Radiological Imaging in pneumonia and its complications

Transcription

1 Radiological Imaging in pneumonia and its complications Cornelia Schaefer-Prokop Meander Medical Center Amersfoort Radboud University Nijmegen Netherlands

2 Outline Radiographic patterns Infections in immunocompromised patients Complications

3 Radiographic Classification Bronchopneumonia Lobar pneumonia (alveolar) Interstitial pneumonia (interstitial) Cave: OVERLAP

4 Bronchopneumonia The most common pattern Lobular Pneumonia Multifocal and centered around inflamed airway, involving some acini and sparing others Patchy consolidation and no air bronchogram, they may confluent and resemble lobar pneumonia Organisms: Staphylococcus aureus, gram-negative organisms, anaerobic bacteria, Mycoplasma, Legionella

5 Lobular (Broncho)pneumonia (Staphylococcus aureus)

6 Bronchopneumonia (Mycoplasma)

7 Lobar pneumonia Inflammation starts in the distal air ways and expands over Kohn sche pores Homogeneous, non-segmental consolidation with air bronchogram, complete / incomplete lobe Organisms: Streptococcus pneumoniae, Klebsiella, Legionella, Mycoplasma pneumoniae

8 Lobar pneumonia

9 Interstitial Pneumonia Extended bilateral peribronchial thickening and reticulo-nodular shadows CT: ground glass, micro-nodular, tree in bud Organisms: Viral, Mycoplasma, Pneumocystis

10 HIV-positive, Pneumocystis pneumonia

11 Role of Imaging CXR: diagnosis and/or assessment of - presence and extent of opacification - differentiation between bronchitis vs. pneumonia - prognosis esp. in high risk patients - therapy control CT: diagnosis and/or assessment of - alternative diagnosis (e.g., PE) - underlying malignancy - complications: empyema, BPF

12 Risk Stratification Pneumonia severity index clinical prediction rule for morbidity/mortality in CAP Curb 65 (Brit. Soc of pulmonologists) Confusion of new onset Urea greater than 7 mmol/l (19 mg/dl) Respiratory rate of 30 breaths per minute or greater Blood pressure < 90 mmhg systolic or diastolic blood pressure <60 mmhg age 65 or older Independent risk factors for treatment failure and inhospital mortality: liver disease, leucopenia, multilobar CAP, pleural effusion, and cavitation Menendez R et al. Thorax 2004, 59, 960

13 Definitions CAP = community acquired pneumonia pneumonia in an out-patient Nosocomial pneumonia pneumonia in an in-patient (> 48 hours) Opportunistic pneumonia pneumonia in an immunocompromised patient Atypical pneumonia CAP, which requires spec. antibiotics (macrolide and tetracycline) Legionella, Mycoplasma, Chlamydia, Protozoa

14 Specific Patient Groups Elderly patient Children COPD Smoker Cardiac patient Mild immune -deficiency less symptoms but higher risk aspecific symptoms exacerbation of chr. bronchitis exclusion of an underlying malignancy comorbidity causes higher risk Diabetes, alcoholism, malnutrition

15 Specific agents.. radiologic pattern

16 2 out-patients, high fever, consult the family doctor Xray Streptococcus pneumoniae

17 Elderly lady, very dyspnoic, admission to the ER What is your differential diagnosis?

18 Pneumococcus Pneumonia Air bronchogram Bulging fissure Positive angiogram sign

19 Take-home points The presence of air bronchogram indicates a pulmonary origin of the opacification Lack of an airbronchogram does not necessarily mean that the opacification is non-pulmonary Atelectasis of almost the complete lung causes mediastinal shift

20 Legionellaires Disease DD: lobar pneumonia 2-25% of CAP, requires hospitalization In elderly, patients with malignancies Lobar pneumonia Fast bilateral spread Legionella test

21 Klebsiella DD: lobar pneumonia 1-5% of CAP but more common in alcoholism and chr. bronchopulm. disease Bulging fissure (30%) Pleural effusion (60%) Abscess, cavitation and empyema

22 Bronchopneumonia: Mycoplasma DD: lobular pneumonia

23 Bronchiolitis: Mycoplasma

24 Lobular Pattern in HRCT Random Tb Perilymphatic Sarcoidosis Tree-in-bud Bronchiolitis

25 Chlamydia vs. Mycoplasma acinar nodules ground glass consolidations centrilobular nodules bronchial wall thickening From Okada F et al. JCAT 2005,29(5):626

26 Haemophilus influenzae gram neg coccobacillus Up to 20% of CAP Risk factors: diabetes, acoholism, COPD 60% bronchopneumonia 40% lobar pneumonia In > 50% effusion Cavitation in up to 15% Rarely empyema

27 Take home points: CAP Str Pneumoniae 40% lobar pneumonia H Influenza 25% COPD, bronchopn. Atypical 20% in young adults (mycoplasma, bronchopn, but also chlamydia) confluent Klebsiella 5% predisposition, abcess Legionella 2-20% fast spread, ill!

28 Pneumonia in the immunocompromised Patient

29 The Immuno-compromised Patient bone marrowtransplantation organ transplantation chemotherapy immunosuppressive therapy splenectomy diabetes sarkoidosis malnutrition alcoholism renal/liver insufficiency HIV

30 The Immuno-compromised Patient 1. Granulozytopenia / dysfunction neutropenia, sarkoid, alcohol, diabetes, SLE Staph, gram-neg bacteries, Aspergillus 2. T-cell-dysfunction HIV, BM-Tx, Thymus aplasia, steroids, PcP, CMV, Tb, Aspergillus, Nocardia 3. B-cell-dysfunction organ-tx, nephrot. syndrome, splenectomy, lymphoma Strept pneum. Hemoph. Infl.

31 Role of Imaging Chest radiograph Screening, first imaging but not very sensitive (in 40% negative) HRCT more sensitive pattern analysis is helpful for classification differential diagnosis follow-up / therapy control complications

32 Bacterial Infections Lobular/ lobar consolidations Air bronchogram but with bad immune status only ground glass Staph. aureus, gramneg. bact, Klebsiella >>> S. pneumoniae, H. Influenzae Frequently mixed infections

33 Septic Emboli (endocarditis, drug addict)

34 Take home points In immune-incompetent patients - any bacterial infection is possible - may present atypically - increased risk for gramnegative bacteries and complications - opportunistic infections

35 Fungal infections Patients with... - neutropenia (under chemotherapy) - Cortison therapy - GVHD - AIDS - BM-Tx

36 Angio-invasive Aspergillus Halo Consolidations Air crescent

37 Neutropenic patient: aspergillus??

38 It may start small

39 There has to be an adequate clinical situation! Multiple opacifications Halo???? Bacterial bronchopneumonia in a COPD patient

40 Endobronchial Aspergillus more rare!

41 Fungal infection...but not aspergillus... Candida sepsis

42 Fungal Infections Take home points 1. Aspergillus the most frequent one 2. Halo / bronchovascular distribution / air crescent sign 3. Cave: endobronchial fungal infection with bronchiolitis (Tree-in bud) 4. Look at extrapulmonary findings

43 Crytococcus Infection Congenital immunedeficiency, back pain

44 Role of Imaging: Caveats There might be a delay of several hours (12h) between onset of symptoms and presence of opacifications In up to 10% negative CXR despite clinical symptoms, in immunoincomptetent patients negative CXR in up to 40%. No or delayed opacification in patients with reduced immune competence (diabetes, alcohol, neutropenia) Atypical pattern in patients with pre-exisiting lung disease (emphysema, fibrosis)

45 Role of preexisting lung disease Pneumococcus Pn. in emphysema Idiopathic fibrosis (UIP)

46 Pneumonia: Complications Empyema Abcess Bronchopleural fistulal

47 HIV pos patient: more imaging needed?

48 The importance of CT for complications HIV+, Bacteroides

49 Pleural Fluid Collections Uncomplicated that resolve with conservative therapy transudative effusions small free-flowing exudative effusions Complicated do not resolve without drainage moderate to large unilocular or multilocular parapneumonic effusions Empyema malignant effusions hematothoraces

50 Complicated Pleural Effusion

51 Pleural Infection in CT Pleural enhancement / thickening (split pleura sign) Increased extrapleural fat with increased attenuation Pleural adhesions / (fibrious septations) Loculations (air bubbles) DD pulmonary abscess from pleural empyema

52 Which one is the empyema? A: Hemato thorax B: empyema C: pulm. abscess D: chr effusion in RA

53 Anaerobic Bacteria typically after aspiration 20-35% of CAP, requires hospitalization In > 30% of nosocomial infection Risk: impaired consciousness Bronchopneumonia posterior upper lobe and apical lower lobe In 20-60% abscess formation, In 50% effusion and empyema

54 Day 1 day 2

55 Day 7

56 Nosocomial Pneumonia Infection > 48 h after hospitalization IC: 10-65%, of which 20-55% fatal ARDS: in 55% complicated by sec. infection Aspiration: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Anaeroben Septic emboli: Staphylococcus aureus

57 Aspiration pneumonia ARDS

58 Conclusion Overlap of radiologic pattern and underlying type of infectious agents Differentiation between bacterial vs. fungal vs. viral infection under immunosuppression Role of imaging is to sort out differential diagnosis and to look for complications