1. Introduction
Of the recent variants of concern of the SARS-CoV-2 virus, two of them were devastating all around the world: the alpha variant, with a much higher transmissibility than previous ones [
1], and the delta variant, which affected even fully vaccinated persons [
2]. The delta variant generated more negative outcomes than the alpha in the general population and in the pregnant population. We hypothesize that lung involvement, clinical condition deterioration and blood alterations are also more severe in autumn infection, when the delta variant dominated, compared with spring infections, when the alpha variant dominated, in SARS-CoV-2 critical-infected pregnant patients.
Lung involvement can be evaluated primarily by CT or, in facilities without CT or in ICUs (intensive care units), by conventional chest X-rays. The use of mobile radiology installations allows pulmonary examination in patients in the ICU with minimal position change and without needing to disconnect the patient from life-supporting devices.
Mild and moderate cases of COVID-19 may show no abnormality on chest X-rays, while in severe cases, opacities are visible in both lungs—either interstitial and/or alveolar-type opacities. These opacities are situated to the periphery of the lungs, in lower lobes, and have a tendency to unite. With proper therapy, opacities slowly disappear, but sometimes, they involve the majority of the lung area with a catastrophic deterioration of the patient’s condition. Supplemental oxygen may be required and, sometimes, even intubation [
3].
Patient monitoring and assessment can also be performed by chest X-ray. Patients with initial normal chest images may show abnormalities one week after [
4]. Initially, patients show no abnormality or a tiny focal alteration on chest X-rays [
5]; then, in severe cases of COVID-19, the alteration involves more lobes, becomes bilateral, and consolidation or mixed-patterns occur [
6]. Therefore, Brixia score is even more important when successive chest X-ray images are performed, in order to monitor the lung images [
7].
Since lung abnormalities in COVID-19 do not always generate a proportional clinical symptomatology, standardizing was required, in an attempt to precisely correlate lung abnormalities on chest X-rays and clinical parameters. Semiquantitative methods to standardize conventional chest X-ray images have been reported [
8], each of them partly correlated with patient’s clinical condition [
9]. Other scoring methods were required, trying to involve clinical parameters, too.
The reporting of lung alteration on conventional chest X-ray images was so far standardized using Brixia, SARI, RALE and other scores, of which the Brixia score showed the strongest correlation with the clinical condition of the patient [
10]. H Brixia score was the best predictor for negative outcomes in the ICU. Ref. [
11] The higher the Brixia score, the higher the risk of demise [
12].
The Sepsis-3 task force recommends the qSOFA (quick sequential organ failure assessment) score for identifying patients with suspected infection who are at greater risk of poor outcomes. [
13,
14]. Although the qSOFA score initially aimed to evaluate the complication sequence of disease to generate morbidity, not to predict the outcome, there is a close connection between organ failure and the survival of the patient [
15]. The qSOFA score is a very good predictor for COVID-19-generated mortality [
16]. COVID-19 patients intubated in the emergency department had a higher qSOFA score and a greater number of pre-existing comorbidities [
17].
The study was conducted in accordance with the Declaration of Helsinki, and approved by the Research Ethics Committee of the Elena Doamna Obstetrics and Gynecology University Hospital in Iasi (number 4, 2 April 2020).
The aim of the study was to compare the results of chest X-ray examinations, laboratory tests and the results of the qSOFA scale in the group of patients suffering from COVID-19 infection in the spring and the autumn of 2021. We studied the severity of the course of COVID infection in the Brixia scale compared to qSOFA and biochemical results, in order to check our hypothesis that lung involvement, clinical condition deterioration and blood alterations are more severe in autumn infection compared to spring infection in SARS-CoV-2 critical-infected pregnant patients.
