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International Journal of Medical Laboratory
Shahid Sadoughi University of Medical Sciences
Fri, Apr 26, 2024
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Volume 8, Issue 1 (February 2021)
IJML 2021, 8(1): 10-16 |
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Mohebbi N, Pakzadkaramad S, Goharimoghadam K, Jafary M, Rajabi P, Nejat A, et al . Clinical and Paraclinical Characteristics of 57 Deceased COVID-19 Patients in Tehran, Iran: A Retrospective Observational Study. IJML 2021; 8 (1) :10-16
URL: http://ijml.ssu.ac.ir/article-1-369-en.html
URL: http://ijml.ssu.ac.ir/article-1-369-en.html
Niayesh Mohebbi 
, Sara Pakzadkaramad , Keyvan Goharimoghadam , Mohammadreza Jafary , Poorya Rajabi , Afsane Nejat , Amir Kasaeian , Mona Talaschian *
, Sara Pakzadkaramad , Keyvan Goharimoghadam , Mohammadreza Jafary , Poorya Rajabi , Afsane Nejat , Amir Kasaeian , Mona Talaschian *
Department of Internal medicine, Shariati Hospital, Tehran University of medical sciences, Tehran, Iran.
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Introduction
In the past two decades, coronaviruses have caused three novel respiratory diseases called Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), and COVID-19. The latter was discovered in Wuhan, China, in December 2019, which gradually spread worldwide. In 2020, it was considered a pandemic by the World Health Organization (WHO) [1, 2]. The principal clinical symptoms of patients infected with COVID-19 are fever and cough [3]. Therefore, the WHO diagnostic criteria include having a fever above 38˚C, cough, and acute respiratory infection. The Centers for Disease Control and Prevention (CDC) also proposes a similar principle without emphasizing having a cough as a clinical symptom [4].
However, this disease is a challenge for healthcare professionals since not all patients follow the same pattern. There is a whole variety of clinical and paraclinical symptoms that are reported in COVID-19 patients. Myalgia, dyspnea, headache, gastrointestinal disturbances, such as diarrhea and sore throat, are reported clinical symptoms. The laboratory findings reported increased C-reactive protein (CRP) levels, D-dimer levels, lactate dehydrogenase, and procalcitonin [3, 5]. Similarly, the clinical outcome of COVID-19 patients also varies from an asymptomatic or mild fever to severe pneumonia, which could result in intensive care unit (ICU) admission and even death [6-8].
The case fatality rate (CFR) of COVID-19 is constantly changing according to reports and calculations, varying from 4 to 7% [9]. However, it should be mentioned that some scientists believe that the current calculations under-estimate the potential threat of COVID-19 in symptomatic patients [10], and even with these low numbers of CFR, COVID-19 has killed more people than SARS and MERS killed combined [11]. Another factor that we should consider is that the reproduction number of the SARS-COV-2 is higher than SARS. Therefore, even with low CFR numbers could be a major threat to human lives [12]. The CFR also varies between different countries. For instance, on March 12th, the highest CFR was recorded in Italy, China, Iran, and the United States of America. On March 23rd, this figure changed to Italy, Spain, France, Iran, and China [13]. Furthermore, as the pandemic has not finished, all these figures could change in the future. Therefore, each country needs to broaden its knowledge in various aspects regarding this disease.
This study aimed to demonstrate some demographic, clinical, and paraclinical features of the deceased patients with COVID-19 in Iran.
Materials and Methods
A retrospective observational study was conducted to observe and investigate clinical and paraclinical risk factors resulting in death in COVID-19 patients. All patients who died at Shariati Hospital for three months (from February 20th to May 20th, 2020) were evaluated. Those diagnosed with COVID-19 and who had a positive reverse transcriptase-polymerase chain reaction (RT-PCR) test result were included in the study. The patients’ data were collected from their clinical record at the hospital, which consisted of demographic data (age, sex, etc.), clinical symptoms (fever, fatigue, dry cough, etc.), medical history (cardiovascular disease, cancer, etc.) history of medications (NSAIDs, corticosteroids, etc.), laboratory data (liver function test, complete blood count, etc.) and imaging. Each patient was identified by a number to keep the patients’ identities confidential. The study was approved by the Tehran University of Medical Sciences’ ethics committee to be implemented at Shariati Hospital, Tehran, Iran.
Statistical analysis
The data were then categorized and imported to IBM SPSS software version 21. All data were analyzed using either Mann-Whitney or Fisher’s test to evaluate any differences between the two genders. The alpha level was set at 0.05.
