Pulmonary Infections in the immune compromised host

Question 1

What are some immunodeficiency states?

Answer 1

• Lymphoma, leukemia • Other malignancies and associated chemotherapy • Organ transplants and associated immunosuppressive therapy • Neutropenia • Immunosuppressive drugs – Steroids • Other immunocompromised states – Hypogammaglobulinemia – Collagen-Vascular – Asplenia – AIDS

Question 2

Defects in local defenses can cause what problems?

Answer 2

Cystic fibrosis and Immotile cilia

Question 3

What is the clinical pattern of infection with Cystic Fibrosis? what organisms?

Answer 3

Chronic Pulmonary Infection S. aureus Mucoid P. aeruginosa

Question 4

What is the clinical pattern of infection with immotile cilia? Organisms?

Answer 4

Frequent Mild Respiratory Infections: GPC, GNB

Question 5

What are some diseases that are phagocytic disorders in the lungs? what are their clinical manifestations? Organisms?

Answer 5

1. Chronic Granulomatous Disease: Chediak-Higashi Syndrome, Job syndrome Recurrent pyogenic Disease infections of the skin and other RES (pulmonary, bone) sites Catalase positive organisms (S.aureus, Salmonella) GNB, fungus streptococci

Question 6

What are some Humoral Defects diseases and what clinical manifestations do they cause? what are the organisms?

Answer 6

1). antibody deficiency 2). Complement deficiency: C3-C5, C7-C9, alternative pathway. Recurrent Respiratory and other infections C3-C5: S. Aureus, GNB, S. Pneumonia C7-C9: Neisseria Pneumonia Alternative: S. Pneumonia, Salmonella.

Question 7

Name some diseases with cellular defects and their clinical manifestations and organisms?

Answer 7

1). Digeorge syndrome 2). Wiskott-Aldrich 3). Ataxia Telangiectasia 4). AIDS Life Threatening respiratory and generalized infections with obligate intracellular organisms GNB, Listeria, Cryptococcus, Histo, Herpes group, Pneumocystis, Toxoplasmosis, strongyloides, S. pneumoniae, S. Aureus, H. influenzae, Mycobacteria, CMV, Candidasis, Cryptococcus, Toxoplasma, Cryptosporidium

Question 8

List the infectious causes of pulmonary infiltrates?

Answer 8

– Bacterial • S. aureus, GNB, Legionella, Nocardia – Viral • CMV, Herpes simplex, Adenovirus, Varicella-zoster – Fungal • Cryptococcus, Aspergillus, Mucormycosis, Candida – Mycobacterial • M. tuberculosis, Atypical Mycobacteria – Parasitic • Pneumocystis, Strongyloides, Toxoplasma

Question 9

Non-infectious causes of pulmonary infiltrate?

Answer 9

– Pulmonary edema – Cytotoxic drug-induced lung injury – Radiation pneumonitis/fibrosis – Leukostasis – Leukoagglutinin reaction – Spread of underlying neoplasm – Leukemic cell lysis – Pulmonary hemorrhage

Question 10

Explain the PE findings of the chest and extra thoracic regions in the immunocompromised person?

Answer 10

• Chest exam – Rales audible before chest infiltrates – Localized wheezes suggests endobronchial lesion – Pleural friction rub with pulmonary infiltrate suggests virulent GNB or fungus – Respiratory rate sensitive of severity • Extrathoracic Exam – Skin: Ecthyma Gangrenosum (pseudomonas, aspergillus), Cutaneous papules (cryptococcus, nocardia) – Retinal Lesions: CMV, Candidiasis, Aspergillosis – Necrotizing Nasal Lesions: Mucor, Aspergillus, GNB – CNS: Meningitis (cryptococcus, tuberculosis, cancer), space occupying (nocardia, mucor, cancer), encephalitis (herpes, toxoplasmosis)

Question 11

What are the rapid tempo pulmonary infections in the immunocompromised host?

Answer 11

Pneumocystis Bacterial (GNB, staph aureus, legionella).

Question 12

What are the subacute tempo pulmonary infections in the immunocompromised host?

Answer 12

CMV, Aspergillus, Mucor

Question 13

What are the insidious tempo pulmonary infections in the immunocompromised host?

Answer 13

Nocardia, Cyrptococcus, Tuberculosis

Question 14

What can cause localized or lobular infiltrates on radiology of the lung?

