Table 2 CT findings, extra-pulmonary manifestation and characteristic laboratory findings of COVID-19 and its mimics
Disease | CT findings | Extra-pulmonary manifestation | Characteristic Laboratory findings | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Location | GGO | Consolidation | Crazy paving | Nodules | Pleural effusion | Other findings | |||||
(1) COVID-19 | Multi-/(less) Unifocal Bilateral Peripheral Posterior or lower zonal | ++++ | ± (more later in the course) | ++ | (R) (either Tree-in-bud or centrilobular) | (R) | (T) Vascular dilation and traction bronchiectasis (S)Architectural distortion and subpleural bands (R) bronchial wall thickening, mucoid impaction or LNs | Abdominal symptoms Acute necrotizing encephalopathy Myocarditis Acute kidney injury | (- -) Lymphocyte count (++) CRP | ||
(2) Viral pneumonia | (a) Influenza A, B and C | Focal Multifocal Diffuse | ++++ | ++ | ++ (Centrilobular) | ++ | Pseudo-cavitation Pneumatocele LNs ± ARDS | Lymphocytosis or lymphopenia | |||
(b) Coronaviridae (SARS/MERS) | Upper and lower resp. infection Multifocal | ++++ | ++ | (R) | (C) Reticulation (R) Cavitation (R) LNs | ||||||
(c) HPIV | Multifocal | ++ | ++++ (patchy) | + (Centrilobular) | Bronchial wall thickening | ||||||
(d) Human adenovirus | Bilateral Multifocal | +++ | Patchy (lobar/segmental) | ++++ (Centrilobular) | ++++ | ||||||
(e) Herpes viruses | Multifocal segmental Diffuse | ++++ | + | (C) Multiple hemorrhagic | ++++ | (C) fungal pneumonia | Gingivostomatitis, pharyngitis and herpes labialis (HSV) | ||||
(f) Human bocavirus | Diffuse Along bronchovascular bundles | ++++ | ++++ (patchy) | ++++ | |||||||
(g) Rhinovirus | Multifocal | ++ | + | (R) | (R) | ||||||
(h) RSV | Airway centric | ± | ++++ | Bronchial wall thickening | |||||||
(j) Measles | Peribronchial | Nodular/reticulo-nodular infiltrates | +++ | Thick interlobular septae (S) Fibrosis (C) Hilar LNs | Lymphadenopathy gastroenteritis, Encephalitis | ||||||
(3) Atypical Bacterial pneumonia (Mycoplasma P. and Chlamydia P.) | Uni-/Bilateral | + | + | + (Centrilobular/peribronchovascular) | (R) | Thick bronchovascular bundle (R) atelectasis Chlamydia P. reticular or linear opacity, airway dilatation and emphysema | Fatigue, Malaise | Mildly ( +) or normal WBC | |||
(4) Pneumocystis jiroveci pneumonia (PJP) | Central with peripheral sparing (++) in upper lobes | ++++ (extensive in non-HIV) | +++ (in non-HIV patients) | ++ (in advanced cases) | + (solitary/multiple) | (C) pulmonary cysts spontaneous pneumothorax (R) cancer-like mass (S) interstitial fibrosis | Tachypnea, tachycardia and cyanosis | (++) LDH (not specific) | |||
(5) Pulmonary edema cardiogenic/non-cardiogenic (ARDS) | Bilateral Perihilar symmetrical (cardiogenic) | ++++ | +++ in ARDS (heterogeneous, peripherally and dependent) | ++ | +++ in cardiogenic edema | (T) Anteroposterior density gradient Pulmonary cysts lately | Cardiomegaly Cyanosis, dyspnea tachypnea in cardiogenic edema | ||||
(6) Hypersensitivity pneumonitis | Acute: normal or diffuse Subacute: mid/upper lung zone Chronic: peribronchovascular (++) at mid/upper lung zones | +++ | Acute: centrilobular ground-glass nodules Subacute: poorly defined CL nodules | Subacute: air trapping (S) Thin walled cysts Chronic: fibrotic changes (septal thickening, traction bronchiectasis, honey combing) | Cyanosis, fatigue, anorexia and weight loss | Non-specific increased ESR and CRP | |||||
(7) Diffuse alveolar hemorrhage | Diffuse Patchy Lobular Perihilar Gravity-dependent | +++ | +++ | ± | Hemoptysis, anemia, signs of collagen-vascular disease | Thrombocytopenia Coagulopathy | |||||
(8) Pulmonary alveolar proteinosis | Patchy Subpleural sparing Geographic distribution ++in lower lung | +++ (T) | No | No | No LNs | Weight loss | Elevated LDH | ||||
(9) Eosinophilic P. | Bilateral non-segmental areas Middle and upper lobar predominance | + | ++++ (no subpleural spacing) | + | + | (S) lung reticulations and mediastinal LNs | Alveolar and blood eosinophilia ++IgE ++ ESR Peripheral thrombocytosis | ||||
(10) Interstitial lung disease | (A) COP | Multifocal Subpleural Peribronchial distribution | ++++ | ++++ | + | (R) masses with regional architectural distortion and interlobular septal thickening. (T) “atoll sign” | Weight loss, generalized bone aches | ||||
(B) DAD/AIP | Symmetric and bilateral Lower lobe predominance Sparing C/P recesses | ++++ | ++ (in the dependent portions) | + | Later fibrotic phase of DAD Architectural distortion, honeycombing and traction bronchiectasis (similar to UIP) | ||||||
(C) CTD associated P. | Subpleural and basal predominance | (S) extensive | (S) Segmental | (S) | (C) reticular densities, traction bronchiectasis, honey combing and clustered cysts (S) mosaic perfusion, discrete cysts and air trapping | Systemic manifestation according to type of disease | Detected antinuclear antibodies (ANA) and an antibody to ribonucleoprotein (RNP) | ||||