Pneumonia Flashcards
Describe the normal flora present in the respiratory tract
- Viridans streptococci
- Neisseria spp
- Anaerobes
- Candida sp
- Streptococcus pneumoniae
- Streptococcus pyogenes
- Haemophillus influenzae
Outline the natural defenses of the respiratory tract against infection
- Muco-ciliary clearance mechanisms - nasal hairs
- Cough and sneezing reflex
- Respiratory mucosal immune system
- Lymphoid follicles of the pharynx and tonsils
- Alveolar macrophages
- Secretary IgA and IgG
List the main infectious diseases of the upper respiratory tract
- Rhinitis (common cold) - rhinovirus
- Pharyngitis
- Laryngitis
- Epiglottis
- Sinusitis
- Otitis media
Define pneumonia
Inflammation of the lung alveoli
Describe the symptoms of pneumonia
- Fever, productive cough, pleuritic chest pain, shortness of breath, malaise, nausea
- Very similar to COPD
Distinguish between acute ‘lobar pneumonia’ and ‘broncho pneumonia’
- Bronho pneumonia - infection throughout lungs
- Lobar pneumonia - complete consolidation of a particular lobe of the lung
Briefly describe the pathogenesis of pneumonia
- If a microbe colonizes the bronchioles of alveoli, the microbe invades the lung tissue and an inflammation reaction occurs
- Leads to exudate and fluid entering lungs, neutrophil and macrophage infiltration
- Air becomes replaced with fluid and the lungs become stiff
State the main organisms which cause community acquired pneumonia
Streptococcus pneumoniae
Haemophilus influenzae
State the atypical organisms of community acquired pneumonia
- Legionella - contaminated water sources
- Mycoplasma pneumoniae - atypical as no cell wall
- Chlamydia psittaci - behaves like a virus, needs cells to develop from
State the main organisms which cause hospital acquired pneumonia
Staphylococcus aureus, E.coli, haemophilus influenzae, pseudomonas spp
Outline what you would find on examination of a patient with pneumonia
- Dullness to percussion - lung consolidation
- Pyrexia
- Tachycardia
- Tachypnoea
- Cyanosis
- Bronchial breathing
- Crackles
Outline the use of CURB-65 score in pneumonia
- Assess severity where ≥2 = severe
- Confusion
- Urea > 7mmol/L
- Respiratory rate > 30
- Blood pressure < 90 systolic, < 60 diastolic
>65 years old
Understand the principles of collection of specimens for laboratory diagnosis of pneumonias
- Sputum collection
- Blood culture - pneumoniae bacteria associated with bacteremia
- Streptococcus pneumoniae is a gram positive diplococci
- Broncho alveolar lavage fluid
- Nose and throat swabs for viruses
- Serum - antibody test
List the common opportunistic pathogens causing pneumonias in immunosuppressed hosts
- HIV - pneumocystis jiroveci
- Neutropenia - fungi such as Aspergillus spp
- Bone marrow transplant - cytomegalovirus
- Splenectomy - encapsulated organisms such as S. pneumoniae and H. influenzae
Describe the treatment for community acquired pneumonia
- Mild moderate - amoxicillin
- Moderate/severe - hospital admission, co-amoxiclav and clarithomycin/doxycycline
- Treat for both typical and atypical organisms
- Broad spectrum antibiotic + antibiotic which targets atypical organisms
- Atypical organisms do not have cell wall - cannot use penicillins
- Clarithromycin and doxycycline target protein synthesis
