A Study of the relation of COVID-19 infection and its severity to upper and lower airway nitric oxide, upper airway viral load and lung function.
Materials and methods: Prospective cohort of 40 COVID-19, severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2), positive patients from Tampere university hospital region are
recruited to the study. Forty COVID-19 negative patients with similar symptoms act as a
control group.
All subjects are screened for other respiratory viruses with reverse transcriptase polymerase
chain reaction (RT-PCR)-multiplex tests. Viral loads of SARS-CoV-2 from anterior nasal
cavity, nasopharynx, throat and saliva are evaluated by RT-PCR cycle treshold (Ct) value and
antigen testing (RLU value).
During the first visit NEWS (National Early Warning Score), recorded pulmonary auscultation
(Thinklabs One, Thinklabs Medical LLC), impulse oscillometry (Tremoflo, THORASYS Thoracic
Medical Systems Inc), FeNO (fractional exhaled nitric oxide) and FnNO (fractional nasal
nitric oxide) (NIOX VERO®,Circassia) are conducted. All aforementioned and a spirometry are
measured again after 2 months.
Aims: To evaluate the relation of COVID-19 infection and its severity to upper and lower
airway nitric oxide, viral load and lung function. To compare the capability of RT-PCR in
detecting SARS-CoV-2 RNA from saliva, anterior nasal swab samples and oropharyngeal swap
samples vs. the golden standard of nasopharyngeal swab samples. To compare the results of
RT-PCR and antigen test in detecting SARS-CoV-2 from nasal and pharyngeal sample sites.
Inclusion Criteria:
- capable of breathing through nose, no need of supplemental oxygen, symptom onset
within 10 days, positive SARS-CoV-2 test in Fimlab and capable of performing all
required tests
Exclusion Criteria:
- need of supplemental oxygen, pregnancy, lactation, incapability of performing the
tests for any reason, use of organic nitrate medication
Tampere University Hospital
Tampere, Finland
Lauri Lehtimäki, Professor, Principal Investigator
Tampere University Hospital