Table 1 Comparison between Amiodarone-induced and COVID-19 pneumonia

Clinical onset

Subacute or chronic (drug accumulation over 6–12 months)

Acute or hyperacute (rapid evolution)

Short breath

Common

Common

Dry cough

Common

Common

Fever

Absent or mild

Moderate or high

Fatigue and Myalgia

Absent or mild

Severe and debilitating

Other symptoms

Bradycardia, thyroid dysfunction, blue-grey skin, etc

Anosmia, conjunctivitis, diarrhea, etc

Lactate dehydrogenase and transaminase elevation

Absent or mild

Moderate or severe

Hypoxia

Absent or mild (P/F ratio > 300 mmHg)

Moderate or severe (P/F ratio ≤ 200–300 mmHg)

ARDS

Rare (after cardiothoracic surgery)

Frequent

Bilateral pneumonia

Common (right and upper lobes)

Common (lower lobes)

Interstitial and alveolar opacities

Common

Common

Consolidations with air bronchograms

Predominant

Frequent

Ground glass opacities

Frequent

Predominant

Multifocal distribution

Fewer segments and lobes involved

Many segments (≅ 6) and lobes (≅ 3) involved (patchy distribution)

Hyperattenuation on CT

Frequent (iodine accumulation)

Absent

Pleural thickening (and effusion)

Frequent

Absent or rare

Pericardial thickening

Frequent

Absent or rare

Lymphoadenopathy

Frequent (moderate and reactive)

Absent or rare (lymph node atrophy)

Response to steroids

Good

Variable

Pulmonary thrombosis

Rare

Frequent

Peripheral leukocytosis

Frequent

Frequent

Peripheral neutrophilia

Frequent

Common

Peripheral eosinophilia

Common

Absent or rare

Peripheral lymphopenia

Absent

Common

Alveolar hypercellularity

Common

Common

Alveolar neutrophilia

Frequent

Common

Alveolar eosinophilia

Common

Absent or rare

Alveolar lymphocytosis

Common

Absent or variable

Alveolar CD8⁺ T cells

Increased

Decreased or variable

Alveolar foamy macrophages

Common

Absent or variable

RT-PCR on BALF samples

Negative

Positive for SARS-CoV-2 RNA