A Severe Acute Respiratory Syndrome Coronavirus 2 detection method based on nasal and nasopharyngeal lavage fluid: A pilot feasibility study

Very High Negative Concordance Rate of RT-PCR for SARS-CoV-2 in Nasopharyngeal Swab and Tracheo-Bronchial Aspirate in Children

Reliable testing methods for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in children are essential to allow normal activities. Diagnosis of SARS-CoV-2 infection is currently based on real-time reverse transcriptase-polymerase chain reaction (RT-PCR) performed on nasopharyngeal (NP) swabs; concerns have been raised regarding NP swab accuracy in children to detect the virus because of potential lack of cooperation of the patients or due to general uncertainties about concordance between high and low respiratory tract specimens in children. The aim of the study (IRB approval: ST/2020/405) is to prospectively compare RT-PCR results on NP and tracheo-bronchial aspirate (TA) in children admitted to the hospital for surgery or admitted to the Pediatric Intensive Care Unit (PICU) of a tertiary children hospital in Milano, Italy, during a peak of COVID-19 infections in the city. A total of 385 patients were enrolled in the study: 364 from surgical theater and 21 from PICU. Two patients (0.5%) tested positive on TA and were negative on NP; both cases occurred in November 2020, during a peak of infection in the city. Specificity of NP swab was.995 (95% CI: 0.980-0.999). Two patients with positive NP swabs tested negative on TA.

CONCLUSION

Our study shows that the specificity of SARS-CoV-2 RT-PCR on TA swab, compared to results of SARS-CoV-2 RT-PCR on NP, was very high for negative cases in our pediatric cohort during a period of high epidemiological pressure.

The Effect of Isotonic Saline Nasal Lavages in Improving Symptoms in SARS-CoV-2 Infection: A Case-Control Study

Background: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) mainly colonizes nasopharynx. In upper airways acute infections, e.g., the common cold, saline nasal irrigations have a significant efficacy in reducing symptoms. The present study aimed to test the efficacy of nasal lavages in upper airways symptoms of Coronavirus Disease 2019 (COVID-19).

Methods: A series of consecutive adult subjects who tested positive for SARS-CoV-2 from December 2020 to February 2021 performed daily nasal lavages with saline solution (Lavonase®—Purling, Lugo di Romagna, Italy) for 12 days, starting on the day after the SARS-CoV-2 positive swab. A control group included a historical series of patients who were infected in February-March 2020 and who did not perform lavages. An ad hoc questionnaire regarding symptoms was administered to each subjects at base-line and 10 days after diagnosis (i.e., on the same day of the control swab) in both cases and controls.

Results: A total of 140 subjects were enrolled. 68 participants in the treatment group and 72 in the control group were included. 90% of respondents declared the lavages were simple to use and 70% declared they were satisfied. Symptoms of blocked nose, runny nose, or sneezing decreased by an average of 24.7% after the treatment. Blocked nose and sneezing increased in the same period of time in the control group. Ears and eyes symptoms, anosmia/ageusia symptoms, and infection duration (10.53 days in the treatment group and 10.48 days in the control group) didn't vary significantly among the two groups.

Conclusion: Nasal lavages resulted to significantly decrease nasal symptoms in newly diagnosed SARS-CoV-2 patients. These devices proved to be well-tolerated and easy to be used. Further studies on a larger number of subjects are needed in order to possibly confirm these preliminary results.

Discrepancies of SARS-CoV-2 testing results among patients with total laryngectomy

PURPOSE

Prevention of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is obtained with nasopharyngeal swabs. By the way, there is no consensus regarding sampling in totally laryngectomized subjects (who thus breathe directly by the tracheostomy and, theoretically, may be infected in the trachea). The aim of this study is to evaluate possible differences between swab results in the trachea and in the nasopharynx of this category of patients.

METHODS

A retrospective chart review was performed in April 2021 among patients who previously had been operated on for total laryngectomy and who underwent swabs for SARS-CoV-2 research in 3 health-care centers in Northern-Eastern Italy. Data regarding the site of swabbing (trachea or nasopharynx) were analyzed. A comprehensive review of the literature regarding the same topic was then performed.

RESULTS

A total of 25 totally laryngectomized subjects underwent swabs. Among them, 5 tested positive in the trachea (1) and in the nasopharynx (4). According to the literature review, 4 more subjects tested positive in the trachea (1) and in the nasopharynx (3). Data were overall divergent and no statistically significant correlations emerged between results of the tests performed in the two sites.

CONCLUSION

Due to these discrepancies, both tracheal and nasopharyngeal swabs are recommended in these kinds of patients, to obtain a reliable test and to avoid false negatives.