Cough Flashcards
What are the causes of cough
Viral induced wheeze
Infective exacerbation of asthma
Bronchiolitis
Pneumonia
URTI: common cold, pharyngitis, otitis media, croup
What causes whooping cough
Bordetella pertussis → pertussis toxin
It is transmitted by aerosol droplets released during coughing
Infectious from onset of symptoms until 48 hors of appropriate antibiotic treatment OR 21 days from onset of symptoms
Incubation period of is 7-10 days
A previously infected person can become re-infected, but the subsequent infections are usually less severe
What are the symptoms of whooping cough
3 phases:
1. Catarrhal phase (1-2 weeks)
- nasal discharge, conjunctivitis, malaise, sore throat, fever, dry unproductive cough
2. Paroxysmal phase (1-6 weeks)
- Paroxysms/cough: severe dry cough
- May vomit/be apnoeic after/between
- More common at night
- May be productive: thick mucous plug/watery secretion
- Inspiratory ‘whoop’ heard
- Otherwise well, sleep undisturbed
3. Convalescent phase (up to 3 months)
- Gradual improvement in cough frequency and severity
What are the differentials for whooping cough
Mycoplasma infection
Chlamydia pneumoniae/trachomatis
Adenoviruses
Bronchiolitis
Asthma
URTI
GORD
What are the signs of whooping cough on examination
No crackles/crepitations and no wheeze
What investigations should be done for whooping cough
bedside: nasopharyngeal swab/aspirate for PCR and culture
Bloods: anti-pertussis toxin IgG serology
What is the criteria for whooping cough diagnosis
Clinical features with:
1. Bordetella pertussis isolated from a nasopharyngeal aspirate or nasopharyngeal/pernasal swab, or
2. Detection by real-time PCR of the pertussis toxin S1 promoter region (ptxA-pr), and the insertion element IS481, or
3. Anti-pertussis toxin IgG detected in serum or oral fluid in the absence of vaccination within the past year.
What is the management for whooping cough
Notify local public health england (PHE) centre within 3 days (notifiable disease)
First line: Abx
- <1 month: clarithromycin
- >1 month: azithromycin
+ advice
- Rest
- Adequate fluid intake
- Paracetamol/ibuprofen
- Even with treatment there may be a non-infectious cough
- Isolate until 48h of abx treatment OR 21 days after symptoms started
- Contacts may require prophylaxis
Who requires prophylaxis for whooping cough
Premature (<32w) unimmunised infants <2 months of age
Unimmunised infants (>32w birth) <2 months of age, no maternal pertussis vaccine
unimmunised/partially unimmunised >2 months
Pregnant women >32w
Healthcare workers working with infants and children
Those who share a household with infants too young to be fully vaccinated
Describe the whooping cough vaccine
Reduces risk of developing pertussis, does NOT provide absolute protection
Protection level declines during childhood
Immunisation of mothers in pregnancy → reduces risk of pertussis of the infant in the first few months
Offered at 16-32 weeks
What are the complications of whooping cough
Post-infectious cough: May last for 3 months or more - “the one hundred day cough”
Apnoea
Pneumonia
Seizures
Encephalopathy
Otitis media
Unilateral hearing loss
Bronchiectasis
Increased intra-thoracic and intra-abdominal pressure: pneumothorax, umbilical and inguinal hernia, rectal prolapse, rib fracture, herniation of lumbar intervertebral discs, urinary incontinence, subconjunctival or scleral haemorrhage
Frequent post-tussive vomiting can lead to severe dehydration and/or malnutrition.
What is the prognosis for whooping cough
For people who have not previously contracted whooping cough AND are not vaccinated: may be left with a protracted cough that can last 3 months or more
Previous vaccination or infection: short-lived, mild symptoms and an isolated persistent cough
Mortality rate in children <6 months is 3.5%
