Unresolved pulmonary infections..radiological highlights
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Transcript of Unresolved pulmonary infections..radiological highlights
Unresolved pulmonary infections...radiological
highlights
Dr/Ahmed Bahnassy
Consultant Radiologist
MBCHB-MSc-FRCR
• Success is to be measured not so much by the position that one has reached in life... as by the obstacles which he has overcome while trying to succeed.
• - Booker T. Washington
Unresolved pneumonia
failure of pneumonia to resolve can be due to:
1.virulent ,or undiagnosed organism.2.underlying disease process or pathology.3.Occurence of complications.4.Other diagnosis than infection.
roles of Radiology
• Diagnose infection…• Detection of Etiology…• Follow up for response to treatment.• Monitoring of complications.
I-Evaluation of offending organism
Radiological Patterns• Pathologically pulmonary infections can be
divided into infections involving :central air ways ,small air ways and pulmonary parenchyma.
• Pneumonia is subdivided into :lobar ,broncho and interstitial pneumonia .
• Lung abscess is an additional pattern seen with lobar or bronchopneumonia
where the infection?
I- Bronchiolitis• Inflammation of small air
ways (membranous and respiratory bronchioles).
• Caused by viruses (RSV is most common).
• Acute bronchiolitis ,causd by adenovirus ,may cause constrictive bronchiolitis ,chronic bronchiolitis, bronchiectasis. .forming a syndrome called Mc leod syndrome.
Obstructive viral pneumonia –RSV (note air trapping )
Swyer-James Syndrome
Laryngeotracheobronchitis..Croup (church steeple sign)
II-Lobar pneumonia.• Caused by streptococcal
or Klebsiella pneumoniae .
• Begins by a peripheral opacity that evolves into a confluent ,consolidation.
• Expansion of the lobe can cause bulging fissure ( associated with Klebsiella pneumoniae )
Bacterial lobar pneumonia
Bulging fissure sign
III-Bronchopneumonia• Begins with infection of air
way mucosa ,then extends into adjacent alveoli .
• Present as ill defined air space nodules or patchy areas of consolidation.
• Caused by virulent organism …( Staph aureus ,or G –ve organisms )
• Can develop abscess.• Result in scarring .
Broncho -pneumonia
Bronchopneumonia - HRCT
IV-Lung Abscess• Localized infection that
undergoes tissue destruction and necrosis.
• Cavitations and air fluid level can occur due to communication with tracheobronchial tree .
• Caused by mixed anaerobic infections , S.aureus ,and Pseudomonas aeruginosa.
• Multiple abscesses may result from septic emboli .
Lung abscess
what is the organism?
I -Nocardia Asteroids
• Organisms live in soil.
• In immunodeficient state.
• Cavitation may occur .
• Pleural effusion in 50% .
II- Pneumococcal Pneumonia
• Most common G +ve.• Air space
consolidation with air bronchogram.
• Multifocal consistent with bronchopneumonia.
• Pleural effusion in < 50%.
III- Staph Pneumonia• Common cause of
nosocomial infection.• Usually
bronchopneumonia with patchy lower lobe consolidation.
• Cavitation frequent.• Pnematoceles may be
seen.• Septic emboli.• Pleural effusion in
50%,Empyema may result .
IV-Infective endocarditis with septic emboli
V-Tuberculosis :Primary T.B.• Ghon focus-Ranke
Complex-air space consolidation-LNs common in children-P. effusion may be seen without lung disease .
Necrotic LN-TB infection
TB variable examples
Cavitating pneumonia TB
Post Primary TB- cavitating lesion
• Cavitations in 40%.• Pleural effusion and
LNs are uncommon.
Miliary TB• Miliary spread refers
to numerous ,well defined nodules,1-2 mm in size, diffusely distributed throughout the lung.
VI-Mycobacterium Avium Complex
• I-Resembles TB, occurs in old men with COPD or mild immunodepression.
• II-Bronchiectasis and nodules in lingula or middle lobe.
• III-GG opacity and small nodules with hypersensitivity pneumonitis .
Lady Windermere syndrome
Mycobacterium Avium Complex-CT
• Bronchiectasis and centrilobular nodules .
VII- Histoplasmosis• Patchy pneumonia-
Histoplasmoma with Bull’s eye calcification. fibrosing mediastinitis-miliary spread)
VIII- Coccidioidomycosis
• May present as consolidation +/- LN; nodules +/- cavitate ;or miliary pattern often with LN
Coccidioidomycosis -Disseminated
• Miliary pattern
IX- Blastomycosis
X- Cryptococcosis (in AIDS )
XI- Aspegillosis :Invasive Aspergillosis -Halo Sign
• Neutropenia present.
• Patchy consolidations with halo sign in Angio-invasive form
• Centrilobular nodules ,tree in bud in airway invasive form.
Invasive Aspergillosis
• Air way invasive.
• Ill defined nodules.
Angio -invasive Aspergillosis with air crescent sign of Lung Ball.
