duration of viral RNA detection in fecal samples in the glucocorticoid treatment group was longer than that in the non-glucocorticoid treatment group (20 days vs. 11 days, respectively; t = 4.631, P < 0.001). There was no statistically significant difference in inflammatory indicators between patients with positive fecal viral RNA test results and those with negative results (P > 0.05). CONCLUSIONS In brief, as the clearance of viral RNA in patients' stools was delayed compared to that in oropharyngeal swabs, it is important to identify viral RNA in feces during convalescence. Because of the delayed clearance of viral RNA in the glucocorticoid treatment group, glucocorticoids are not recommended in the treatment of COVID-19, especially for mild disease. The duration of RNA detection may relate to host cell immunity.
Adult ; Aged ; Betacoronavirus ; genetics ; Clinical Laboratory Techniques ; Coronavirus Infections ; diagnosis ; genetics ; rehabilitation ; Female ; Humans ; Male ; Middle Aged ; Pandemics ; Pneumonia, Viral ; genetics ; rehabilitation ; RNA, Viral ; genetics ; Real-Time Polymerase Chain Reaction ; Retrospective Studies

Background: A patient’s infectivity is determined by the presence of the virus in different body fluids, secretions, and excreta. The persistence and clearance of viral RNA from different specimens of patients with 2019 novel coronavirus disease (COVID-19) remain unclear. This study analyzed the clearance time and factors influencing 2019 novel coronavirus (2019-nCoV) RNA in different samples from patients with COVID-19, providing further evidence to improve the management of patients during convalescence. Methods: The clinical data and laboratory test results of convalescent patients with COVID-19 who were admitted to from January 20, 2020 to February 10, 2020 were collected retrospectively. The reverse transcription polymerase chain reaction (RT-PCR) results for patients’ oropharyngeal swab, stool, urine, and serum samples were collected and analyzed. Convalescent patients refer to recovered non-febrile patients without respiratory symptoms who had two successive (minimum 24 h sampling interval) negative RT-PCR results for viral RNA from oropharyngeal swabs. The effects of cluster of differentiation 4 (CD4)+ T lymphocytes, inflammatory indicators, and glucocorticoid treatment on viral nucleic acid clearance were analyzed. Results: In the 292 confirmed cases, 66 patients recovered after treatment and were included in our study. In total, 28 (42.4%) women and 38 men (57.6%) with a median age of 44.0 (34.0–62.0) years were analyzed. After in-hospital treatment, patients’ inflammatory indicators decreased with improved clinical condition. The median time from the onset of symptoms to first negative RT-PCR results for oropharyngeal swabs in convalescent patients was 9.5 (6.0–11.0) days. By February 10, 2020, 11 convalescent patients (16.7%) still tested positive for viral RNA from stool specimens and the other 55 patients’ stool specimens were negative for 2019-nCoV following a median duration of 11.0 (9.0–16.0) days after symptom onset. Among these 55 patients, 43 had a longer duration until stool specimens were negative for viral RNA than for throat swabs, with a median delay of 2.0 (1.0–4.0) days. Results for only four (6.9%) urine samples were positive for viral nucleic acid out of 58 cases; viral RNA was still present in three patients’ urine specimens after throat swabs were negative. Using a multiple linear regression model (F=2.669, P=0.044, and adjusted R²=0.122), the analysis showed that the CD4+ T lymphocyte count may help predict the duration of viral RNA detection in patients’ stools (t=-2.699, P=0.010). The duration of viral RNA detection from oropharyngeal swabs and fecal samples in the glucocorticoid treatment group was longer than that in the non-glucocorticoid treatment group (15 days vs 8.0 days, respectively; t=2.550, P=0.013) and the duration of viral RNA detection in fecal samples in the glucocorticoid treatment group was longer than that in the non-glucocorticoid treatment group (20 days vs 11 days, respectively; t=4.631, P <0.001). There was no statistically significant difference in inflammatory indicators between patients with positive fecal viral RNA test results and those with negative results (P >0.05). Conclusions In brief, as the clearance of viral RNA in patients’ stools was delayed compared to that in oropharyngeal swabs, it is important to identify viral RNA in feces during convalescence. Because of the delayed clearance of viral RNA in the glucocorticoid treatment group, glucocorticoids are not recommended in the treatment of COVID-19, especially for mild disease. The duration of RNA detection may relate to host cell immunity.

