Ankara Yıldırım Beyazıt University School of Medicine, Department of Chest Diseases, Postal code: 06800

Ankara, Turkey. Phone: +90 0312 552 60 00

Thorax Computed Tomography (CT) led to the diagnosis of COVID-19 pneumonia globally during the pandemic process with a higher sensitivity than laboratory tests.

In our chest illnesses clinic during the pandemic, 224 COVID-19 Pneumonia cases were monitored. Thorax CTs were conducted throughout the pandemic in accordance with recommendations from the World Health Organization, European Radiology Association, and health ministry. A radiologist and an expert in chest diseases analysed and reported on the subjects' thorax CT scans. We gathered cases with the uncommon COVID-19 finding of a centracinar nodule.

The demographic information, symptoms, physical exam results, rt-PCR test results, posteroanterior chest x-ray results, and Thorax CT results of the cases followed in our clinic were documented. 224 cases were monitored over a 3-month period in the clinic for chest disorders. In 11 patients, the sentriacinar nodule pattern was visible on thorax CT.

TheSince the start of 2020, the viral infection that causes COVID-19 (corona virus disease 19) has swiftly spread over the world, impacting most of the European Union's member states in March 2020, with Italy, Spain, France, and Turkey currently suffering the most severe effects [1]. Several research documenting the computed tomography (CT) features and radiological pattern of Corona Disease 2019 have been published in recent months (COVID-19). We evaluated and reported many patterns in patients with the COV-D-19 Pneumonia following a thorough literature search. On the meta-analysis of CT characteristics of COV-D pneumonia patients, groundglass opacities (GGO), consolidation, or both were present in 78% of patients with real-time polymerase chain reaction (RT-PCR) confirmed COVID-19 infections.

As these initial lesions progressed, septal thickening, widespread lesions, consolidations, and air bronchograms were seen in the later stages. These lesions were finally entirely healing, whether there were any fibrotic strips left over or not. Additionally discovered were lymphadenopathy, pleural effusion, and unusual pattern pulmonary vascular pathology. There was an association between and a poor clinical prognosis [2].Nine COVID-19 infected individuals who had undergone chest radiography and CT scans were collected by a Korean researcher. They appeared as areas of consolidation (5%), pure GGO lesions (35%), lesions with a crazy-paving look (10%), and mixed GGO and consolidative lesions (50%).

The bronchovascular bundles were where the nodular lesions were mostly found (59% vs. 28%; p = 0.006), and they tended to present as pure GGO lesions (57% vs. 35%; p = 0.069). [3]. In a different study, 149 patients from a hospital in China were included. By using computed CT, diffuse centriacinar nodules were seen in three patients who had pneumonia [4]. Therefore, the purpose of this case series was to characterise the uncommon imaging symptom of centriacinar nodule in patients with pneumonia thought to be caused by COV-D-19. By using computed tomography, we were able to detect pneumonia in eleven individuals who had diffuse centriacinar nodules.

224 patients in our department of pulmonary were admitted to the hospital. According to the American Thoracic Society and the Infectious Diseases Society of America's 2020 guidelines, pneumonia was identified [5]. Two skilled radiologists and a chest physician reviewed and assessed all imaging characteristics. The CT characteristics included reticular pattern, subpleural linear opacity, bronchial dilatation, cystic change, consolidation, mixed GGO, air bronchogram, nodule, tree-in-bud sign, and ground-glass opacities (GGO).

According to the rules of the Fleischner Society [6], each term was defined. Eleven individuals with COV-D-19 pneumonitis had thorax computed tomography scans that identified ceriacinar nodules.

A 40-year-old man was brought into the emergency room complaining of chills that had been bothering him for one day. Although the patient's posteroanterior chest radiograph in the emergency room did not show anything abnormal, thorax computed tomography results showed centriacinar nodules in the upper lobe posteriorly accompanied by air bronchograms, which were findings consistent with pandemic viral pneumonia in the left lobe (Figure 1). COVID-19 preliminary diagnostic With clinical and test evidence suggesting pneumonia, the patient was admitted to the hospital. Coronavirus detected in a nasopharyngeal swab using real-time PCR. Her résumé and family history lacked this detail.

The patient identified himself as a 40-year-old pack-a-day smoker. Physical examination revealed no abnormal findings.

The following laboratory results were found: white blood cell count of 10.500 per L (80.9% neutrophils, 11.8% lymphocytes, and 5.3% monocytes), haemoglobin 15.3 g.dL-1, thrombocytosis (653.000 per L), increased serum inflammatory markers (erythrocyte sedimentation rate 64 mmh1, C-reactive protein 186 g.L-1, procalcitonin 0.20 mikrog.L-1 Coagulation was slightly increased and renal function was within the normal range (serum d-dimer value: 1.16 mg.dL).

Azithromycin, ceftriaxone, and plaquenil were used to treat the patient. On room air, oxygen saturation as measured by pulse oximetry was 97%. The patients' QT prolongation was monitored by the doctors.

A 48-year-old male patient arrived complaining of a sore throat, myalgia, and shortness of breath that had been going on for a week. The patient also complained of diarrhoea for two days before going to the emergency room. In both lower zones of both lungs, the thorax CT scan showed a micronodular pattern (centriacinar nodules) with poor attenuation. The patient was admitted to the hospital with a preliminary COVID-19 pneumonia diagnosis. The patient admitted to smoking for 20 years, every day. The assessment of the patient revealed a history of HT.

Treatment with antibacterial and antiviral medications began. No new issue arose during the follow-up. The patient received advice before being released.