Answer 14

– Infection • Bacterial • Fungal • Mycobacterial – Hemorrhage – Neoplasm • Lymphoma • Bronchogenic carcinoma – Infarction • Bland (usually single) • Septic (usually multiple)

Question 15

What things can lead to diffuse pulmonary infiltrates in the lung?

Answer 15

– Infection • P. jiroveci pneumonia • Viral pneumonia • Sepsis with bacteria or fungus – Hemorrhage – Neoplasm • Leukemic infiltration • Lymphangitic carcinoma – Drug toxicity – Pulmonary edema • Cardiac • Noncardiac – Pleural effusion • Congestive heart failure • Pulmonary embolus • Bacterial pneumonia

Question 16

What are some things that lead to cavitation on radiology in the immunocompromised patient’s lungs?

Answer 16

– Anerobic infection – Primary lung cancer – Fungal pneumonia – Lymphoma – Tuberculosis – Pulmonary infarctions – Septic emboli (bacterial or fungal) – Nocardia

Question 17

what molecular techniques to diagnose pneumonia in the immunocompromised host?

Answer 17

– Skin tests • No value – Serology • Antibody Tests – CMV – Legionella » Need acute and convalescent tests » Elisa, RIA for Ag in urine – Fungal infections » Not useful • Antigen Tests – Cryptococcus » Latex agglutination – Fungal infections (candida, aspergillus) – Parasitic infections » Pneumocystis

Question 18

What are the pulmonary diagnostic techniques to diagnose pneumonia?

Answer 18

– Routine Sputum – Pulmonary Diagnostic Techniques • Sputum induction by hypertonic saline • Transtracheal aspiration • Fiberoptic bronchoscopy (double catheter brush) – Bronchoalveolar lavage – Transbronchial biopsy – Specimen for quantitative cultures • Needle aspiration biopsy • Open lung biopsy (gold standard)

Question 19

Explain Transtracheal Aspiration: What needle? Recommended when? Limitations? Complications?

Answer 19

– Transtracheal Aspiration • 16-18 gauge needle into cricothyroid membrane • Recommended – Unable to make sputum – Routine sputum has contaminants – Sputum negative cases (tuberculosis, fungi) • Limitations – False positive of 4% – False negative of 24% (50% on prior antibiotics) • Complications – Subcutaneous emphysema –0.5% – Significant hemorrhage – 0.2% – Paratracheal infection – 0.2%

Question 20

Fiberoptic bronchoscopy: When is it recommended? Specificity? Complications?

Answer 20

Fiberoptic Bronchoscopy • Recommended – Central diffuse or focal lesions – No specimen by sputum or transtracheal – No response to antibiotic therapy • Specificity – Transbronchial biopsy 41% – Bronchial brushing 27% – Combined 52% – Bronchoalveolar lavage • Complications – Hemorrhage 7% – Pneumothorax 7%

Question 21

When is aspiration lung biopsy recommended? Contraindicated? Complications?

Answer 21

– Aspiration Lung Biopsy • Recommended – Focal, peripheral lung infiltrates – Fluoro directed aspirations: 70-90% accurate – 64% false negative rate • Contraindicated – Inadequate platelets or coagulation – Uncooperative patient – Bullous emphysema • Complications – Pneumothorax 25% – Self-limited hemoptysis 2-5% – Local bleeding at site 11%

Question 22

Open lung biopsy specificity? non-specific diagnosis? Recommended when? Complications?

Answer 22

– Open Lung Biopsy • Specificity 55-91% (69%) • Nonspecific Diagnosis 13-45% (32%) • Recommended – Diffuse or focal infiltrates – Where other techniques have failed or given nonspecific diagnosis • Complications – Pneumothorax 8% – Bleeding (rare) – Mortality 0.6%

Question 23

When doing a gram stain and cultures for the sputum explain what tests are done and what they are testing for? What bacteria are always pathogenic and which are colonizers?

Answer 23

– Gram stain • Acid fast (Ziehl Neelson, Kinyoun) Mycobacteria • India ink –cryptococci • Methenamine silver or Toluidine blue 0 – cyst walls of pneumocystis • Direct fluorescent antibody staining –Legionella • KOH – Fungi • Papanicolou stains –cancer cells – Cultures Always pathogenic – Aspergillus, Nocardia, Cryptococcus • Colonizers – Gram negative bacilli, Staph sp., Candida

Question 24

How do we recognize the pulmonary infection in Immunocompromised people?

