Salivary Metabolomic Analysis Reveals Amino Acid Metabolism Shift in SARS-CoV-2 Virus Activity and Post-Infection Condition.

The SARS-CoV-2 virus primarily infects salivary glands suggesting a change in the saliva metabolite profile; this shift may be used as a monitoring instrument during SARS-CoV-2 infection. The present study aims to determine the salivary metabolomic profile of patients with and post-SARS-CoV-19 infection. Patients were without (PCR-), with SARS-CoV-2 (PCR+), or post-SARS-CoV-2 infection. Unstimulated whole saliva was collected, and the 1H spectra were acquired in a 500 MHz Bruker nuclear magnetic resonance spectrometer at 25 °C. They were subjected to multivariate analysis using principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), as well as univariate analysis through t-tests (SPSS 20.0, IL, USA), with a significance level of p < 0.05. A distinction was found when comparing PCR- subjects to those with SARS-CoV-2 infection. When comparing the three groups, the PLS-DA cross-validation presented satisfactory accuracy (ACC = 0.69, R2 = 0.39, Q2 = 0.08). Seventeen metabolites were found in different proportions among the groups. The results suggested the downregulation of major amino acid levels, such as alanine, glutamine, histidine, leucine, lysine, phenylalanine, and proline in the PCR+ group compared to the PCR- ones. In addition, acetate, valerate, and capronic acid were higher in PCR- patients than in PCR+. Sucrose and butyrate were higher in post-SARS-CoV-2 infection compared to PCR-. In general, a reduction in amino acids was observed in subjects with and post-SARS-CoV-2 disease. The salivary metabolomic strategy NMR-based was able to differentiate between non-infected individuals and those with acute and post-SARS-CoV-19 infection.

SARS-COV-2 detection in saliva and nasopharyngeal swabs using RT-PCR was similar.

The World Health Organization has declared the widespread spread of SARS-CoV-2 and its associated disease (COVID-19) a public health emergency. The standard gold test for detecting the virus is the RT-PCR, performed from nasopharyngeal swab (NPS) samples. However, this test may be uncomfortable for the patient and requires specific training and attire from the health professional responsible for collecting the sample. Therefore, the search for alternative ways to collect samples that may be used in the diagnosis of COVID-19 is relevant. This study aimed to compare the results obtained from NPS and saliva samples. NPS and saliva samples were collected from 189 symptomatic outpatients suspected of COVID-19, who came to Piquet Carneiro Polyclinic. RNA extraction was performed using the Bio-Gene DNA/RNA Viral Extraction kit (Bioclin®). Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) reactions used the Molecular SARS-CoV-2 (E / RP) kit (Bio-Manguinhos). The results indicated that 142 showed a non-detectable result (ND), while 47 showed a detectable result (D). Among the 142 "ND", 137 (94.4%) saliva samples obtained the same result, while 5 samples (3.4%) were "D". Among the 47 "D" swab samples, 35 (74.4%) showed the same result in the saliva samples. The sensitivity of the saliva test was 0.74 and the specificity was 0.97. The positive predictive value was 0.88 while the negative predictive value was 0.92. The results showed that detection of Sars-CoV-2 using saliva samples showed high sensitivity and specificity compared to nasopharyngeal swabs.

SARS-COV-2 detection in saliva and nasopharyngeal swabs using RT-PCR was similar

Abstract The World Health Organization has declared the widespread spread of SARS-CoV-2 and its associated disease (COVID-19) a public health emergency. The standard gold test for detecting the virus is the RT-PCR, performed from nasopharyngeal swab (NPS) samples. However, this test may be uncomfortable for the patient and requires specific training and attire from the health professional responsible for collecting the sample. Therefore, the search for alternative ways to collect samples that may be used in the diagnosis of COVID-19 is relevant. This study aimed to compare the results obtained from NPS and saliva samples. NPS and saliva samples were collected from 189 symptomatic outpatients suspected of COVID-19, who came to Piquet Carneiro Polyclinic. RNA extraction was performed using the Bio-Gene DNA/RNA Viral Extraction kit (Bioclin®). Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) reactions used the Molecular SARS-CoV-2 (E / RP) kit (Bio-Manguinhos). The results indicated that 142 showed a non-detectable result (ND), while 47 showed a detectable result (D). Among the 142 "ND", 137 (94.4%) saliva samples obtained the same result, while 5 samples (3.4%) were "D". Among the 47 "D" swab samples, 35 (74.4%) showed the same result in the saliva samples. The sensitivity of the saliva test was 0.74 and the specificity was 0.97. The positive predictive value was 0.88 while the negative predictive value was 0.92. The results showed that detection of Sars-CoV-2 using saliva samples showed high sensitivity and specificity compared to nasopharyngeal swabs.