Results
From February 20th to May 20th, 2020, 148 patients susceptible to COVID-19 died in Shariati Hospital. Fifty-seven of those patients had a positive RT-PCR test result for COVID-19. Therefore, they were included in our observation. Also, a total of 733 COVID-19 patients visited the hospital during that time, indicating that the CFR in this center was about 7.7%. The patients’ demographic data and laboratory test results are demonstrated in Table 1.
The deceased patients had a mean age of 63.86±16.428, and most were males (59.65%). The patients’ clinical symptoms, past medical history, and comorbidities are summarized in table 2. Except for experiencing nausea and vomiting, which was significantly higher in females with a prevalence of 34.78%, there was no statistically significant difference between males and females. The most common symptoms among the patients were dyspnea (64.91%), weakness (61.40%), fever (60.71%), and having ground-glass opacities in the CT scans (85.96%). Comorbidities of hypertension (47.37%) and diabetes (36.84%) were the most common ones. Almost all the patients needed ventilation (96.5%), so mechanical ventilation was employed for most of them (92.45%).
Discussion
According to the published data, patients with COVID-19 experiencing a more severe and progressive form of the disease are older than those who are more stable and have milder symptoms. For instance, the mean age of patients with progressive symptoms in a study in Wuhan, China, was 65, which is similar to the patients in the present study with the mean age of 63. The proportion of males with severe disease was similar to our results (56.9% vs. 59.65%), indicating that men are slightly more vulnerable to the COVID-19, even though the difference is not statistically significant [14]. The most common symptoms in the patients were dyspnea (64.91%), fatigue (61.40%), and fever (60.71%). Two of the most important comorbidities for COVID-19 are hypertension and diabetes [15]. The proportion of patients with hypertension or diabetes who experience severe symptoms is higher than patients with milder symptoms. Our study results showed that 47.37% of the deceased patients had hypertension, and 36.84% had diabetes. Similar results can be seen in the patients’ non-surviving groups in a retrospective cohort study in Wuhan, China, with 48% for hypertension and 31% for diabetes [14].
As for the laboratory test results, the liver function test, including alanine amino-transferase and aspartate amino-transferase, shows a minor increase in patients with severe symptoms, consistent with our results. It should be mentioned that no significant change was observed in the total population of COVID-19 patients [5, 14, 16]. According to the literature, lactic acid dehydrogenase, serum ferritin, D-dimer, and procalcitonin are all associated with death, confirming our findings. The only considerable thing in our results is that patients had much higher Lactic acid dehydrogenase levels than what was reported before in other studies (1214.121 compared to 521 in non-surviving patients) [14].
However, this disease is a challenge for healthcare professionals since not all patients follow the same pattern. There is a whole variety of clinical and paraclinical symptoms that are reported in COVID-19 patients. Myalgia, dyspnea, headache, gastrointestinal disturbances, such as diarrhea and sore throat, are reported clinical symptoms. The laboratory findings reported increased C-reactive protein (CRP) levels, D-dimer levels, lactate dehydrogenase, and procalcitonin [3, 5]. Similarly, the clinical outcome of COVID-19 patients also varies from an asymptomatic or mild fever to severe pneumonia, which could result in intensive care unit (ICU) admission and even death [6-8].
The case fatality rate (CFR) of COVID-19 is constantly changing according to reports and calculations, varying from 4 to 7% [9]. However, it should be mentioned that some scientists believe that the current calculations under-estimate the potential threat of COVID-19 in symptomatic patients [10], and even with these low numbers of CFR, COVID-19 has killed more people than SARS and MERS killed combined [11]. Another factor that we should consider is that the reproduction number of the SARS-COV-2 is higher than SARS. Therefore, even with low CFR numbers could be a major threat to human lives [12]. The CFR also varies between different countries. For instance, on March 12th, the highest CFR was recorded in Italy, China, Iran, and the United States of America. On March 23rd, this figure changed to Italy, Spain, France, Iran, and China [13]. Furthermore, as the pandemic has not finished, all these figures could change in the future. Therefore, each country needs to broaden its knowledge in various aspects regarding this disease.
This study aimed to demonstrate some demographic, clinical, and paraclinical features of the deceased patients with COVID-19 in Iran.
