<unk>  infection should be differentiated from other diseases presenting with cough, fever, shortness of breath and tachypnea.<unk>  infection should be differentiated from other diseases presenting with cough, fever, shortness of breath and tachypnea. The differentials include the following:
Bilateral ground-glass opacities on chest CT
Consolidation
Peripheral ground glass opacity
Possible exposure to infected animals or persons
On CT angiography:
Intra-luminal filling defect
On MRI:
Narrowing of involved vessel
No contrast seen distal to obstruction
Polo-mint sign (partial filling defect surrounded by contrast)
Intra-luminal filling defect
Narrowing of involved vessel
No contrast seen distal to obstruction
Polo-mint sign (partial filling defect surrounded by contrast)
S1Q3T3 pattern representing acute right heart strain
Fleischner sign (enlarged pulmonary artery), Hampton hump, Westermark's sign
Hypercoagulating conditions (Factor V Leiden, thrombophilia, deep vein thrombosis, immobilization, malignancy, pregnancy)
May be associated with metabolic alkalosis and syncope
On CT scan:
Mediastinal lymphadenopathy
Hazy mediastinal fat
On MRI:
Abnormality of cardiac chambers (hypertrophy, dilation)
Delayed enhancement MRI may help characterize the myocardial tissue (fibrosis)
Late enhancement of contrast in conditions such as myocarditis, sarcoidosis, amyloidosis, Anderson-Fabry's disease, Chagas disease)
Mediastinal lymphadenopathy
Hazy mediastinal fat
Abnormality of cardiac chambers (hypertrophy, dilation)
Delayed enhancement MRI may help characterize the myocardial tissue (fibrosis)
Late enhancement of contrast in conditions such as myocarditis, sarcoidosis, amyloidosis, Anderson-Fabry's disease, Chagas disease)
Goldberg's criteria may aid in diagnosis of left ventricular dysfunction: (High specificity)
SV1 or SV2 + RV5 or RV6 ≥3.5 mV
Total QRS amplitude in each of the limb leads ≤0.8 mV
R/S ratio <1 in lead V4
SV1 or SV2 + RV5 or RV6 ≥3.5 mV
Total QRS amplitude in each of the limb leads ≤0.8 mV
R/S ratio <1 in lead V4
Cardiomegaly
Previous myocardial infarction
Hypertension (systemic and pulmonary)
Cardiac arrythmias
Viral infections (myocarditis)
Congenital heart defects
Right heart failure associated with:
Hepatomegaly
Positive hepato-jugular reflex
Increased jugular venous pressure
Peripheral edema
Left heart failure associated with:
Pulmonary edema
Eventual right heart failure
Hepatomegaly
Positive hepato-jugular reflex
Increased jugular venous pressure
Peripheral edema
Pulmonary edema
Eventual right heart failure
On contrast enhanced CT scan:
Enhancement of the pericardium (due to inflammation)
Pericardial effusion
Pericardial calcification
On gadolinium-enhanced fat-saturated T1-weighted MRI:
Pericardial enhancement (due to inflammation)
Pericardial effusion
Enhancement of the pericardium (due to inflammation)
Pericardial effusion
Pericardial calcification
Pericardial enhancement (due to inflammation)
Pericardial effusion
ST elevation
PR depression
Large collection of fluid inside the pericardial sac (pericardial effusion)
Calcification of pericardial sac
Infections:
Viral (Coxsackie virus, Herpes virus, Mumps virus, HIV)
Bacteria (Mycobacterium tuberculosis-common in developing countries)
Fungal (Histoplasmosis)
Idiopathic in a large number of cases
Autoimmune
Uremia
Malignancy
Previous myocardial infarction
Viral (Coxsackie virus, Herpes virus, Mumps virus, HIV)
Bacteria (Mycobacterium tuberculosis-common in developing countries)
Fungal (Histoplasmosis)
May be clinically classified into:
Acute (< 6 weeks)
Sub-acute (6 weeks - 6 months)
Chronic (> 6 months)
Acute (< 6 weeks)
Sub-acute (6 weeks - 6 months)
Chronic (> 6 months)
On CT scan: (not generally indicated)
Consolidation (alveolar/lobar pneumonia)
Peribronchial nodules (bronchopneumonia)
Ground-glass opacity (GGO)
Abscess
Pleural effusion
On MRI:
Not indicated
Consolidation (alveolar/lobar pneumonia)
Peribronchial nodules (bronchopneumonia)
Ground-glass opacity (GGO)
Abscess
Pleural effusion
On MRI:
Prolonged PR interval
Transient T wave inversions
Consolidation (alveolar/lobar pneumonia)
Peribronchial nodules (bronchopneumonia)
Ground-glass opacity (GGO)
Ill-contact
Travelling
Smoking
Diabetic
Recent hospitalization
