Skip to main content

Table 2 CT findings, extra-pulmonary manifestation and characteristic laboratory findings of COVID-19 and its mimics

From: Mimickers of novel coronavirus disease 2019 (COVID-19) on chest CT: spectrum of CT and clinical features

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
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
Acute kidney injury
(- -) Lymphocyte count
(++) CRP
(2) Viral pneumonia (a) Influenza A, B and C Focal
 ++++   ++    ++
 ++ Pseudo-cavitation
  Lymphocytosis or lymphopenia
(b) Coronaviridae (SARS/MERS) Upper and lower resp. infection
 ++++   ++    (R) (C) Reticulation
(R) Cavitation
(R) LNs
(c) HPIV Multifocal  ++  ++++ 
  Bronchial wall thickening  
(d) Human adenovirus Bilateral
 +++  Patchy (lobar/segmental)    ++++ 
(e) Herpes viruses Multifocal segmental
 ++++   +    (C) Multiple hemorrhagic  ++++  (C) fungal pneumonia Gingivostomatitis,
pharyngitis and herpes labialis (HSV)
(f) Human bocavirus Diffuse
Along bronchovascular bundles
 ++++   ++++ 
(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,
(3) Atypical Bacterial pneumonia (Mycoplasma P. and Chlamydia P.) Uni-/Bilateral  +   +     + 
(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)
  (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
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
 +++   +++   ±      Hemoptysis, anemia, signs of collagen-vascular disease Thrombocytopenia
(8) Pulmonary alveolar proteinosis Patchy
Subpleural sparing
Geographic distribution
 ++in lower lung
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
 ++ ESR
Peripheral thrombocytosis
(10) Interstitial lung disease (A) COP Multifocal
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)
  (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)
  1. (C): common, (R): rare, (S):some cases, (T): typical