2. Materials and Methods
In a prospective study, all pregnant patients admitted at the Elena Doamna Obstetrics and Gynecology Hospital with a critical form of COVID-19 infection between 1 January 2021 and 1 December 2021 were included. Patients who received conventional chest X-rays in another healthcare unit before/during admission in our hospital, where only results were available and not the X-ray images, were excluded from the study. Patients were considered to be at a critical form of COVID-19 when they required admission to the ICU (intensive care unit) due to at least one of the following symptoms: severe dyspnea, oxygen saturation under 95%, extreme fatigue and loss of state of consciousness. All pregnant patients admitted to the hospital were tested by RT-PCR upon admittance, and the positive patients were considered for this study according to the severity of the disease. However, most severe cases of pregnant COVID-19 patients were directed to us from all over the county, because we were a dedicated COVID-19 hospital for obstetrics and gynecology patients; these patients had already taken a positive RT-PCR test and came by ambulance with respiratory support.
Patients underwent conventional chest X-rays with abdomen shielding for fetal protection. A Siemens Polymobil 10 mobile X-ray installation was used. Brixia scores were calculated for every chest image, and the following scores were considered: A score, upon admittance; H and L scores, the highest and lowest scores throughout hospitalization; and E score, the score at the end of hospitalization. For patients who received only one chest examination, the H score was considered. Since we had very few patients in which L score was not the E score or A score, the L Brixia score was eliminated from this study. The Brixia score was calculated by dividing the image of each lung into three zones, from the top of the lung to the base, and each zone was given a number from 0 to 3 as follows: 0—normal image; 1—interstitial opacities; 2—interstitial and alveolar opacities, predominantly interstitial; 3—interstitial and alveolar opacities, predominantly alveolar. The numbers from all quadrants were added, and a final Brixia score ranging from 0 to 18 was obtained [
18].
For each day of A, H and E Brixia score, the qSOFA (quick sepsis-related organ failure assessment) score was also calculated as follows: one point was added for each of the following existing issues: systolic blood pressure of 100 mmHg or below, respiratory rate over 22 breaths per minute and Glasgow coma scale under 15 [
19]. If any of the previous conditions were present at least once during that specific day, it was considered at qSOFA score calculation.
The blood values on those specific A, H, E Brixia score days, or the closest ones to those days, were considered. We studied the differences between the two groups regarding the Brixia and qSOFA scores, and between the blood values on those specific days: A (admittance), H (highest Brixia score) and E (end of hospitalization).
We divided the patients into two groups: the spring group (group 1, n = 11) from January to May 2021, separated by a two-month period free of severe cases from the autumn group (group 2, n = 7) from August to the end of November 2021. This corresponds to the dominance of the alpha variant of SARS-CoV-2 in spring and the delta variant in autumn of 2021 [
20] in Romania. The median age was 32 (27, 37) years old in group 1 and 34 (30, 37) years old in group 2 (
p = 0.55).
Statistical analysis was performed with SPSS version 18 software (SPSS Inc., Chicago, IL, USA). For descriptive measures, we computed the mean, standard deviation, median and quartiles 1 and 3 (because the variables follow a non-normal distribution). To compare the data, the nonparametric Mann–Whitney U test was applied. The standard significance cut-off at p = 0.05 was used to determine our hypothesis conclusion.
4. Discussion
If lung involvement, clinical condition and blood alterations are worse in pregnant patients affected by the delta compared with the alpha variant of the SARS-CoV-2 virus, delta patients should be monitored more carefully and the management of follow-up must be adapted.
The clinical condition of the patient can be evaluated using NEWS, Qsofa, SIRS, CRB 65 and other scores, of which qSOFA correlated the least with clinical outcomes [
22,
23,
24,
25,
26]. We were not interested in the prognosis but in the clinical evaluation on some particular days; therefore, we considered the qSOFA score as the most appropriate to use, because the Brixia and qSOFA scores are the most appropriate methods to describe the severity of COVID-19 [
27].
