Abstract
Background: Inlate 2019, a new coronavirus disease was detected in
Wuhan, China and called COVID-19. There are so many unknown factors
about the virus. Iron metabolism is one of the topics have to be
investigated for the development of therapeutic strategies for COVID-19.
The aim of this study is to assess sequential changes in traditional
biochemical iron status indicators during COVID-19 pneumonia.
Methods: A case-control study. Case group was defined as pneumonia with
PCR-confirmed SARS-CoV-2 and the control group consisted of patients
with non-COVID-19 pneumonia. Biomarkers of anemia and iron metabolism,
CRP, procalcitonin were analyzed. Demographic features, CT findings,
SpO2, development of ARDS, ICU admission, duration of hospitalization,
discharge status (event free survival or death) were evaluated.
Results: 205 hospitalized patients with pneumonia were analyzed
retrospectively. COVID-19 group was significantly younger than control
group. 23 of 106 patients had critical COVID-19 infection. Comorbidity
frequency and mortality rate of patients with COVID-19 pneumonia were
significantly higher. Hb, RET-He, iron, TSAT, CRP, PCT and SpO2 were
significantly lower. Hb, RET-He, iron, TSAT levels significantly
correlated to lung aeration loss, hospitalization day and inflamatory
markers in COVID-19 pneumonia.
Conclusion: The patients with COVID-19 pneumonia had iron deficiency
anemia even they were young. Iron deficiency may effect the lung
aeration loss related to paranchimal infiltrations of COVID-19 and
mortality of the patients with COVID-19 pneumonia. Our data indicates
that iron deficiency is associated with longer hospital stays, lower
oxygenation, higher CRP and procalsitonin.
Keywods: COVID-19, pneumonia, iron, hemoglobin, anemia
Introduction Inlate 2019, a new coronavirus with acute respiratory disease was
detected in Wuhan, China and called SARS-COV-2 (Severe Acute Respiratory
Syndrome Coronavirus-2) (1). The name of the disease has been determined
as Coronavirus disease 2019 (COVID-19) by the World Health Organization.
The diagnosis includes the presence of contact, findings compatible with
viral pneumonia in lung imaging, and laboratory findings not specific to
COVID-19 (such as lymphopenia, d-dimer, ferritin elevation, etc.).
Although reverse transcription polymerase chain reaction (RT-PCR) for
SARS-COV-2 is the gold standard in diagnosis, errors in sampling result
in false negativity in the period of the disease.
The most common symptoms are fever, cough, and dyspnea. Pneumonia,
severe acute respiratory tract infection, renal failure, sepsis/septic
shock, ARDS, and multiorgan failure or even death may develop in more
severe cases (2).
Since the life cycle of SARS-COV-2 has not been fully revealed, there
are still unknown points about the disease. Diagnosis, follow-up and
treatment algorithms are tried to be explained.
A study evaluating the biological roles of some proteins of the novel
coronavirus (3) showed the ORF8 and surface glycoprotein could bind to
the porphyrin. The researchers speculated that orf1ab, ORF10, and ORF3a
proteins could coordinate attack the heme on the 1-beta chain of
hemoglobin to dissociate the iron to form the porphyrin. Thus, it has
been claimed that hemoglobin, which can carry oxygen and carbondioxide,
is reduced, lung cells are damaged due to the inadequate exchange of
carbondioxide and oxygen, and groundglass densities appear in lung
imaging due to inflammatory response.
Anaemia screening only based on hemoglobin measurements is inappropriate
and inconclusive in many subjects. Iron deficiency anemia (IDA) is one
of the most common form of anemia. Various biochemical parameters are
used to diagnose IDA, including ferritin, transferin saturation (TSAT),
serum iron, and mean corpuscular volume (MCV). However, measures of
mature erythrocyte indices MCV, mean corpuscular hemoglobin (MCH), and
red blood cell distribution width (RDW) cannot detect early
iron-deficient erythropoiesis due to the slow turnover of erythrocytes
in circulation (4). Cellular iron status can be determined by the method
of measuring the reticulocyte hemoglobin equivalent (RET-He) (5). RET-He
reflects a ‘shortterm’ indication concerning the status of reticulocytes
hemoglobinization (6).
Serum ferritin is an important parameter in determining iron deficiency
anemia. Serum ferritin concentration generally correlates with total
body iron storage. However, despite the presence of iron deficiency in
the course of liver parenchymal disease, chronic inflammatory diseases,
some infections and storage diseases, normal serum ferritin level can be
found, as well as in hypothyroidism, pregnancy and vitamin C deficiency,
it may be low because ferritin synthesis is decreased (7).
Reticulocytes are the youngest erythrocytes released from bone marrow in
to blood. The reticulocyte hemoglobin content (RET-He) indicates the
amount of iron available in the bone marrow for hemoglobin production.
Therefore, RET-He has been proposed as an indicator of iron status
(8).
In this study; we assessed sequential changes in traditional biochemical
iron status indicators during Covid-19 infection.