Chronic obstructive pulmonary disease
Requires sputum stain and culture for diagnosis
Empiric management usually started before culture results
On CT scan: (Takayasu arteritis)
Vessel wall thickening
Luminal narrowing of pulmonary artery
Masses or nodules (ANCA-associated granulomatous vasculitis)
On MRI:
Vessel wall thickening
Luminal narrowing of pulmonary artery
Masses or nodules (ANCA-associated granulomatous vasculitis)
Homogeneous, circumferential vessel wall swelling
Right or left bundle-branch block (Churg-Strauss syndrome)
Atrial fibrillation (Churg-Strauss syndrome)
Non-specific ST segment and T wave changes
Nodules
Cavitation
Takayasu arteritis usually found in persons aged 4-60 years with a mean of 30
Giant-cell arteritis usually occurrs in persons aged > 60 years
Churg-Strauss syndrome may present with asthma, sinusitis, transient pulmonary infiltrates and neuropathy alongwith cardiac involvement
Granulomatous vasculitides may present with nephritis and upper airway (nasopharyngeal) destruction
On CT scan:
Chronic bronchitis may show bronchial wall thickening, scarring with bronchovascular irregularity, fibrosis
Emphysema may show alveolar septal destruction and airspace enlargement (Centrilobular- upper lobe, panlobular- lower lobe)
Giant bubbles
On MRI:
Increased diameter of pulmonary arteries
Peripheral pulmonary vasculature attentuation
Loss of retrosternal airspace due to right ventricular enlargement
Hyperpolarized Helium MRI may show progressively poor ventilation and destruction of lung
Chronic bronchitis may show bronchial wall thickening, scarring with bronchovascular irregularity, fibrosis
Emphysema may show alveolar septal destruction and airspace enlargement (Centrilobular- upper lobe, panlobular- lower lobe)
Giant bubbles
Increased diameter of pulmonary arteries
Peripheral pulmonary vasculature attentuation
Loss of retrosternal airspace due to right ventricular enlargement
Hyperpolarized Helium MRI may show progressively poor ventilation and destruction of lung
Multifocal atrial tachycardia (atleast 3 distinct P wave morphologies)
Enlarged lung shadows (emphysema)
Flattening of diaphragm (emphysema)
Smoking
Alpha-1 antitrypsin deficiency
Increased sputum production (chronic bronchitis)
Cough
Alpha 1 antitrypsin deficiency may be associated with hepatomegaly
Life threatening infection with 2019-nCoV, MERS-CoV and SARS-CoV should be differentiated from each other. The following table differentiates infection from these<unk> es:
Huanan seafood market, Wuhan, Hubei China (December 2019)
Betacoronaviridea, subgenus: Sarbecovirus (Lineage B)
ACE1/2
1-14 days
29.8 kB (> 80% nucleotide identity with SARS-CoV)
Human to human transmission through close contact
14380 confirmed cases
17 deaths
Males > females
Mortality rate 2.7%
IL1B, IFNγ, IP10, and MCP1
GCSF, IP10, MCP1, MIP1A, and TNFα (ICU-admitted)
IL4 and IL10
On CT scan:
Bilateral ground-glass opacities
Peripheral localization and subpleural sparing
Bilateral ground-glass opacities
Peripheral localization and subpleural sparing
Saudi Arabia (September 2012)
Betacoronaviridea (Lineage C)
DPP4 (CD26)
2-14 days
29.9 kB
Limited human to human trasnmission
Reservoirs:
Bats
Civets
Camels
Bats
Civets
Camels
2494 confirmed cases
858 deaths
Mortality rate of 34%
IFNγ, TNFα, IL15, and IL17
On CT scan:
Bilateral, subpleural and basilar infiltrates
Ground glass opacities
Organizing pneumonia-like pattern (subpleural and peribroncho-vascular)
Bilateral, subpleural and basilar infiltrates
Ground glass opacities
Organizing pneumonia-like pattern (subpleural and peribroncho-vascular)
Guangdong, Southern China (November 2002)
Betacoronaviridea (Lineage B)
ACE2
2-7 days
29.3 kB
Human to human transmission through close contact
Reservoirs:
Bats
Civets
Camels
Bats
Civets
Camels
8098 cases
774 deaths
Mortality rate of about 10%
IL1B, IL6, IL12, IFNγ, IP10, and MCP1
On CT scan:
Airspace consolidation
Focal or multi-focal opacities
Airspace consolidation
Focal or multi-focal opacities
Coronavirus differential diagnosis
Swine influenza differential diagnosis
Rubella differential diagnosis
COVID-19 differential diagnosis
Tularemia differential diagnosis
Enterovirus 68 differential diagnosis
Babesiosis differential diagnosis
Anthrax differential diagnosis