In these severe cases of pregnant COVID-19 patients, the inflammatory response (C-reactive protein) was several times higher in autumn patients (when the delta variant dominated) upon admission and on the Brixia H day, which probably led to the dramatic decrease in neutrophils during the end days of hospitalization in the autumn patients. Meanwhile, the spring infection (when the alpha variant dominated) only triggered an inflammatory response, which increased at a constant level throughout the hospitalization. This is in accordance with Fisman [
28] and Rangchaikul [
29], who described an increased risk of hospitalization, ICU admission and death due to the delta variant compared with the alpha variant in the general population and in the pregnant population. Furthermore, Eid [
30] and Zayet [
31] found the delta variant more aggressive and dangerous than the previous variants of concern (alpha included).
The white blood cells and neutrophils slightly and constantly increased in the spring group, but not in the autumn group, where they were within normal limits. No increase or decrease in lymphocyte count was observed in these severe-COVID-19 patients. The pregnancy state probably had a modulatory response and stopped the increase in the white-blood-cell count and lymphocyte count. This would be in accordance with Sievers [
32], who reported the antibody response to SARS-CoV-2 infection to be reduced in pregnant women. Our study is in accordance with Areia [
33], who found that the SARS-CoV-2 virus determined a decrease in white-blood-cell count in pregnant women; furthermore, no alteration of C-reactive protein or of lymphocytes was found in all infected patients, not only severe cases. In severe cases of pregnant COVID-19 patients, Lasser [
34] observed a decreased lymphocyte count; our findings did not corroborate this. Vakili [
35] reported leukocytosis and an increased neutrophil ratio in pregnant women, similarly to us. Al-Saadi [
36] reported lymphocytopenia and neutrophilia in severe cases of COVID-19, but not specifically in pregnant women. We found neutrophilia but no lymphocytopenia in severe cases of pregnant women. Our findings of increased white-blood-cell count and neutrophil count are supported by the findings of Moghadam [
37] in severe cases of pregnant SARS-CoV-2-infected women.
Conventional chest X-ray proved to have an excellent sensitivity in diagnosing lung involvement in moderate-to-severe COVID-19 cases [
38], and the Brixia scale proved to be the best method to evaluate conventional X-ray chest images during the COVID-19 pandemics [
10]. Maroldi [
39] correlated the A, L and E Brixia scores with the outcomes of COVID-19 pneumonia patients, which makes sense: the lower the Brixia score, the less the lungs were affected upon admission (A score); at the end of hospitalization (E score); and, of course, at the lowest lung involvement (L score). The less the lungs are involved, the better the outcome. Maroldi [
39] also correlated the increased Brixia H score (the largest and worst lung involvement) with the increased probability of negative outcomes and death of patients, which also makes sense. Henley [
40] and Palsencia-Martinez [
41] also correlated the highest Brixia scores in a modified version and second Brixia score, respectively, with the probability of later need for ventilation or intubation in COVID-19 patients. However, they did not study the clinical state of the patient together with the Brixia scores, nor did they compare alpha with delta patients as we did. Henley [
40] also reported a mean Brixia score upon admittance to the ICU of 9, and the need for ventilation starting with an 11.5 Brixia score. We reported a median Brixia score of 11.3 upon admittance to the ICU in the spring patients, and 8 in the autumn patients, showing that admittance to the ICU was very late in the spring patients, who stayed home as long as they could. Conversely, in autumn, COVID-19 patients went to hospital earlier due to the more intense delta symptoms and perhaps due to the abundant media information advising citizens to consult a physician as soon as they felt symptoms and tested positive for the SARS-CoV-2 antigen. Borghesi [
42] also correlated the Brixia H score with the outcomes in COVID-19 patients, showing that patients with an H score under 8 had a good prognosis. We cannot confirm that, because our median admittance (A) Brixia score was over 11.3 in spring and over 8 in autumn patients; from there, it went higher to the Brixia H (highest) score. Balbi [
43], d’Souza [
44] and Au-Yong [
45] correlated the Brixia A score with outcomes in COVID-19 patients. Setiawati [
46] found that severe cases of COVID-19 pneumonia had a Brixia score over 6, Gatti [
47] over 7 upon admission and Boari [
48] over 8, but the first and last authors did not specify which Brixia score they used: A, H or E. Similarly, Hoang [
49] and Gurtoo [
50] also correlated Brixia score with the outcomes in COVID-19 patients but did not specify which Brixia score they used in calculations—either A, H or E score—or if there was more than one chest X-ray taken of each patient. In another study, Boari [
51] even correlated the Brixia score with the lung involvement at the posthospitalization follow-up. However, none of them correlated Brixia score with a specific variant of concern, alpha or delta, nor did they describe pregnant patients as we did.