Materials and Methods
A retrospective observational study was conducted to observe and investigate clinical and paraclinical risk factors resulting in death in COVID-19 patients. All patients who died at Shariati Hospital for three months (from February 20th to May 20th, 2020) were evaluated. Those diagnosed with COVID-19 and who had a positive reverse transcriptase-polymerase chain reaction (RT-PCR) test result were included in the study. The patients’ data were collected from their clinical record at the hospital, which consisted of demographic data (age, sex, etc.), clinical symptoms (fever, fatigue, dry cough, etc.), medical history (cardiovascular disease, cancer, etc.) history of medications (NSAIDs, corticosteroids, etc.), laboratory data (liver function test, complete blood count, etc.) and imaging. Each patient was identified by a number to keep the patients’ identities confidential. The study was approved by the Tehran University of Medical Sciences’ ethics committee to be implemented at Shariati Hospital, Tehran, Iran.
Statistical analysis
The data were then categorized and imported to IBM SPSS software version 21. All data were analyzed using either Mann-Whitney or Fisher’s test to evaluate any differences between the two genders. The alpha level was set at 0.05.
Results
From February 20th to May 20th, 2020, 148 patients susceptible to COVID-19 died in Shariati Hospital. Fifty-seven of those patients had a positive RT-PCR test result for COVID-19. Therefore, they were included in our observation. Also, a total of 733 COVID-19 patients visited the hospital during that time, indicating that the CFR in this center was about 7.7%. The patients’ demographic data and laboratory test results are demonstrated in Table 1.
The deceased patients had a mean age of 63.86±16.428, and most were males (59.65%). The patients’ clinical symptoms, past medical history, and comorbidities are summarized in table 2. Except for experiencing nausea and vomiting, which was significantly higher in females with a prevalence of 34.78%, there was no statistically significant difference between males and females. The most common symptoms among the patients were dyspnea (64.91%), weakness (61.40%), fever (60.71%), and having ground-glass opacities in the CT scans (85.96%). Comorbidities of hypertension (47.37%) and diabetes (36.84%) were the most common ones. Almost all the patients needed ventilation (96.5%), so mechanical ventilation was employed for most of them (92.45%).
Discussion
According to the published data, patients with COVID-19 experiencing a more severe and progressive form of the disease are older than those who are more stable and have milder symptoms. For instance, the mean age of patients with progressive symptoms in a study in Wuhan, China, was 65, which is similar to the patients in the present study with the mean age of 63. The proportion of males with severe disease was similar to our results (56.9% vs. 59.65%), indicating that men are slightly more vulnerable to the COVID-19, even though the difference is not statistically significant [14]. The most common symptoms in the patients were dyspnea (64.91%), fatigue (61.40%), and fever (60.71%). Two of the most important comorbidities for COVID-19 are hypertension and diabetes [15]. The proportion of patients with hypertension or diabetes who experience severe symptoms is higher than patients with milder symptoms. Our study results showed that 47.37% of the deceased patients had hypertension, and 36.84% had diabetes. Similar results can be seen in the patients’ non-surviving groups in a retrospective cohort study in Wuhan, China, with 48% for hypertension and 31% for diabetes [14].
As for the laboratory test results, the liver function test, including alanine amino-transferase and aspartate amino-transferase, shows a minor increase in patients with severe symptoms, consistent with our results. It should be mentioned that no significant change was observed in the total population of COVID-19 patients [5, 14, 16]. According to the literature, lactic acid dehydrogenase, serum ferritin, D-dimer, and procalcitonin are all associated with death, confirming our findings. The only considerable thing in our results is that patients had much higher Lactic acid dehydrogenase levels than what was reported before in other studies (1214.121 compared to 521 in non-surviving patients) [14].
