OVERVIEW OF UPPER RESPIRATORY TRACT INFECTIONS(URTIs) Flashcards
Common cold(Rhinitis)
cause?
Most are caused by viruses(mostly rhinoviruses, coronaviruses, occasionally respiratory synctial viruses, human metapneumoviruses)
Rhinitis
MOTransmission
Mode of transmission: droplets and direct contact
Rhinitis
Pathogenesis?
Pathogenesis: depending on the virus, destruction of epithelial lining with associated acute inflammatory response
Release of inflammatory cytokines and infiltration of the mucosa by inflammatory cells
rhinitis
Incubation period?
Incubation period -48-72hrs
Rhinitis
Clinical features?
Clinical features- 1st symptom- sore/scratchy throat, then nasal discharge and obstruction
Others – cough(30%), fever (rare)
Nasal cavity examination- swollen and erythematous nasal turbinates
Usually persists for 1 week
Rhinitis
Diagnosis ?
Diagnosis – clinical
Laboratory work up- nasal smear- eosinophils ( allergic rhinitis), polymorphonuclear cells (uncomplicated colds)
Viral culture, Polymerase chain reaction, serologic methods
Bacteria culture( group A streptococcus etc)
Rhinitis
Differential diagnosis ?
Differential diagnosis
-Allergic rhinitis- prominent itching and sneezing
-Foreign body- bloody nasal secretions, foul smelling discharge
-Sinusitis- fever, headache, facial pain, periorbital oedema, persistence of rhinorrhoea or cough for > 14 days
rhinitis
Management?
Management- majorly symptomatic, the use of most drugs involved is controversial in children
-Nasal decongestants- xylometazoline, phenylephrine
First generation anti-histamines- chlorpheniramine
Topical anticholinergic- ipratropium bromide
Antipyretic- acetaminophen, because of the risk of Reye syndrome, aspirin should be avoided
Plenty of fluids and bed rest
Rhinitis
Complications?
Complications
Otitis media-
Sinusitis
Exacerbation of asthma
Rhinitis
Prevention?
Prevention
Good hand washing
Restriction of activities to avoid infecting others
Sinusitis(Rhinosinusitis)
Aetiology?
Aetiology- viruses, bacteria and fungi
Commonly implicated microorganisms- bacteria(streptococcus pneumoniae(30%) Haemophilus influenzae(20%), Moraxella catarrhalis(20%).
Sinusitis
Pathogenesis?
Pathogenesis - congestion and blockage of the nasal passages usually in response to viral infection or allergic rhinitis.
mucus cannot drain properly, providing an environment where bacteria or fungus can thrive.
NB; Persons with chronic nasal congestion, and particularly those with allergies and asthma may be more prone to developing acute sinusitis
Sinusitis
Clinical features?
Clinical features- non specific-
- Features of rhinitis lasting more than 10 to 14 days
- Fever
Thick yellow-green nasal drainage for at least three days in a row
sore throat, cough, nausea and/or vomiting
- Headache, usually in children age six or older
- Irritability or fatigue
- less commonly halithosis, decrease sense of smell and periorbital oedema
Sinusitis
Physical examination & Transillumination ?
Physical examination- erythema and swelling of the nasal mucosa, purulent nasal discharge
Transillumination- opaque sinus that transmits light poorly
Sinusitis
Diagnosis ?
Diagnosis- clinical
Sinus puncture and imaging - When treatment is ineffective and sinusitis persists, when symptoms are severe or suspicion of fungal sinusitis.
Sinusitis
Differential diagnosis ?
Differential diagnosis – Allergic rhinitis and nasal foreign body