We used the qSOFA score to assess the clinical state of patients on every specific Brixia day—A, H and E—and compared the evolution. In spring patients, the qSOFA score was high upon admittance (A day), decreased slowly until the H day, and then decreased significantly toward the end of hospitalization. In autumn patients, the qSOFA score continued to increase from A day to H day, then decreased dramatically to the end (E day). Moreover, the qSOFA score on admittance (A) day was higher in the spring infection compared with the autumn infection, meaning that the patients’ clinical state was worse in spring patients than in autumn patients upon admittance. During hospitalization, clinical status improved quickly in spring patients (qSOFA score decreased) but continued to deteriorate in autumn patients (qSOFA score increased) towards the H day.
As described above, there was no correlation between the Brixia score and the qSOFA (
p = 1) score on each particular day—A, H or E—in either the spring or the autumn group; the Brixia score (radiological evaluation of lung involvement) increased or decreased days later compared to the more reliable qSOFA score, which exactly described the clinical status of the patient that day. However, neither Brixia score nor qSOFA score in one particular day could predict the radiological or clinical evolution of the patient during the next days, in either spring or autumn patients. This is in accordance with Cagino [
52], Heldt [
53] and Alencar [
54], who found no correlation between qSOFA score and outcomes in pregnant or nonpregnant COVID-19 patients. Still, Aashik [
55] found the qSOFA score to predict the mortality of COVID-19 patients, while Vikas [
56] found the Brixia A score and qSOFA score to predict outcomes in severe forms of pregnant COVID-19 patients.
There was no correlation between either Brixia score or qSOFA score on any particular day (A, H or E) and the blood coagulation factors or biochemical blood values (p = 1), in any group. There were no major alterations of the blood cell indices in the two groups, except for the dramatic difference in neutrophils, which was 6.85 in the spring group versus 2.34 (p = 0.007) in the autumn group at the end of hospitalization, suggesting that the autumn infection determined a depletion of neutrophils. In the spring group, APTT was slightly over the limit only on the end day, at the same level with the admission day in the autumn group; APTT continued to increase up to the H day in this second group and then decreased, showing that hypercoagulability induced by the autumn infection required more heparin and/or patients were already on heparin when transferred to the ICU.
Since the viral loading of SARS-CoV-2 variants was the most important in the lungs, and second in the liver [
57], blood liver enzymes’ level increased. Jang [
58] reported that AST elevated to 126 IU/L and LDH elevated to 409 IU/mL in delta variant pneumonia patients; we observed lower AST and higher LDH in our autumn pregnant patients, when delta variant dominated. No comparisons between alpha- and delta-variant-infected pregnant patients regarding coagulation factors, liver enzymes or blood biochemistry have been found so far.
In this study, we demonstrated our hypothesis that severe cases of COVID-19 patients behaved worse in autumn 2021, when the delta variant dominated, compared with the spring patients, when the alpha variant dominated, with regard to lung involvement, coagulation factors and blood enzymes.
Since the delta variant is much more contagious than the alpha variant, even in a fully vaccinated population [
59,
60], the risk of viral outbreak is still present. Knowing the unpredictable evolution of lung involvement, blood components and coagulation factors will help health professionals react quicker, even in severe cases, especially in the vulnerable population of pregnant persons.
The study has several weaknesses. First, the number of critical-form patients included in each group is small, since our COVID-19-dedicated ICU is small, with few beds, even when they doubled during the pandemics. Second, the moment of performing a conventional chest X-ray may be chosen differently in other hospitals and their results may be different. Therefore, larger studies with more numerous participants are required to confirm these results.