Table1. Patients’ demographic and laboratory data
| Female | Male | P-Value | |||
| N | Mean ± SD | N | Mean ± SD | ||
| Age (year) | 23 | 61.522 ± 18.74 | 34 | 65.441 ± 14.747 | 0.6138 |
| BMI (kg/m2) | 21 | 26.563 ± 3.988 | 30 | 25.331 ± 3.319 | 0.2592 |
| Initial pulse rate (pulse/minute) | 22 | 104.045 ± 19.007 | 34 | 99.588 ± 20.172 | 0.2268 |
| Hospitalization time (day) | 16 | 5.188 ± 5.115 | 25 | 7 ± 8.266 | 0.7657 |
| Invasive ventilation (day) | 20 | 3.55 ± 6.901 | 27 | 3.963 ± 6.892 | 0.4601 |
| Non-invasive time to ventilation (day) |
20 | 1.4 ± 4.147 | 27 | 1.148 ± 2.824 | 0.9464 |
| Time to start ventilation (day) | 23 | 3.478 ± 3.703 | 32 | 7.031 ± 9.282 | 0.2106 |
| Time to dependent mv (day) | 23 | 3.348 ± 6.485 | 33 | 5.061 ± 7.734 | 0.3567 |
| Initial respiratory rate (breaths/min) |
23 | 26.13 ± 17.932 | 32 | 22.438 ± 7.687 | 0.6594 |
| Initial systolic Blood Pressure (mmHg) |
23 | 122.304 ± 26.345 | 32 | 116.531 ± 15.56 | 0.2552 |
| Initial diastolic Blood Pressure (mmHg) |
23 | 68.348 ± 13.145 | 33 | 74.242 ± 11.667 | 0.1597 |
| Initial temperature (˚C) | 22 | 37.418 ± 0.972 | 33 | 37.761 ± 1.294 | 0.3935 |
| WBC (per mm3) | 23 | 14650 ± 22320.85 | 32 | 7906.25 ± 5661.838 | 0.4183 |
| Hb (g/dL) | 22 | 10.791 ± 2.832 | 32 | 12.181 ± 3.388 | 0.0940 |
| CRP (mg/L) | 21 | 67.614 ± 34.484 | 30 | 70.023 ± 27.858 | 0.5918 |
| AST (U/L) | 21 | 74.857 ± 55.329 | 30 | 72.767 ± 68.37 | 0.9508 |
| ALT (U/L) | 21 | 46.714 ± 47.123 | 31 | 48.032 ± 41.667 | 0.5262 |
| ALP (U/L) | 22 | 351.909 ± 507.558 | 30 | 244.667 ± 183.591 | 0.4537 |
| Bilirubin T (mg/dL) | 17 | 1.382 ± 1.101 | 27 | 95.383 ± 272.923 | 0.0554 |
| Bilirubin D (mg/dL) | 17 | 0.713 ± 0.793 | 25 | 1.795 ± 4.423 | 0.5716 |
| LDH (U/L) | 12 | 1146 ± 632.781 | 21 | 1253.048 ± 930.555 | 0.9559 |
| D-dimer (mcg/mL) | 4 | 2.625 ± 2.213 | 10 | 2.792 ± 3.298 | 2.213 |
| Ferritin (ng/mL) | 6 | 2552 ± 4273.349 | 10 | 2170.2 ± 3054.047 | 0.7715 |
| Procalcitonin (ng/mL) | 9 | 1.668 ± 2.868 | 14 | 1.106 ± 1.19 | 0.8291 |
Hb= Hemoglobin; CRP= C-Reactive protein; ALT= Alanine aminotransferase; AST= Aspartate aminotransferase; ALP= Alkaline phosphatase; WBC= White blood cells; LDH= Lactic acid dehydrogenase
Table2. Clinical symptoms and past medical history of the patients
| Symptoms | Male, N=34 N (%) |
Female, N=23 N (%) |
P-Value |
| Fever | 22 (64) | 12 (52.17) | 0.405 |
| Fatigue | 18 (52.94) | 17 (73.91) | 0.166 |
| Dyspnea | 23 (67.65) | 14 (60.87) | 0.778 |
| Dry cough | 13 (38.24) | 8 (34.78) | 1.000 |
| Myalgia | 10 (29.41) | 6 (26.09) | 1.000 |
| Chest pain | 4 (11.76) | 0 (0) | 0.140 |
| Sore throat | 1 (2.94) | 0 (0) | 1.000 |
| Nausea vomiting | 3 (8.82) | 8 (34.78) | 0.020 |
| Diarrhea | 0 (0) | 2 (8.70) | 0.159 |
| Anorexia | 3 (8.82) | 3 (13.04) | 0.677 |
| Melena | 1 (2.94) | 2 (8.70) | 0.559 |
| LOC | 2 (5.88) | 3 (13.04) | 0.384 |
| Confusion | 3 (8.82) | 0 (0) | 0.265 |
| Oliguria | 9 (26.47) | 5 (21.74) | 0.762 |
| Lymphadenopathy | 4 (11.76) | 5 (21.74) | 0.461 |
| Crackles | 10 (29.41) | 7 (30.43) | 1.000 |
| Crazy paving | 2 (5.88) | 1 (4.35) | 1.000 |
| Past medical history | |||
| Diabetes | 15 (44.12) | 6 (26.09) | 0.263 |
| CKD | 4 (11.76) | 2 (8.70) | 1.000 |
| Cardiac dysfunction | 8 (23.53) | 4 (17.39) | 0.744 |
| Pulmonary disease | 4 (11.76) | 2 (8.70) | 1.000 |
| Cancer | 5 (14.71) | 7 (30.43) | 0.193 |
| Transplantation | 4 (11.76) | 1 (4.35) | 0.638 |
| HIV | 0 (0) | 0 (0) | - |
| HTN | 13 (38.24) | 14 (60.87) | 0.112 |
| Arrythmia | 2 (5.88) | 3 (13.04) | 0.384 |
| Medications | |||
| Prophylactic Hydroxychloroquine | 1 (2.94) | 1 (4.35) | 1.000 |
| Flu vaccine | 0 (0) | 0 (0) | - |
| Cytotoxic drugs | 5 (14.71) | 3 (13.04) | 1.000 |
| Chemotherapy | 2 (5.88) | 5 (21.74) | 0.106 |
| NSAID | 2 (5.88) | 0 (0) | 0.510 |
| Smoking | 4 (11.76) | 2 (8.70) | 1.000 |
