Unresolved pulmonary infections can be due to various causes including virulent organisms, underlying diseases, or complications. Radiology plays an important role in evaluating infections by diagnosing the location and etiology of infections, following treatment response, and monitoring complications. It is important to consider various infectious organisms, routes of infection, underlying conditions, and non-infectious potential causes of pulmonary opacities when evaluating patients with unresolved pulmonary issues.

1. Unresolved pulmonary
infections...radiological
highlights
Dr/Ahmed
Bahnassy
Consultant
Radiologist
MBCHB-MSc-FRCR

2. • 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

3. 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.

4. roles of Radiology
• Diagnose infection…
• Detection of Etiology…
• Follow up for response to treatment.
• Monitoring of complications.

5. I-Evaluation of offending
organism

6. 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?

7. 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.

8. Obstructive viral pneumonia –RSV
(note air trapping )

9. Swyer-James Syndrome

10. Laryngeotracheobronchitis..Croup
(church steeple sign)

11. 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 )

12. Bacterial lobar pneumonia

13. Bulging fissure sign

14. 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 .

15. Broncho -pneumonia

16. Bronchopneumonia - HRCT

17. 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 .

18. Lung abscess

19. what is the organism?

20. I -Nocardia Asteroids
• Organisms live
in soil.
• In
immunodeficient
state.
• Cavitation may
occur .
• Pleural effusion
in 50% .

21. II- Pneumococcal Pneumonia
• Most common G +ve.
• Air space
consolidation with air
bronchogram.
• Multifocal consistent
with
bronchopneumonia.
• Pleural effusion in <
50%.

22. 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 .

24. IV-Infective endocarditis with septic
emboli

25. V-Tuberculosis :Primary T.B.
• Ghon focus-Ranke
Complex-air space
consolidation-LNs common
in children-P. effusion may
be seen without lung
disease .

27. Necrotic LN-TB infection

29. TB variable examples

30. Cavitating pneumonia TB

31. Post Primary TB- cavitating lesion
• Cavitations in 40%.
• Pleural effusion and
LNs are uncommon.

32. Miliary TB
• Miliary spread refers
to numerous ,well
defined nodules,1-2
mm in size, diffusely
distributed throughout
the lung.

33. 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

34. Mycobacterium Avium Complex-CT
• Bronchiectasis and
centrilobular nodules .

35. VII- Histoplasmosis
• Patchy pneumonia-
Histoplasmoma with
Bull’s eye calcification.
fibrosing mediastinitis-
miliary spread)

36. VIII- Coccidioidomycosis
• May present as
consolidation +/- LN;
nodules +/- cavitate ;or
miliary pattern often with
LN

37. Coccidioidomycosis -Disseminated
• Miliary
pattern

38. IX- Blastomycosis

39. X- Cryptococcosis (in AIDS )

40. 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.

41. Invasive Aspergillosis
• Air way
invasive.
• Ill defined
nodules.

42. Angio -invasive Aspergillosis with
air crescent sign of Lung Ball.

43. Semi-Invasive Aspegillosis
• Mild immunocompromise
(TB, diabetes,mild
corticosteroid use )
• Consolidation,
• cavitation ,
• Pleural thickening ,
• +/-mass within the cavity )

44. Aspergilloma
• Saprophytic infection with
underlying structural lung
disease.
• Normal immunity.
• Haemoptysis may be life
threatening.

45. XII- Pneumocystis jiroveci (carinii)

46. Pneumocystis
• Associated with AIDS
,LowCD4 cell count.
• Perihilar GG
opacity,consolidation,pn
eumatoceles,
• pneumothorax,

47. XIII- Mycoplasma Pneumonia
• Community acquired
pneumonia.
• Patchy consolidations
or GG opacities.
• Effusion in 20%.
• LN uncommon

48. XIV -Amebic Pneumonia
• Extension from
amebic liver abscess .

49. II-Evaluating routes of
infection
• Air borne.
• Septic embolization.
• Extension from neck.
• Extension from liver.

50. Blood borne ..septic emboli
common causes?

51. by extension mediastinitis

52. 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.

53. • Necrotizing
Mediastinitis
A- 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

54. contiguous infection
• Thoraco-hepatic amebiasis

55. Take home message..Do
ultrasound
nature of effusion

56. presence of pneumonia

57. liver evaluation

58. III-Evaluation of Complications
• Empyema.
• Pulmonary
abscess.
• Bronchopleural
fistula.
• Septic
embolization.

59. Empyema after staph pneumonia

60. Empyema necessitans

61. Bronchopleral fistula after staph
pneumonia

62. Retropharyngeal cellulitis/abscess

63. Pulmonary abscess

64. 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

65. 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

66. 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.

67. Lung
sequestration
Figure 2. Axial CT images through the
area of apparent
consolidation during the administration
of IV contrast show a
mass with inhomogenous
enhancement involving the medial
aspect of the right lower lobe. There are
focal areas of low density
in keeping with necrotic regions within
the mass. There are no air
bronchograms or cavitations within the
mass. A vessel is clearly
seen to arise from the anterior aspect of
the aorta (curved arrow;
top, A), running laterally to the right, to
enter the mass

68. Bronchopulmonary sequestration

70. Di-George syndrome
absent thymus
hypocalcaemia
chronic /recurrent chest
infection

71. Cystic fibrosis

72. Immunodeficieny syndromes

73. Bronchiectasis

74. HRCT

76. V-Pulmonary opacities..
That are NOT infection

77. Causes of consolidations

78. Pulmonary lymphoma

80. Lung adenocarcinoma

81. Lung adenocarcinoma with
aerogenic spread

82. Wegener granulomatosis

83. Wegener cavitating nodules

84. Cavitating consolidations

85. Sarcoidosis

87. Eosinophilic pneumonia
acute

88. chronic

89. Summary
• Evaluate offending organism.
• Think of other routes of infection.
• Look for underlying disease or pathology.
• Evaluate occurence of complications.
• Turn to other diagnosis.

90. • Don't judge each day by the harvest you
reap, but by the seeds you plant.
• - Robert Louis Stevenson