Answer 24

– Presenting symptoms may be systemic • Fever, night sweats, weight loss – Pulmonary symptoms • Dyspnea, nonproductive cough (subtle) – Onset may be very gradual – Physical exam of lung rarely helpful • Less sensitive than symptoms or lab – Routine tests may not be sensitive for early disease • Chest x-ray

Question 25

What are common bacteria that could cause lower respiratory tract problems in

Answer 25

• Common (>10%) – Pneumocystis jiroveci – Cytomegalovirus (b) – M. avium complex (b)

Question 26

What are uncommon bacteria that could cause lower tract respiratory problems?

Answer 26

Uncommon (<10%) – Cryptococcus neoformans – Histoplasma capsulatum – Coccidioides immitis – Herpes simplex virus (b) – Adenovirus – Legionella sp. – M. tuberculosis – Toxoplasma gondii (a) – Pyogenic bacteria – Cryptosporidium (a)

Question 27

Explain Pneumon

Answer 27

–Pneumocystis jiroveci • Unicellular protozoa acquired early in childhood from environmental exposure. • Most infection is from reactivation of latent disease. – Most common opportunistic pathogen in AIDS » More than 80% AIDS patients will acquire. – Symptoms » Dyspnea, nonproductive cough, fever, tachypnea.

Question 28

Explain Pneumoncystis jiroveci?

Answer 28

–Pneumocystis jiroveci • Unicellular protozoa acquired early in childhood from environmental exposure. • Most infection is from reactivation of latent disease. – Most common opportunistic pathogen in AIDS » More than 80% AIDS patients will acquire. – Symptoms » Dyspnea, nonproductive cough, fever, tachypnea.

Question 29

Lab evaluation and diagnosis for Pneumocystis Jiroveci?

Answer 29

Specific Pulmonary Infections –Pneumocystis jiroveci • Lab evaluation – Chest x-ray (normal, butterfly, intra-alveolar infiltrates) – Positive gallium scan – Abnormal PFT (decreased DLCO) – Abnormal blood gases • Diagnosis – Induced sputum (one study = 61%) – Bronchoalveolar lavage and biopsy – Open lung biopsy (needed <5%)

Question 30

Explain Mycobacterium Tuberculosis? Recognition, groups? sites? Therapy?

Answer 30

• Mycobacterium Tuberculosis – Reactivation disease in high risk groups • Haitian immigrants – Disease sites • Lung (local or miliary) • Bacteremia – Recognition • Acid fast smear (mycotuberculosis vs. MAI) • Cultures – Therapy • INH, Rifampin, Ethambutol x 1 year

Question 31

CMV findings? effect on survival? non-pulmonary disease? Therapy?

Answer 31

– CMV found in 33% of bronchoscopies in AIDS • Actual histologic evidence inclusion bodies small percentage • Presence has no effect on survival (limited pathogenic role in lung) – Nonpulmonary disease • Retinitis, colitis, adrenalitis, GI ulceration, encephalitis – Therapy • DHPG (colitis, retinitis)

Question 32

Cryptococcus Neoformans: look for? histo area found? Coccidimycosis location? herpes simplex pneumonia dissemination?

Answer 32

• Cryptococcus Neoformans – Rarely causes isolated pulmonary disease • Look for fungemia, meningitis • Disseminated Histoplasmosis – Southeastern USA • Disseminated Coccidimycosis – Southwestern USA • Herpes simplex pneumonia – Absence of dissemination

Question 33

Toxoplasma gondii is usually found with? Cryptosporidium presents with?

Answer 33

• Legionella – Varies with region • Toxoplasma gondii – In conjunction with CNS disease • Cryptosporidium – Usually gastrointestinal – Rare isolated pneumonitis

Question 34

Explain Skin, Neuro, Eyes, and Nasal abnormal findings with what causes them in pneumonia in the immunocompromised patient ?

Answer 34

– Skin lesions • Ecthyma gangrenosum (GNB, fungal) • Papules, nodules (cryptococcus, nocardia, neoplastic) – Neurologic abnormalities • Space occupying brain (nocardia, mucor, neoplastic) • Encephalitis (herpes, toxoplasmosis) • Meningitis (cryptococcus, TB, neoplasia) – Eye abnormalities • Yellow-white retinal patches with surrounding hemorrhage(CMV) • Discrete choroidal lesions (candida, aspergillus) – Nasal abnormalities • Necrotizing with septal perforation • Mucormycosis, aspergillosis, invasive GNB

Question 35

Explain the Thoracic involvement in AIDS-associated Kaposi’s Sarcoma?

Answer 35