Legionellosis differential diagnosis

Legionellosis Microchapters
Home
Patient Information
Overview
Historical Perspective
Classification
Pathophysiology
Causes
Differentiating Legionellosis from other Diseases
Epidemiology and Demographics
Risk Factors
Natural History, Complications and Prognosis
Diagnosis
History and Symptoms
Physical Examination
Laboratory Findings
Chest X Ray
CT
Other Diagnostic Studies
Treatment
Medical Therapy
Prevention
Cost-Effectiveness of Therapy
Future or Investigational Therapies
Case Studies
Case #1
Legionellosis differential diagnosis On the Web
Most recent articles
Most cited articles
Review articles
CME Programs
Powerpoint slides
Images
American Roentgen Ray Society Images of Legionellosis differential diagnosis All Images X-rays Echo & Ultrasound CT Images MRI
Ongoing Trials at Clinical Trials.gov
US National Guidelines Clearinghouse
NICE Guidance
FDA on Legionellosis differential diagnosis
CDC on Legionellosis differential diagnosis
Legionellosis differential diagnosis in the news
Blogs on Legionellosis differential diagnosis
Directions to Hospitals Treating Legionellosis
Risk calculators and risk factors for Legionellosis differential diagnosis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Legionellosis must be differentiated from other causes of fever, dyspnea, cough, and sputum production, such as bacterial pneumonia, viral pneumonia, and other causes of atypical pneumonia.

Differential Diagnosis

Legionellosis must be differentiated from other causes of fever, dyspnea, cough, and sputum production, such as bacterial pneumonia, viral pneumonia, and other causes of atypical pneumonia.

Disease	Clinical manifestation	Lab findings	Imaging findings	Chest X-ray
Legionellosis	Adult respiratory distress syndrome Bronchial breath sounds Dry cough High grade fever Progressive dyspnea diarrhea nausea, and vomiting	Legionella urinary antigen positive Leukocytosis with relative lymphopenia Hyponatremia Hypophosphatemia	Alveolar consolidation on chest radiograph Lobar consolidation on chest radiograph
Q fever	Abrupt onset of fever, myalgia, headache, and other constitutional symptoms Dry cough Dyspnea Pleuritic chest pain	Antibody detection using indirect immunofluorescence (IIF) PCR C. burnetii cultivated on special media such as embryonated eggs or cell culture A two-to-three fold increase in AST and ALT		Q fever pneumonia - Case courtesy of Royal Melbourne Hospital Respiratory, Radiopaedia.org, rID 21993
Mycoplasma pneumonia	Dry cough Pleuritic chest pain Bronchial breath sounds Inflamed, opaque, hypomobile tympanic membrane	Lymphocytosis Cold agglutinins positive Positive Coombs test Leukocytosis Thrombocytosis	Alveolar consolidation on chest radiograph Interstitial infiltrate on chest radiograph Lobar consolidation on chest radiograph	Mycoplasma pneumonia - Case courtesy of Dr Alborz Jahangiri, Radiopaedia.org, rID 45781
Chlamydia pneumonia	No specific clinical features of chlamydia pneumonia. Gradual symptoms Associated with upper respiratory tract symptoms Associated with extrapulmonary maifestations such as: Meningitis Guillain-Barre syndrome	Normal WBC count Positive antichlamydial antibody		Chlamydia-pneumonia - Case courtesy of Dr Andrew Dixon, Radiopaedia.org, rID 14567
Acute interstitial pneumonia	Dry cough Progressive dyspnea	Nonspecific	Disseminated consolidation on chest radiograph Interstitial infiltrate on chest radiograph Increased uptake on gallium scan
Pneumococcal pneumonia	High grade fever Hemoptysis Fine rales Pleuritic chest pain Increased breath sounds Bronchial breath sounds Dullness on chest percussion Purulent sputum Shallow respiration Pectoriloquy Increased tactile fremitus Productive cough Egophony	Gram positive diplococci on sputum Gram stain Pleural effusion (exudative) Respiratory alkalosis	Parenchymal hyperlucency on chest radiograph Increased uptake on gallium scan Unilateral diaphragm elevation on chest radiograph Alveolar consolidation on chest radiograph Lobar consolidation on chest radiograph
Pneumocystis carinii pneumonia	Immunosuppressive state Subcutaneous emphysema Hacking cough Progressive dyspnea	Respiratory alkalosis Serum beta-D-glucan elevation	Alveolar consolidation on chest radiograph Lobar consolidation on chest radiograph Interstitial infiltrate on chest radiograph Pneumomediastinum on chest radiograph
Pulmonary embolism	Calf pain or swelling Decreased pulse pressure Dyspnea Hemoptysis Hyperventilation Immobility Increased pulmonic component of heart sound Pleuritic chest pain Prior DVT Pulmonary hypertension Right ventricular heave Right-to-left shunt Substernal chest pain Tachypnea Thrombophlebitis Venous stasis Bone fracture	D-dimer elevation Hypocapnia Hypoxia Pleural effusion (exudative or bloody) Atrial fibrillation on ECG Right axis deviation on ECG Right ventricular overload on ECG	Normal chest radiograph Atelectasis on chest radiograph Lobar consolidation on chest radiograph Prominent pulmonary artery on chest radiograph Hampton's hump on chest radiograph Right ventricular enlargement on echocardiography Thrombus on echocardiography Segmental perfusion defect on lung scan V/Q mismatch on lung scan
Streptococcal pneumonia	Pectoriloquy Bronchial breath sounds Erythema nodosum Purulent sputum Shallow respiration Increased tactile fremitus Pleuritic chest pain Egophony	Gram-positive cocci in chains on sputum Gram stain Respiratory alkalosis Pleural effusion (exudative)	Alveolar consolidation on chest radiograph Lobar consolidation on chest radiograph Empyema on chest radiograph Increased uptake on gallium scan
Viral pneumonia	Pleuritic chest pain Bronchial breath sounds Recent influenza Fine rales Bronchovesicular breath sounds	Lymphocytosis Respiratory alkalosis	Lobar consolidation on chest radiograph Interstitial infiltrate on chest radiograph

Hampton Hump in a patient with pulmonary embolism