A Peptide-Based Magnetic Chemiluminescence Enzyme Immunoassay for Serological Diagnosis of Coronavirus Disease 2019.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel ß-coronavirus, causes severe pneumonia and has spread throughout the globe rapidly. The disease associated with SARS-CoV-2 infection is named coronavirus disease 2019 (COVID-19). To date, real-time reverse-transcription polymerase chain reaction (RT-PCR) is the only test able to confirm this infection. However, the accuracy of RT-PCR depends on several factors; variations in these factors might significantly lower the sensitivity of detection. METHODS: In this study, we developed a peptide-based luminescent immunoassay that detected immunoglobulin (Ig)G and IgM. The assay cutoff value was determined by evaluating the sera from healthy and infected patients for pathogens other than SARS-CoV-2. RESULTS: To evaluate assay performance, we detected IgG and IgM in the sera from confirmed patients. The positive rate of IgG and IgM was 71.4% and 57.2%, respectively. CONCLUSIONS: Therefore, combining our immunoassay with real-time RT-PCR might enhance the diagnostic accuracy of COVID-19.

The clinical and immunological features of pediatric COVID-19 patients in China.

In December 2019, the corona virus disease 2019 (COVID-19) caused by novel coronavirus (SARS-CoV-2) emerged in Wuhan, China and rapidly spread worldwide. Few information on clinical features and immunological profile of COVID-19 in paediatrics. The clinical features and treatment outcomes of twelve paediatric patients confirmed as COVID-19 were analyzed. The immunological features of children patients was investigated and compared with twenty adult patients. The median age was 14.5-years (range from 0.64 to 17), and six of the patients were male. The average incubation period was 8 days. Clinically, cough (9/12, 75%) and fever (7/12, 58.3%) were the most common symptoms. Four patients (33.3%) had diarrhea during the disease. As to the immune profile, children had higher amount of total T cell, CD8+ T cell and B cell but lower CRP levels than adults (P < 0.05). Ground-glass opacity (GGO) and local patchy shadowing were the typical radiological findings on chest CT scan. All patients received antiviral and symptomatic treatment and the symptom relieved in 3-4 days after admitted to hospital. The paediatric patients showed mild symptom but with longer incubation period. Children infected with SARS-CoV-2 had different immune profile with higher T cell amount and low inflammatory factors level, which might ascribed to the mild clinical symptom. We advise that nucleic acid test or examination of serum IgM/IgG antibodies against SARS-CoV-2 should be taken for children with exposure history regardless of clinical symptom.

Antibody responses to SARS-CoV-2 in patients with COVID-19.

We report acute antibody responses to SARS-CoV-2 in 285 patients with COVID-19. Within 19 days after symptom onset, 100% of patients tested positive for antiviral immunoglobulin-G (IgG). Seroconversion for IgG and IgM occurred simultaneously or sequentially. Both IgG and IgM titers plateaued within 6 days after seroconversion. Serological testing may be helpful for the diagnosis of suspected patients with negative RT-PCR results and for the identification of asymptomatic infections.

The natural history of chronic hepatitis B: a retrospective study.

OBJECTIVE: To clarify the natural history of chronic hepatitis B so as to evaluate its long-term therapeutic outcome of the patients and the efficacy of antiviral drugs. METHODS: A cohort of 183 biopsy-proven chronic hepatitis B patients (mean age of 31.75+/-8.03 years, male/female ratio: 152:31) and 247 controls were followed up retrospectively for 11.81+/-4.08 years. This study was focused on long-term clinical outcome including the rates of liver cirrhosis, hepatocellular carcinoma and death, apart from the long-term effect of antiviral drugs and prognostic factors. RESULTS: In the 183 chronic hepatitis B patients, 22 (12.02%) developed liver cirrhosis, 12 (6.56%) developed hepatocellular carcinoma, and 20 (10.93%) died. The 5-, 10- and 15-year survival rates were 97.27%, 91.62%, and 84.47%, respectively. The 5-, 10- and 15-year incidence rates of HCC were 0, 3.19%, and 11.56%, respectively. In the 247 controls, 6 (2.43%) died; none of them developed cirrhosis or HCC. The rates of death, liver cirrhosis, and HCC in the hepatitis B patients were markedly different (P<0.005) compared with the controls. The overall mortality of hepatitis B patients was 4.5-fold higher than the general population. Cox multiple regression analysis showed that old age, severe histological injury, and positive HBeAg were closely related to liver cirrhosis; old age, severe histological injury, and male were major factors leading to death. The independent variable of predicted HCC was not found. CONCLUSION: The long-term outcome of hepatitis B patients is poor and the efficacy of antiviral drugs needs further study.

[Long-term health-related quality of life in chronic hepatitis B patients].

OBJECTIVE: To evaluate their long-term outcome and the efficacy and economic significance of antiviral drugs by investigating the long-term health-related quality of life (HQL) in chronic hepatitis B (CHB) patients. METHODS: The HQL of 101 CHB patients with biopsy-proven 6 to 18 years ago and 105 persons of general population as control was studied with revised SF-36 questionnaire. RESULTS: The HQL in CHB patients was lower than that in general population in physical functioning, role physical, general health, mental health, and specific symptoms (mu > or = 2.10, P<0.05). CONCLUSIONS: The long-term HQL in chronic hepatitis B patients is poor.