| Oral corticosteroid | 2 (5.88) | 3 (13.04) | 0.384 |
| Inhaled corticosteroid | 1 (2.94) | 1 (4.35) | 1.000 |
| Kaletra® | 27 (79.41) | 16 (69.57) | 0.532 |
| Antibiotics | 33 (97.06) | 21 (91.30) | 0.502 |
| Hydroxychloroquine | 28 (82.35) | 22 (95.65) | 0.223 |
| Imagings | |||
| Consolidation | 16 (47.06) | 10 (43.48) | 1.000 |
| Ground glass | 27 (79.41) | 22 (95.65) | 0.125 |
| Pleural effusion | 10 (29.41) | 6 (26.09) | 1.000 |
| Nodular lesions | 3 (8.82) | 3 (13.04) | 0.677 |
| Patient management | |||
| Mechanical ventilation | 30 (93.75) | 19 (90.48) | 1.000 |
CKD= Chronic kidney disease; HIV= Human immunodeficiency virus; HTN= Hypertension; NSAID= Non-Steroidal anti-inflammatory drug; LOC= Loss of consciousness
The chief imaging features observed in the CT scans were the consolidations (45.61%) and the ground-glass opacities (85.96%), which is consistent with the previous reports [14].
There was no statistically significant difference between the two genders regarding any of the factors discussed in this article except for a higher incidence of nausea and vomiting in female patients. Almost all observations in this study were consistent with previous observations from other centers. One of the discrepancies of our results was that having a fever as a symptom of the disease was less frequent in the deceased patients in Iran (60.71%) than other studies that reported numbers as high as 90% [14, 17].
Conclusion
Most of the deceased COVID-19 patients had ground-glass opacities in their CT scans. Dyspnea, fatigue, and fever were the most frequent symptoms; however, it should be mentioned that “fever” had a lower frequency in our center compared to previous studies. Hypertension and diabetes were the most important comorbidities. There was almost no significant difference between the two genders regarding clinical and paraclinical symptoms. An important limitation of this study was the missing data from the clinical records, and therefore, a prospective cohort study may give us a more complete and detailed set of data about patients with COVID-19.
Conflicts of Interest
There is no conflict of interest to report.
Acknowledgments
This study was funded by the Tehran University of Medical Sciences.
There was no statistically significant difference between the two genders regarding any of the factors discussed in this article except for a higher incidence of nausea and vomiting in female patients. Almost all observations in this study were consistent with previous observations from other centers. One of the discrepancies of our results was that having a fever as a symptom of the disease was less frequent in the deceased patients in Iran (60.71%) than other studies that reported numbers as high as 90% [14, 17].
Conclusion
Most of the deceased COVID-19 patients had ground-glass opacities in their CT scans. Dyspnea, fatigue, and fever were the most frequent symptoms; however, it should be mentioned that “fever” had a lower frequency in our center compared to previous studies. Hypertension and diabetes were the most important comorbidities. There was almost no significant difference between the two genders regarding clinical and paraclinical symptoms. An important limitation of this study was the missing data from the clinical records, and therefore, a prospective cohort study may give us a more complete and detailed set of data about patients with COVID-19.
Conflicts of Interest
There is no conflict of interest to report.
Acknowledgments
This study was funded by the Tehran University of Medical Sciences.
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Received: 2020/07/17 | Accepted: 2020/09/23 | Published: 2021/03/4
Received: 2020/07/17 | Accepted: 2020/09/23 | Published: 2021/03/4
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