Semi-Invasive Aspegillosis• Mild immunocompromise
(TB, diabetes,mild corticosteroid use )
• Consolidation,• cavitation ,• Pleural thickening ,• +/-mass within the cavity )
Aspergilloma
• Saprophytic infection with underlying structural lung disease.
• Normal immunity.• Haemoptysis may be life
threatening.
XII- Pneumocystis jiroveci (carinii)
Pneumocystis
• Associated with AIDS ,LowCD4 cell count.
• Perihilar GG opacity,consolidation,pneumatoceles,
• pneumothorax,
XIII- Mycoplasma Pneumonia
• Community acquired pneumonia.
• Patchy consolidations or GG opacities.
• Effusion in 20%.• LN uncommon
XIV -Amebic Pneumonia
• Extension from amebic liver abscess .
II-Evaluating routes of infection
• Air borne.• Septic embolization.• Extension from neck.• Extension from liver.
Blood borne ..septic embolicommon causes?
by extension mediastinitis
Danger Space• Danger Space
– Anterior border is alar layer of deep fascia
– Posterior border is prevertebral layer
– Extends from skull base to diaphragm and is so named because it contains loose areolar tissue and offers little resistance to the spread of infection.
• Necrotizing MediastinitisA- MDCT of the neck shows two large fluid collections containing gas in both the submandibular spaces (arrows).(B) At the level of the hyoid bone, a large fluid collection is seen in the visceral space (C) Large fluid collection in the visceral space (D) The fluid collection spreads to the anterior mediastinum (E) Sagittal multiplanar reformatted CT image shows spread of descending necrotizing mediastinitis
contiguous infection
• Thoraco-hepatic amebiasis
Take home message..Do ultrasound
nature of effusion
presence of pneumonia
liver evaluation
III-Evaluation of Complications
• Empyema.• Pulmonary
abscess.• Bronchopleural
fistula.• Septic
embolization.
Empyema after staph pneumonia
Empyema necessitans
Bronchopleral fistula after staph pneumonia
Retropharyngeal cellulitis/abscess
Pulmonary abscess
IV-Evauating recurrent/chronic pulmonary problems in pediatrics
Mechanism Causes
1. Aspiration CNS malformation-cerebral tumors-Tracheo-esophageal fistula-Reflux
2.Anomaly Congenital lobar emphysema-Sequestration-Tracheobronchial tree anomalies(tracheal bronchus-stenosis-atresia)-bronchogenic cyst.
3.Allergy. Astham- Loeffler pneumonia-allergic alveolitis
4.Systemic disease. Cystic fibrosis
5.Immunodeficiency. Prematurity-AIDS-Neutropenia
6.Physical agents. Foreign body-Drugs-radiation-Bronchopulmonary dysplasia
7.Neoplasm. Leukemia-Lymphoma-Histiocytosis
8.CVS Left to right shunt -PA stenosis-vascular ring
9.specific Infections. TB-Mycoplasma-Bronchiectasis
10.Miscellaneous Interstitial Pneumonia-Collagen vascular disease-Alveolar proteinosis-sarcoidosis.
special problem
Role of Radiology • The role of radiology is 3 folds :• 1 .Evaluate the present X-ray.• The presence and distribution of opacities,• Pleural involvement ,Lymph nodal swellings ,pulmonary vascularity ,soft
tissue involvement , bony structures .• 2.Review of previous films.• Are the lesion stable in the same location (Sequestration ?)• Are they present always in upper lobe (aspiration ? )• Are they changing in location (Immunodeficiency ?)• 3.Perform esophagogram.• Reflux of gastric contents.• Abnormal peristalsis.• Compression of esophagus by a mass ,vascular ring.• Tracheo-esophageal fistula.• Hiatal Hernia
Recurrent right basal consolidation
• Posteroanterior (top, A) and lateral (bottom, B) chest
• radiographs demonstrate an area of ill-defined consolidation
• involving the medial segment of the right lower lobe.
Lung sequestrationFigure 2. Axial CT images through the
area of apparentconsolidation during the administration
of IV contrast show amass with inhomogenous
enhancement involving the medialaspect of the right lower lobe. There are
focal areas of low densityin keeping with necrotic regions within
the mass. There are no airbronchograms or cavitations within the
mass. A vessel is clearlyseen to arise from the anterior aspect of
the aorta (curved arrow;top, A), running laterally to the right, to
enter the mass
Bronchopulmonary sequestration
Di-George syndrome
absent thymushypocalcaemiachronic /recurrent chest infection
Cystic fibrosis
Immunodeficieny syndromes
Bronchiectasis
HRCT
V-Pulmonary opacities..That are NOT infection
Causes of consolidations
Pulmonary lymphoma
Lung adenocarcinoma
Lung adenocarcinoma with aerogenic spread
Wegener granulomatosis
Wegener cavitating nodules
Cavitating consolidations
Sarcoidosis
Eosinophilic pneumoniaacute
chronic
Summary
• Evaluate offending organism.• Think of other routes of infection.• Look for underlying disease or pathology.• Evaluate occurence of complications.• Turn to other diagnosis.
• Don't judge each day by the harvest you reap, but by the seeds you plant.
• - Robert Louis Stevenson