The emergency room received a referral for a male patient, age 41, who had a positive COVID-19 test and was complaining of weakness and extensive myalgia. Due to the presence of poor attenuation centriacinar nodules, the patient who had thorax computed tomography at the emergency room was hospitalised and given the diagnosis of COVID-19 Pneumonia. The COVID-19 PCR test yielded positive results. He underwent five days of antiviral therapy. On the sixth day following therapy, the second COVID-PCR sent was unfavourable.

Seven days after being admitted, the patient was stable.

A male, age 49, was working with welding. He submitted an application to the emergency room after developing chills and a fever a day earlier. The patient, who had no prior contacts, applied to the emergency room and complained of having lost his or her sense of smell, sore throat, cough, and strength. He was admitted to the hospital due to thorax CT scan results that were compatible with COVID-19. The patient's background and family history lacked any relevant information. He used to light up a few times a day. After receiving antiviral medication, the patient made a partial recovery and was released from the hospital on the sixth day.

25 days ago, a 63-year-old male patient reported having a fever, a headache, and weakness. Shortness of breath and a cough started after one or two days of complaints. The patient sought treatment at the emergency room after 15 days of no improvement in their concerns. Following more noticeable bilateral centriacinar lumps on the right, a thorax CT revealed the patient with COVID-19 Pneumonia (Figure 2).

Her résumé and family history didn't mention it. The patient had been smoke-free for 20 years after smoking a pack of cigarettes every day for 10 years. Her routine biochemistry showed substantial d-dimer rise and lymphopenia. Antiviral therapy was used to treat the patient. The patient's problems subsided, and she was discharged.

After three family members tested positive for COVID, a 42-year-old man was seen at the emergency room. Additional than a temperature and the malaise that had started the day before, the patient had no other complaints. Coronary artery disease was diagnosed concurrently. The patient, who smoked for 20 years at one penny per day, stopped eight months ago. A similar look was found in the patient's CT scan of the thorax. Two COVID-PCR tests that were sent on the first and sixth days following treatment returned positive results. The patient was released after the two COVID-PCR tests that were sent on the 10th and 12th days were found to be negative.

A 34-year-old man who has not been ill for two days is admitted to the emergency room complaining of coughing and shortness of breath. Centrilobular emphysema and diffuse centriacinar nodule were visible on the patient's CT scan (figure 3). With a COVID-19 diagnosis, the patient is admitted to the hospital. The patient had a 20-year history of smoking two packs every day. The results of two PCR testing were negative. The patient was released after receiving treatment for his or her symptoms.

The patient who underwent follow-up and was diagnosed with COPD, OSAS, and CAD had comparable thoracic CT results (Figure 4). Results of the COVID PCR tests were negative. The patient had been smoke-free for ten years after smoking for twenty years and two packs per day. The patient coughed up sputum and had breathlessness. After receiving relief from the treatment, the patient was released with advice.

Similar findings were found in a 38-year-old male patient who was hospitalised after being monitored for bronchiectasis. He experienced a 39 degree temperature, acute myalgia, and weakness. The following laboratory results were found: white blood cell count of 5290/L (82% neutrophils, 12% lymphocytes, and 4.3% monocytes), haemoglobin 13/L, thrombocytosis (157,000/L), increased serum inflammatory markers (erythrocyte sedimentation rate 53 mm.h.1, C-reactive protein 79/L, procalcitonin 0.18 mikrog.L), serum iron and ferritin arrangement of chronic disease (serum Blood clotting was slightly elevated and renal function was within the normal range (0.58 mg.dL-1 fibrinogen 5.54 g-L-1).After receiving treatment with favipravir, the patient's complaints got worse and his test indicators got worse. Clear clinical and laboratory results were obtained after the treatment. The patient was discharged with suggestions after the first two PCR tests were positive and the third and fourth tests were negative.

A 34-year-old male patient with no concomitant conditions and no history of smoking presented with identical CT findings. Results of the COVID PCR test were negative (Figure 5). Following therapy, the patient was released with suggestions.

According to our knowledge, this report contains the largest single-center case study data of COV-D-19 pneumonia patients who were hospitalised and exhibited a centrifugal nodular pattern. The CT imaging of the 11 individuals who were hospitalised and whose lung parenchym had been shown to have central nodules.

Results of laboratory and reverse-transcription polymerase chain reaction (RT-PCR) tests may be delayed while the diagnosis of COVID-19 Pneumonia is confirmed. By diagnosing and describing COVID-19's pulmonary involvement in certain circumstances, radiologists can aid in the treatment of this disease [6]. Common radiographic findings include ground glass opacity, organising pneumonia, and widespread alveolar injury.Additionally, viral infections frequently exhibit this characteristic.

The study was carried out in China during the time of the COVID-19 outbreak. On chest CT scans, imaging patterns such as multifocal, peripheral, pure, mixed, or consolidation were taken into consideration. Centrilobular nodules were less common in patients with positive PCR results, despite the fact that the air bronchogram reticular pattern was more common in those patients. In 5 of our instances, the COVID-19 PCR test was positive. There was no evidence of lymphadenopathy or pleural effusion. According to previously published investigations [15–20], only one of the patients with COVID-19 had cystic alterations and the tree-in-bud sign. In our pulmonology department, 11 patients with a centriacinar nodular pattern have been studied for two months.

Our case series is presented in terms of the necessity to investigate the case in terms of COVID-19 pneumonia with symptoms and findings in patients with a rare pattern of centriacinar nodule.

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