Objective: To discuss the effect of Gandou decoction (GDD) on the immune index of spleen in TX mice of Wilson's disease model. Method: The mice were divided into normal group, model group and GDD or tetrathiomolybdate(TM)treatment group, with 20 mice in each group. Each group was fed in various ways for 30 successive days. Normal group:10 normal DL mice were randomly selected and feed normally. Model group:20 TX mice were randomly selected and feed with 2 mL·kg^-1·d^-1ig saline by gavage twice per day. GDD or TM treatment group:80 TX mice were randomly selected and feed with 2 mL·kg^-1·d^-1 ig Gandou decoction 22,44,66 g·kg^-1 or tetrathiomolybdate by gavage twice per day. ICP-MS was used to compare the expressions of trace elements inside the mice's spleens, flow cytometry was applied to detect the mice T lymphocyte subsets of splenic tissue CD4⁺, CD8⁺, CD4⁺/CD8⁺, and Western blot was used to detect the expressions of interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), interleukin-8 (IL-8), interleukin-17 (IL-17) and interleukin-18 (IL-18). Result: Flow ICP-MS results showed that GDD can reduce Cu of mice's spleen, flow cytometry results showed that CD4⁺and CD8⁺in model group were increased than those in normal group (P<0.01), and CD4⁺/CD8⁺was decreased (P<0.01); compared with model group, CD4⁺and CD8⁺in middle and high-dose GDD groups were decreased (P<0.01), and CD4⁺/CD8⁺was increased. According to Western blot detection, compared with normal group, the expressions of IL-2, IL-8, IL-17, IL-18, TNF-α and IFN-γ in the model group were increased (P<0.01); compared with model group, the expressions of TNF-α, IFN-γ, IL-2, IL-8, IL-17 and IL-18 in the GDD middle and high or TM group were decreased (P<0.05, P<0.01). Compared with model group, the expressions of IL-2, IL-8, IL-17 and TNF-α in the GDD low were decreased (P<0.05). Conclusion: Spleen of TX mice shows the cellular immunity hyperfunction, which is mainly dominated by the negative immunoloregulation. GDD has a certain effect in regulating cellular immunity hyperfunctional state of TX mice, but it's difficult to thoroughly change the negative immune regulation.

Objective To observe distribution and antimicrobial resistance of pathogens from blood culture of chil-dren with leukemia,and study risk factors.Methods From September 2013 to November 2016,species and antimi-crobial resistance types of 131 strains of pathogens isolated from blood culture of 110 children in a pediatric hemato-logy ward were analyzed,childrens'clinical data were also analyzed statistically.Results 131 strains(5.23%)of pathogens were isolated from 2 505 blood culture specimens,gram-negative bacilli and gram-positive cocci accounted for 52.67% and 43.51% respectively,the top 3 pathogens were Escherichia coli(15.27%),Klebsiella pneumoniae (15.27%),and Staphylococcus hominis(12.98%). Gram-negative bacilli were highly resistant to ampicillin,ce-fazolin,ceftriaxone,and ampicillin/sulbactam,but sensitive to amikacin,cefoperazone/sulbactam,piperacillin/tazobactam,and carbapenems;gram-positive cocci had higher resistance to penicillin,oxacillin,erythromycin,and clindamycin,but were sensitive to tigecycline,linezolid,vancomycin,and quinupristin/dalfopristin. Univariate analysis showed that mixed infection,diarrhea,Pseudomonasaeruginosa infection,and Acinetobacterbaumannii in-fection were related to mortality due to bloodstream infection in children with leukemia.Conclusion Pathogens cau-sing bloodstream infection in children with leukemia is widely distributed,antimicrobial resistance rate is high,it is very im-portant to take active precaution and rational treatment according to antimicrobial susceptibility testing result.