L19 URTI Flashcards
Put respiratory infections
influenza, Cold - (nose throat sinus), bronchiolitis (croup), pneumonia, pharyngitis and tuberculosis
in order of most common to least and is it more common in children or adults
- Colds - 6/yr in kids. Half that in adults
- Bronchiolitis- virus infection with SOB, harsh cough. - 100% by 3yrs.
- Pharyngitis- 30%/yr in childhood
- Influenza 15%/yr
- Pneumonia: in children 5/1000. Adults 2/1000/yr
- Tuberculosis
What are the main types of URTI and what event precedes the bacterial infection of these areas. (4)
- Sinusitis: inflammation causes closing of the osteum which may lead to bacterial sinusitis
After swelling of the mucus causing blockage of airways, including nose.
- Pharyngitis/tonsilitis: may involve soft palate, tonsils, uvula. Can have submandibular lymphadenopathy.
- Otitis media: after blockage of the eustachian tube, accumulation of mucus which can lead to bacterial infection
- Tracheitis
What are the potential viral and bacterial causes of pharyngitis.
Differentiate between them: severity of illness, focus of illness, signs
50% bacterial: Strep. Pyogenes: (THROAT ONLY)
- More severe illness, fever, pain, dysphagia, adenopathy
- Focal pharyngeal infection, red pharynx
- more common in school age children
- assymptomatic colonisation of pharynx in 16%, with repeated episodes of infection due to different M types.
50% Viral: Pharyngitis due to rhinoviruses/ RSV, Influenza, Coronaviruses
- Less severe illness
- More diffuse URTI rhinorrhoea, hoarse voice, cough, conjunctival signs.
What are the 3 types of haemolysis results and give examples of the main bacteria that cause it.
- Alpha haemolysis: partial - green surrounding colonies
eg. Strep. pneumoniae
Strep. Viridans
- Beta haemolysis: complete - clear surrounding colonies.
eg. Strep Pyogenes,, B, C and G strep. - Gamma haemolysis: no haemolysis
eg. Enterococcus faecalis.
How does lance field serogrouping differentiate between streptococci and what URTIs do Strep pneumoniae and Haemophilus influenzae cause
Using antibodies which will cause agglutination of sample with specific surface protein related to a specific strep group
S. pneumoniae is batman of Otitis media, sinusitis, pneumonia. Hib is the Robin
What are common respiratory viruses and What is the typical progress of a viral URTI
Rhinovirus, RSV, Coronaviruses, influenza,
- Fever 1-3 days from the onset of infection
- Cough, runny nose, sore throat for from 1-12 days, peaking day 3-6.
- Rhinorrhoea progresses from clear to purulent to clear over 1-2 weeks.
When should a sore throat be treated with antibiotics and how
Treated with antibiotics to avoid risk of developing rheumatic fever
- Maori/ Pacific population
- School age children
- History of rheumatic fever in the family
If Strep Pyogenes is cultured from throat swab then it is important to treat with oral penicillin/ erythromycin. If low risk (eg. middle age caucasian woman) then even if GAS present don’t treat - infection will clear 7-10 days.
How does Rhinosinusitis present, compare % the different viral and bacterial causes and how this can be confirmed
Presents with purulent nasal discharge, nasal congestion/fullness, fever, facial pain or pressure, reduced smell.
90-98%: Viral: rhinovirus, influenza, para-influenza
2-10%: Strep pneumonie, Haemophilus influenzae
This can be confirmed with sinus aspiration
How are Rhinoviruses transmitted, where do they infect, how does this present, how is it treated and the time course
- Transmitted by respiratory droplets/contaminated surfaces
- incubates for 1-4 days. Infects the nose and sinuses.
- Nasal mucous, sneezing, cough, sore throat, minor fever, muscle ache. - Recovery in 1-2 weeks. Symptomatic treatment only as no effective antiviral or vaccine. Recovery with long lasting immunity to the serotype.
