Lower Respiratory Tract Infections Flashcards
Definitions
Acute bronchitis, exacerbation of COPD, pneumonia
Acute bronchitis
Inflammation of the bronchi, lasts less than 3 weeks. Gives cough and sputum and is usually viral, only supportive management
COPD exacerbation
Changes in sputum colour, fever, increased breathlessness and cough, wheeze. Can be caused by strep. Pneumoniae, haemophilus influenzae, viruses, moraxella catarrhalis and are treated with steroids and antibiotics and possibly nebulisers
Pneumonia pathophysiology
Inflammation of the lung parenchyma. Can be bronchopneumonia, lobar pneumonia or interstitial. Has risk factors eg extremes of age and smoking. Causes consolidation of alveoli due to increased cellular exudate, this leads to impaired gas exchange and shows on an CXR
Clinical signs and symptoms of pneumonia
Signs- tachypnoea, tachycardia, reduced expansion, dull percussion, crepitations, increased vocal resonance
Symptoms- Fever, cough and sputum(rusty brown for strep.pneu, pleuritic chest pain, dyspnoea(SOB),
Investigations for pneumonia
In community perhaps a CXR if not improving
In hospital bloods, blood cultures, CXR, sputum culture, legionella urinary antigen
What bacteria usually cause pneumonia
Strep pneumoniae, chlamydia pneumoniae, mycoplasma pneumoniae, viruses, haemophilus influenzae
Typical organisms that cause community acquired pneumonia
Pneumococcal pneumonia, haemophilus influenzae, mycoplasma pneumoniae
Atypical organisms that cause pneumonia in the community
Legionella pneumophilia (water) Chlamydia pneumoniae Chlamydia psittaci (birds) Coxiella burnetti (farm animals) Moraxella catarrhalis (COPD patients) Viruses eg flu, RSV, SARS
Organisms that cause pneumonia in nosocomial settings
Enterobacteria
Staphylococcus aureus
Pseudonomas aerigunosa (horrible sputum)
Klebisella pneumoniae
How do we score severity of pneumonia
C - confusion U - urea in blood >7mmol/L R - respiratory rate ≥ 30/min B - BP less than 90/60 65 - age over 65
Score 2-5 usually hospital
3-5 death risk is 15-40%
CURB 0-1 pneumonia treatment
Amoxicillin or clarythromicin/doxycycline for 5 days
CURB 2 pneumonia treatment
Amoxicillin and clarythromicin, levofloxacin if allergy for 5-7 days
CURB 3-5 pneumonia treatment
Co-amoxiclav and clarythromicin for 7-10 days
Special circumstances in pneumonia
Aspiration pneumonia eg stroke, MS, heavy drinking - anaerobes likely
Immunocompromised eg aspergillus fumigatus candida
MRSA - use vancomycin
Complications of pneumonia
Sepsis, kidney injury, ARDS, parapneumonic effusion (do CXR and aspirate, may need drain), abscess (staph aureus, Pseudonomas, anaerobes with purulent sputum), empyema
Bronchiectasis
Dilatation of bronchi with lots of mucus, can be idiopathic, childhood infection, cystic fibrosis. Causes chronic productive cough, breathlessness, recurrent LRTI, haemoptysis, finger clubbing, crepitations, wheeze and obstructive spirometry
Common LRTI presentation in children
Cough, wheeze, fast breathing
Laryngotracheobronchitis (croup) presentation in kids
Very common, viral narrowing of large airways. Inspiratory stridor, hoarseness, preceding cough and fever. Worse at night, 6m-6y
Management of croup
Supportive with reassurance and safety netting. One off dose of dexamethasone (steroid)
Bacterial tracheitis in kids
Uncommon, croup that doesn’t get better, strep or staph, give co-amoxiclav
Bacterial epiglottis in kids
Rare, high fever toxic child, drooling and leaning forward with sore throat
Bronchiolitis (RSV)
Respiratory Syncytial Virus
Very common esp winter, inflammation, congestion, mucus, cold symptoms then cough, crackles and perhaps wheeze. Managed same as croup but admitted if worse symptoms for oxygen, no CXR or bloods needed
Whooping cough (bordatella pertussis)
Common as vaccine only reduces risk and severity. Cold like then coughing fits with red face and vomit, inspiratory whooping sound. Is a bacterial notifiable disease and treat with macrolides
