Higher viral loads in asymptomatic COVID-19 patients might be the invisible part of the iceberg.

PURPOSE: SARS-CoV-2 virus dynamics in different hosts and different samples and their relationship with disease severity have not been clearly revealed. The aim of this study is to evaluate the viral loads of 6 different sample types (nasopharyngeal/oropharyngeal combined, oral cavity, saliva, rectal, urine, and blood) of patients with different ages and clinics, to reveal the relationship between disease course and SARS-CoV-2 viral load, and differences in viral loads of asymptomatic and symptomatic patients. METHODS: Nasopharyngeal/oropharyngeal, oral cavity, saliva, rectal, urine, and blood samples are collected from patients who were hospitalized with diagnosis of COVID-19 on admission. Laboratory analysis were carried out at Public Health Institute of Turkey Virology Reference and Research Laboratory. RESULTS: A total of 360 samples from 60 patients were obtained on admission. Fifteen (25%) of the patients were asymptomatic while 45 (75%) were symptomatic. A significant difference was found between mean ages of asymptomatic vs symptomatic patients (26.4 and 36.4, respectively, p = 0.0248). No PCR positivity were found in blood. Only one asymptomatic patient had positive PCR result for urine sample. Viral loads of asymptomatic patients were found to be significantly higher (p = 0.0141) when compared with symptomatic patients. Viral load had a significant negative trend with increasing age. A significant decrease in viral load was observed with increasing disease severity. CONCLUSION: In conclusion, this study demonstrates that asymptomatic patients have higher SARSCoV-2 viral loads than symptomatic patients and unlike in the few study in the literature, a significant decrease in viral load of nasopharyngeal/oropharyngeal samples was observed with increasing disease severity. Factors associated with poor prognosis are found to be significantly correlated with low viral load.

Diagnostic values of HNP 1-3 and procalcitonin levels in synovial fluid aspirates in the differential diagnosis between septic arthritis and noninfectious arthritis.

INTRODUCTION: Although early diagnosis of septic arthritis may reduce mortality rates, and limit unnecessary surgical interventions, clinical parameters alone are not adequate for making the diagnosis of septic arthritis. Therefore, relevant laboratory parameters are used to enhance diagnostic sensitivity. The aim of our study was to assist in making the diagnosis of septic arthritis, and prevent delays in the diagnosis. For this purpose; we aimed to determine the diagnostic values of human neutrophil peptides 1-3 (HNP 1-3) and procalcitonin (PCT) in synovial fluids of patients with arthritis. By comparing the HNP 1-3 and procalcitonin levels, as well as CRP, in synovial fluid aspirates, we evaluated the significance of these data in the differential diagnosis of septic arthritis from noninfectious arthritis. METHODS: A total of 67 adults consisting of 37 septic arthritis and 30 noninfectious arthritis patients were included in our study. As bioindicators; levels of HNP 1-3, PCT, synovial and serum CRP levels were found to have significant ROC areas in discriminating septic arthritis patients from noninfectious arthritis patients. RESULTS: As a result, synovial fluid HNP 1-3 levels were significantly higher in septic arthritis patients compared to noninfectious arthritis patients (p < 0.001). The sensitivity, specificity, and accuracy of HNP 1-3 levels in the diagnosis of septic and noninfectious arthritis were found as 86%, 87%, and 87%, respectively (AUC of the ROC curve = 0.828). CONCLUSIONS: It was decided that the level of HNP 1-3 in the synovial fluid can be used as an alternative indicator in the diagnosis of septic arthritis.

Role of rapid antibody and ELISA tests in the evaluation of serological response in patients with SARS-CoV-2 PCR positivity.

From 7 to 8 days after the onset of symptoms in COVID-19 infection, the sensitivity of serological tests was found to be higher than that of nucleic acid tests. The aims of this study were to investigate antibody levels in patients with SARS-CoV-2 infection, to examine the relationship between antibody levels and virus load, and to evaluate the performance of 2 different commercial kits. A total of 103 patients with confirmed SARS-CoV-2 infection were included in the study. Antibodies against SARS-CoV-2 in serum samples taken from patients were investigated simultaneously with anti-SARS-CoV-2 IgG and IgA ELISAs (Euroimmun) and COVID-19 (SARS-CoV-2) IgG/IgM (Deep Blue) kits. No positivity was detected with any of the test kits in 18 (17.4%) of the 103 samples. In symptomatic patients, 100% of IgM and IgA tests were found to be positive in the group sampled after 10 days, while 100% of IgG tests were found positive after 20 days. The sensitivity of the Deep Blue COVID-19 IgG antibody kit was calculated as 81.48% and the specificity was 97.96%. While there was no statistically significant difference between the PCR CT and ELISA OD values, a positive correlation was found between the ELISA OD values and the days since the date of symptom initiation. The sensitivity and specificity of the rapid antibody test used in this study were found to be quite high. In conditions where ELISA tests cannot be applied, it is thought that it can give an idea in terms of the presence of antibodies as a simple and fast test. Although ELISA tests are valuable in the diagnosis of COVID-19 during the acute period, they are tests that can be used safely in the diagnosis of previous infections and seroepidemiological studies.