Upper Respiratory Infections Flashcards
Definition of Rhinitis
Sneezing attacks,
Nasal discharge,
or
blockage of the nose
for more than an hour on most days.
Explain the common cold.
A form of rhinitis also called acute coryza.
It is caused by a variety of respiratory viruses such as rhinoviruses, coronaviruses and adenoviruses.
Clinical features of common cold.
Tiredness
Slight pyrexia
Malaise
Sore nose
Sore pharynx
Sneezing and profuse watery nasal discharge followed by thick mucopurulen secretions that may persist for up to a week.
Other forms of rhinitis can be subdivided into what?
By frequency with which symptoms occur;
For a limited period of the year called seasonal or intermittent rhinitis
Throughout the whole year called perennial or persistent rhinitis
Explain seasonal intermittent rhinitis.
Most common allergic disorder also called hay-fever.
However hayfever implies that only grass pollen is responsible, making a better descriptatory term to be seasonal or intermittent allergic rhinitis.
Common allergens causing seasonal rhinitis.
Tree and grass pollens and mould spores.
Clinical features of season rhinitis.
Nasal irritation
Sneezing
Watery rhinorrhoea
Itching of the eyes and soft palate and occasionally ears.
Clinical features of perennial rhinitis.
About 50% have symptoms of sneezing and watery rhinorrhoea.
Other 50% usually only report nasal blockage.
Patients may lose senses of smell and taste but rarely eye or throat symptoms.
Sinusitis may occur in about 50% due to mucosal swelling that obstructs the drainage from the sinuses.
Most common cause of perennial allergic rhinitis.
Allergy to the faceal particles of the house-dust mite.
They are usually found in human bedding.
The second most common cause are allergens from domestic pets especially cats.
Can also be allergy to urinary protein from small mammals.
Industrial dust, vapours and fumes can also cause it.
Complications of perennial allergic rhinitis.
It makes the nose more reactive to non-specific stimule such as cigarette smoke, washing powders, househould detergents, strong perfumes and traffic fumes.
Explain perennial non-allergi rhinitis with eosinophilia.
When no extrinsic allergic cause can be identified - neither on history nor testing of the skin.
However eosinophilic granulocytes can be found in nasal secretions.
Explain vasomotor rhinitis.
No demonstrable allergy or nasal eosinophilia.
However they still respond with watery secretions and nasal congestions to cold air, smoke, perfume or newsprint.
It is thought to be because of an imbalance of the autonomic nerves controlling the erectile tissue in the nasal mucosa.
Explain nasal polyps.
Round, smooth, soft, semitranslucent, pale or yellow glistening structures attached to the sinus mucosa.
Occurs in patients with allergic or vasomotor rhinitis.
Can cause nasal obstruction, loss of smell and taste.
Rarely any sneezing.
Investigations and diagnosis of rhinitis.
Allergic factors causing rhinitis by history and skin-prick testing to support the history.
Allergen-specific IgE antibodies can be done if skin-prick test cannot be performed.
Management of rhinitis.
If allergic then removal of household pets, occupational allergen etc… will cure it.
Pollen avoidance is impossible.
Antihistamines such as loratadine, cetirizine and fexofenadine relieves sneezing and itching of eyes.
Decongestants such as alpha-adrenergic agents.
Anti-inflammatory drugs such as sodium cromoglicate and nedocromil sodium.
Corticosteroids along with anti-histamine is the best combination and should be started before the beginning of seasonal symptoms.
Montelukast is an alternative
Most common viruses in pharyngitis.
Adenoviruses
Endemic adenovirus infection causes the common sore thorat in which the oropharynx and soft palate are reddened and the tonsils are inflamed and swollen.
This is usually a self-limiting condition.
Two forms of influenza.
A and B
Differences between influenza A and B.
B is associated with localised outbreaks of mild disease
A causes worldwide pandemics.
Incubation period of influenza.
1-3 days
Clinical features of influenza.
Fever
Shivering
Generalised aching
Severe headache
Soreness of throat
Dry cough that can persist for weeks
Complications of influenza.
Secondary bacterial infection such as S. pneumoniae, H. influenzae and more rarely S. aureus.
Post-infectious encephalomyelitis is rare after influenza infection.
Diagnosis of inluenza.
Laboratory is usually not necessary.
Definitive diagnosis can be made by four-fold increase in complement fixing antibody or haemagglutinin antibody or by taking nasopharyngeal swabs.
It is however usually just done by history.
Management of influenza.
Bed rest and paracetamol.
Antibiotics is given to chronic bronchitis or cardiac or renal disease to prevent secondary infection.
Neuraminidase inhibitors can be given to help shorten the duration of symptoms.
Vaccines.