Resumo A Organização Mundial da Saúde declarou a disseminação generalizada do SARS-CoV-2 e sua doença associada (COVID-19) uma emergência de saúde pública. O teste padrão ouro para detecção do vírus é o RT-PCR, realizado a partir de amostras de swab nasofaríngeo (NPS). No entanto, esse exame pode ser desconfortável para o paciente e requer treinamento específico e vestimenta do profissional de saúde responsável pela coleta da amostra. Portanto, a busca por formas alternativas de coleta de amostras que possam ser utilizadas no diagnóstico de COVID-19 é relevante. O objetivo deste estudo foi comparar os resultados obtidos em amostras de NPS e saliva. Amostras de NPS e saliva foram coletadas de 189 pacientes ambulatoriais sintomáticos com suspeita de COVID-19, que procuraram a Policlínica Piquet Carneiro. A extração de RNA foi realizada com o kit Bio-Gene DNA / RNA Viral Extraction (Bioclin®) e as reações em tempo real da reação em cadeia da polimerase-transcriptase reversa (RT-PCR) usaram o kit Molecular SARS-CoV-2 (E / RP) (Bio-Manguinhos). Os resultados indicaram que 142 apresentaram resultado não detectável (ND), enquanto 47 apresentaram resultado detectável (D). Entre os 142 "ND", 137 (94,4%) amostras de saliva obtiveram o mesmo resultado, enquanto 5 amostras (3,4%) foram "D". Dentre as 47 amostras de swab "D", 35 (74,4%) apresentaram o mesmo resultado nas amostras de saliva. A sensibilidade do teste de saliva foi de 0,74 e a especificidade foi de 0,97. O valor preditivo positivo foi de 0,88, enquanto o valor preditivo negativo foi de 0,92. Os resultados mostraram que a detecção de Sars-CoV-2 em amostras de saliva apresentou alta sensibilidade e especificidade quando comparada com swabs nasofaríngeos.

Reducing the viral load of SARS-CoV-2 in the saliva of patients with COVID-19.

OBJECTIVE: To evaluate the reduction in the salivary viral load using oral antiseptic mouthwashes in patients testing positive for COVID-19. METHODS: Sixty-three individuals were recruited after testing positive for COVID-19 by real-time RT-PCR assay and divided into 5 groups. Group 1 received sterile water, group 2 received 1.5% hydrogen peroxide solution (HP), group 3 received 0.12% chlorhexidine (CHX), group 4 received 0.1% sodium hypochlorite solution (NaClO), and group 5 received sequential rinses using CHX and HP. After collecting the initial saliva sample, individuals were asked to use the designated mouthwash for 1 min. Additional saliva samples were collected immediately after rinsing, 15, and 30 min after rinsing. Real-time RT-PCR assays for RNA detection of SARS-CoV-2 were performed on the saliva samples. RESULTS: There were no significant differences among the experimental groups and the control group in any period. Compared to the baseline values, there was a significant reduction in the number of copies of SARS-CoV-2 after 30 min in group 2 and immediately after the initial mouthwash in group 4. CONCLUSIONS: No experimental group demonstrated a significant reduction in the viral load compared to the control group.

Morphological alterations in tongue epithelial cells infected by SARS-CoV-2: A case-control study.

OBJECTIVE: The aim of the present case-control study was to evaluate the morphological aspects of the epithelial cells from the dorsum of the tongue and the expression of the SARS-CoV-2 Spike protein in these cells, in patients with and without COVID-19 infection. METHODS: 24 individuals with at least one symptom of COVID-19 were recruited among inpatients from Hospital Universitário Pedro Ernesto (Rio de Janeiro, Brazil). 14 patients who tested positive for COVID-19 by RT-PCR were included in the case group, and 10 patients who tested negative were included in the control group. Cytological smears from the dorsum of the tongue were obtained from all patients and analyzed using immunohistochemistry directed against SARS-CoV-2-Spike protein. Morphological changes in epithelial cells were analyzed using light microscopy. RESULTS: Immunohistochemistry showed that 71% of the COVID-19 patients presented epithelial cells positive for the presence of the SARS-CoV-2 Spike protein, and all cells coming from patients in the control group were negative. Cytological analysis showed significant differences when comparing epithelial cells from COVID-19-positive and COVID-19-negative patients. CONCLUSION: COVID-19 may generate dimensional changes in tongue epithelial cells; however, further studies are necessary to understand how this happens.