Lectures Flashcards
Name some risk factors which would mean people would be more likely to get URTIs
close contact, immunocompromised patients, smoking, anatomical abnormalities, hand washing, flu vaccine, diet, lack of exercise
Are URTIs self limiting?
yes
What does self limiting mean?
resolves with or without treatment.
Name the two types of barriers that pathogens have to overcome to enter the body.
Physical - hairs, cilia, mucus
Immune - adenoid, tonsils (microbes are absorbed and destroyed in them)
What defence mechanisms do pathogens have?
Produce toxins
Change their shape or outer structural proteins to disguise from being recognized (change of antigenicity).
Some bacteria may produce adhesion factors - stick to the mucus membrane and hinder their destruction.
what is the incubation time of a pathogen?
Time for pathogen to enter body until the onset of symptoms.
Symptoms of URTIs
- Nasal Congestion
- Runny nose (rhinorrhea) - more likely viral
- Nasal breathing
- Sneezing
- Sore or scratchy throat/painful swallowing (odynophagia)
- Cough (from laryngeal swelling and post nasal drip)
- Malaise
- Fever (more common in children)
When should someone be hospitalised for a URTI
• If severe and causes significant dehydration
• Respiratory difficulty with poor oxygenation (hypoxia)
Impaired swallowing.
• Significant confusion, lethargy, and worsening of shortness of breath in chronic lung and heart disease
• More common in children
Clinical examination findings for a URTI
- Swollen and redness inside wall of the nasal cavity (sign of inflammation)
- Redness of the throat
- Enlargement of the tonsils
- White secretions on the tonsils (exudates) or tongue
- Enlarged lymph nodes around the head and neck
- Redness of the eyes
- Facial tenderness (sinusitis).
- Halitosis, cough, hoarseness, fever
- Do not use a tongue depressor if you suspect epiglottitis, can induce spasm and close airway!
State some reasons for lab testing for a URTI
Suspected bacterial infection:
- bacterial cultures (nasal/throat swab, sputum)
- if strep group A is suspected then a rapid antigen testing can be done. symptoms: fever, lymph nodes in the neck, white tonsils, no cough
Suspected viral infection:
- rapid testing for the flu virus from nasal or pharyngeal swabs can be used to rule out bacterial infection and therefore unnecessary use of antibiotics.
- A heterophile antibody test can be used for Ebstein-Barr virus (Infectious Mononucleosis)
What is the normal treatment for URTIs?
Usually self limiting so patients normally self treat.
- rest
- hydration
- nutrition
Non Steroidal anti-inflammatory drugs (Aspirin/ibuprufen) –for pain/fever
Antihistamines - decrease nasal secretions
Cough meds (antitussives) – many commercially available
Honey/Menthol – may help cough
If URTI still hasn’t resolved in 10 days then antibiotics could be considered.
Describe what happens during acute bronchitis
- Inflammation of the bronchi.
- Results in ventilation/perfusion mismatch as not enough air can enter the lungs due to constriction.
- This decreases the partial pressure of oxygen in the blood and increases the partial pressure of carbon dioxide.
- These changes would be detected by the central and peripheral chemoreceptors which would increase respiration rate by hypoxic drive.
Describe what happens during pneumonia
- Swelling of lung tissue in which fluid is usually produced and fills the bronchioles or/and alveoli which reduces ability to breath properly.
- Results in a ventilation/perfusion mismatch.
- The blood stops flowing to the area of infection by vasoconstriction to increases flow in areas with good ventilation to maximize gas exchange.
what are the three complications of pneumonia
lung abscess, bronchiectasis, empyema
Describe what happens during bronchiectasis
- abnormal widening of the airways resulting in a build up of mucus making the lungs more vulnerable to risk of infection.
State some reasons for recurrent pneumonia
¥ Local Bronchial Obstruction - Tumour, Foreign body
¥ Local Pulmonary Damage - Bronchiectasis (bronchodilation)
¥ Generalised Lung Disease - Cystic Fibrosis (increase production of mucus), COPD (decrease surface area for gas exchange to occur)
¥ Non-Respiratory Disease - Immunocompromised (HIV, other), Aspiration
Describe ottis media
¥ Common, self-limiting
¥ Not “a bit pink” – RED
¥ Primary viral infection
¥ Secondary infection with Pneumococcus/ H’flu
¥ Spontaneous rupture of drum
Antibiotic treatment usually doesn’t help
Describe tonsillitis
¥ Common
¥ The dilemma is cannot tell if viral or bacterial
¥ Throat swab for lab to test
¥ Treatment: Either nothing or 10 days penicillin
¥ Don’t give amoxicillin!
What are the symptoms of croup?
Common
Coryza++ (discharge from mucus membranes), stridor, hoarse voice, “barking” cough,
What are the symptoms of epiglottitis?
Rare
Stridor, drooling- cant swallow
What pathogen causes croup?
Para flu 1
what pathogen causes epiglottitis?
H influenza Type B
What would be the treatment for croup?
Oral dexamethasone
What would be the treatment for epiglottitis?
Intubation(this can be very hard) and antibiotics
State the common viral pathogens for URTIs
Viral: ¥ Adenovirus, ¥ Influenza A, B, - flu ¥ Para’flu I, III, - croup ¥ RSV, - Respiratory Syncitial Virus ¥ Rhinovirus – common cold
State the common bacterial pathogens for URTIs
Bacterial: ¥ H influenza, - epiglottitis ¥ M catarrhalis, ¥ (Mycoplasma), ¥ (S aureus), ¥ Streptococci B haemolytic S pyogenes, Non haemolytic, S pneumonia –strep sore throat
