H1N1 influenza
COVID-19
versus H1N1: challenges in radiological diagnosis—comparative study on 130 patients using chest HRCT. Mixed parenchymal/alveolar and airway abnormalities seen with H1N1: 47-year-old male H1N1 patient. a Axial HRCT chest lung window with “MIP” reconstruction demonstrating tree in bud nodules (blue arrows) and small ground-glass opacities. b Axial HRCT lung window showing mild bronchiectatic changes with “signet ring sign” (red arrows), patchy areas of mild air trapping (yellow arrows), and tiny few right lower sub-pleural tree in bud nodules (green arrow)
COVID-19
versus H1N1: challenges in radiological diagnosis—comparative study on 130 patients using chest HRCT. Mixed parenchymal/alveolar and airway abnormalities seen with H1N1: 37-year-old male H1N1 patient. a Axial HRCT chest lung window showing right sided mild alveolar ground glass nodular opacities (yellow square). b Axial HRCT lung window showing left lingular zone and to lesser extent right middle lobar air trapping with bronchiectatic changes (blue arrow) and mucous plugging (red arrow)
COVID-19
versus H1N1: challenges in radiological diagnosis—comparative study on 130 patients using chest HRCT. Pure parenchymal/alveolar pattern which cannot differentiate COVID19 from H1N1. a, b 44-year-old-male COVID-19 patient with axial HRCT chest lung window showing bilateral upper and lower lobar peripheral sub-pleural pure ground glass opacities. They shows smooth septal thickening on the right side “Crazy paving pattern” (red arrows). c, d 54-year-old male H1N1 patient with axial HRCT chest lung window showing bilateral upper and lower lobar mainly peripheral and sub-pleural dense ground glass patches
COVID-19
versus H1N1: challenges in radiological diagnosis—comparative study on 130 patients using chest HRCT. Severe cases complicated by diffuse alveolar damage (DAD), which cannot differentiate COVID19 from H1N1. a, b 52-year-old male COVID-19 patient with axial HRCT chest lung window showing bilateral ground glass opacities, more extensive and dense on the left side showing “crazy paving pattern” and mixed with mild air filled cystic changes denoting “early DAD.” c, d 58-year-old male H1N1 patient with axial and coronal HRCT chest lung window showing bilateral, predominantly upper lobar, ground glass opacity showing “crazy paving pattern” and mixed with air dilled cystic changes denoting “DAD”
H1N1
influenza • Influenza A (H1N1) pneumonia - Ganzer Fall bei Radiopaedia
H1N1
influenza • Swine flu (H1N1 influenza) - complete white out - Ganzer Fall bei Radiopaedia
Ground-glass
opacification • H1N1 pneumonia - Ganzer Fall bei Radiopaedia
H1N1
influenza • Influenza A pneumonia - Ganzer Fall bei Radiopaedia
H1N1 influenza is a strain of influenza that notably resulted in a pandemic in 2009. It was referred to colloquially as 'swine flu' due to the origin of the virus, but it was also named H1N1/09 virus. A specific but different strain of H1N1 (called H1N1 influenza A) was the cause of the Spanish flu, one of the worst global pandemics in recorded human history . This article refers to the disease resulting from the H1N1/09 virus.
Clinical presentation
There can be a wide spectrum of clinical syndromes ranging from being asymptomatic to fulminant viral pneumonia, respiratory failure and death.
Pathology
It is caused by a type of influenza A virus of swine origin.
Radiographic features
Plain radiograph
It can have a variable presentation and a number of features have been described : In the majority of cases the chest radiograph can be normal.
- initial chest radiographs usually show central or peripheral pulmonary ground-glass opacities (GGO) and consolidations that have a patchy or nodular appearance
- multizonal and bilateral peripheral opacities are associated with adverse prognosis
- it should be stressed that a normal radiograph cannot exclude a poor outcome
CT
Described imaging spectrum is broad, with each individual feature being non-specific on its own :
- ground-glass attenuation: ~70% region (most common)
- bronchial wall thickening: ~45% (second most common)
- confluent consolidation: ~30%
- patients are thought to have worse clinical progression
- typically tends to be peripheral consolidation involving the lower lobes
- can also frequently involve all lobes
- pleural effusion: ~30%
- atelectatic changes: ~25%
- pneumothorax/pneumomediastinum
See also
Siehe auch:
und weiter:
Assoziationen und Differentialdiagnosen zu H1N1-Influenza Pneumonie:
