Chapter 18. Fungal Diseases of the Lung. Mosby items and derived items 2011, 2006 by Mosby, Inc., an affiliate of Elsevier Inc.

Transcription

1 Chapter 18 Fungal Diseases of the Lung 1

2 YLS S M AC Figure Fungal disease of the lung. Cross-sectional view of alveoli infected with Histoplasma capsulatum. AC, alveolar consolidation; M, alveolar macrophage; S, Fungal spore; YLS, yeastlike substance. 2

3 Anatomic Alterations of the Lungs Alveolar consolidation Alveolar-capillary destruction Caseous tubercles or granulomas Cavity formation Fibrosis of the lung parenchyma Bronchial airway secretions 3

4 Etiology Histoplasmosis (Histoplasma capsulatum) Most common fungal disease in the United States Prevalence is especially high alone th major rive valleys of the Midwest Ohio, Michigan. Illinois, Mississippi, Kentucky, Tennessee, Georgia, Arkansas Histoplasmosis is also called Ohio Valley Fever 4

5 Etiology (Cont d) Screening and Diagnosis histoplasmosis Fungal culture considered the gold standard for detecting histoplasmosis Fungal stain A positive test result is 100% accurate Serology A relatively fast and accurate test 5

6 Etiology (Cont d) Coccidioidomycosis (Coccidioides immitis) Endemic in hot, dry regions: California Arizona Nevada New Mexico Texas Utah 6

7 Etiology (Cont d) Coccidioidomycosis is also known as: California Disease Desert Fever San Joaquin Valley Disease Valley Fever 7

8 Etiology (Cont d) Screening and diagnosis coccidioidomycosis Direct visualization of distinctive spherules in patient s sputum Tissue exudates Biopsies Spinal fluid 8

9 Etiology (Cont d) Blastomycosis (Blastomyces dermatitidis) Also called: Chicago disease, Gilchrist s disease, American blastomycosis Occurs in people living in the south-central and midwestern United States and Canada. 9

10 Etiology (Cont d) Screening and diagnosis Blastomycosis Direct visualization of yeast in sputum smears Culture of the fungus 10

11 Etiology (Cont d) Opportunistic pathogens Candida albicans Cryptococcus neoformans Aspergillus 11

12 Overview of the Cardiopulmonary Clinical Manifestations Associated with Fungal Diseases of the Lungs The following clinical manifestations result from the pathophysiologic mechanisms caused (or activated) by Alveolar Consolidation Increased Alveolar-Capillary Membrane Thickness 12

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15 Clinical Data Obtained at the Patient s Bedside 15

16 The Physical Examination Vital Signs Increased Respiratory rate (Tachypnea) Heart rate (pulse) Blood pressure 16

17 The Physical Examination (Cont d) Chest pain/decreased chest expansion Cyanosis Digital clubbing Peripheral edema and venous distention Distended neck veins Pitting edema Enlarged and tender liver Cough, sputum production, and hemoptysis 17

18 The Physical Examination (Cont d) Chest Assessment Findings Increased tactile and vocal fremitus Dull percussion note Bronchial breath sounds Crackles, rhonchi, and wheezing Pleural friction rub if process extends to pleural surface Whispered pectoriloquy 18

19 Clinical Data Obtained from Laboratory Tests and Special Procedures 19

20 Pulmonary Function Test Findings Moderate to Severe Cases (Restrictive Lung Pathophysiology) Forced Expiratory Flow Rate Findings FVC FEV T FEV 1 /FVC ratio FEF 25%-75 N or N or N or FEF 50% FEF PEFR MVV N or N or N or N or 20

21 Pulmonary Function Test Findings Moderate to Severe Cases (Restrictive Lung Pathophysiology) Lung Volume & Capacity Findings VT IRV ERV RV VC N or IC FRC TLC RV/TLC ratio N 21

22 Arterial Blood Gases Moderate Fungal Disease Acute Alveolar Hyperventilation with Hypoxemia (Acute Respiratory Alkalosis) ph PaC0 2 HCO 3 Pa0 2 (slightly) 22

23 PaO 2 and PaCO 2 trends during acute alveolar hyperventilation. 23

24 Arterial Blood Gases Severe Fungal Disease with Pulmonary Fibrosis Chronic Ventilatory Failure with Hypoxemia (Compensated Respiratory Acidosis) ph PaC0 2 HCO 3 Pa0 2 N (Slightly) 24

25 PaO 2 and PaCO 2 trends during acute or chronic ventilatory failure. 25

26 Arterial Blood Gases Acute Ventilatory Changes Superimposed On Chronic Ventilatory Failure Because acute ventilatory changes are frequently seen in patients with chronic ventilatory failure, the respiratory care practitioner must be familiar with and alert for the following: Acute alveolar hyperventilation superimposed on chronic ventilatory failure Acute ventilatory failure (acute hypoventilation) superimposed on chronic ventialtory failure. 26

27 Oxygenation Indices Moderate to Severe Stages Q S /Q T D02 V02 C(a-v)02 02ER Sv02 N N 27

28 Hemodynamic Indices Severe Stage CVP RAP PA PCWP CO SV N N N SVI CI RVSWI LVSWI PVR SVR N N N N 28

29 Radiologic Findings Chest Radiograph Increased opacity Cavity formation Pleural effusion Calcification and fibrosis Right ventricular enlargement 29

30 Figure Acute inhalational histoplasmosis in an otherwise healthy patient. This young man developed fever and cough after tearing down an old barn. The study shows bilateral hilar adenopathy and diffuse nodular opacities. (From Hansell DM, Armstrong P, Lynch DA, McAdams HP, eds: Imaging of diseases of the chest, ed 4, Philadelphia, 2005, Elsevier.) 30

31 Figure Histoplasmoma, showing a well-defined spherical nodule. The central portion of the nodule shows calcification. 31

32 Figure Chronic cavitary histoplasmosis. Note the striking upper zone predominance of the shadows. Numerous large cavities. 32

33 General Management of Fungal Disease The antifungal agents are the first line of defense in treating fungal lung infections. In general, the drug of choice for most fungal infections is the IV administration of the polyene amphotericin B. 33

34 Table 18-1 Antifungal Agents Agents Polyenes Amphotericin B (Fungizone) Amphotericin B colloidal dispersion (Amphotec) Common Uses (Microorganisms) Cryptococcus neoformans, Histoplasma capsulatum, Blastomyces dermatitidis, Coccidioides immitis Candida spp., Aspergillus spp., Candida spp., Aspergillus spp., mucormycosis, C. neoformans 34

35 Table 18-1 Antifungal Agents (Cont d) Agents Azoles Ketoconazole (Nizoral) Common Uses (Microorganisms) Candida spp., C. neoformans, H. capsulatum, B. dermatitidis Fluconazole Itraconazole (Diflucan) (Sporanox) Candida spp., C. neoformans Candida spp., Aspergillus spp., C. neoformans, H. capsulatum B. dermatitidis, C. immitis, Sporothrix schenckii 35

36 Table 18-1 Antifungal Agents (Cont d) Agents Echinocandins Caspofungin (Cancidas) Micafungin (Mycamine) Anidulafungin (ERAXIS) Common Uses (Microorganisms) Aspergillus spp., Candida spp. 36

37 Table 18-1 Antifungal Agents (Cont d) Agents Other Antifungals Flucytosine (Ancobon) Griseofulvin (Fulvicin) Terbinafine (Lamisil) Common Uses (Microorganisms) Aspergillus spp., Candida spp., C. neoformans Tinea corporis, tinea cruris, tinea barbae Tinea corporis, tinea pedis, tinea manuum Modified from Gardenshire DS: Rau s respiratory care pharmacology, ed 7, St. Louis, 2008, Elsevier. 37

38 Respiratory Care Treatment Protocols Oxygen Therapy Protocol Bronchopulmonary Hygiene Therapy Protocol Mechanical Ventilation Protocol 38