3.2 Laboratory examination
In
the early stage of the COVID-19, white blood cell count is normal or
decreased, with decreased lymphocyte count. Some patients may present
elevated levels of liver enzymes, lactate dehydrogenase, muscle enzymes
and myoglobin.
The
level of troponin may be increased in critically ill patients. Severe
cases showed
high
level of D-dimer and progressively decreased blood lymphocytes
count(Jin et al., 2020).
The
critical patients often have elevated
level
of inflammatory factors such as IL2, IL7, IL10, GSCF, IP10, MCP1, MIP1a
and TNF-α (Chaolin et al., 2020).
Based upon the evidence from clinical research, the
SARS-CoV-2
nucleic acids can be detected in nasopharyngeal swabs, sputum, lower
respiratory tract secretions using reverse transcription-polymerase
chain reaction (RT-PCR) method(Rothan &
Byrareddy, 2020). Some scholar reported that both
IgM
and IgG titres were markedly increased in nearly all patients, which was
normally considered as a transition from earlier to later period of
infection(Zhang et al., 2020). Therefore,
they developed IgM and IgG detection methods using a cross-reactive
nucleocapsid protein(NP) from another SARSr-CoV Rp3, which is 92%
identical to 2019-nCoV NP.