Paediatric Pearls

More background to pertussis with thanks to Dr Rupa Vora

• whooping cough is caused by Bordetella pertussis, a gram negative pleomorphic bacillus. It is spread by aerosol transmission and the bacteria cause damage by attaching to the respiratory cilia
• it occurs in clusters every 2-5 years during the summer months. We currently have an outbreak with the HPA provisionally reporting 665 cases in the first quarter of 2012 (cf. 1040 cases in 2011, 421 in 2010)
• cases have dropped dramatically since pertussis vaccinations have been introduced. Acellular pertussis vaccination is given at 2 and 3 months, followed by a pre-school booster.  However, protection wanes quickly and has virtually disappeared by 12 years old
• incubation period is 3-12 days and children are most infectious in the first 2-3 weeks. They are most likely to present in the second phase of illness at 3-4 weeks
• can present with coryza (1^st stage which lasts a couple of weeks), paroxysms of cough, difficulty feeding and pneumonia. Younger infants (<6months) may not present with the characteristic ‘whoop’. Older children and adults often present with a persistent cough
• complications include chronic cough (“100 day cough”), hypoglycaemia, seizures, encephalopathy and intracranial haemorrhage
• any infant is vulnerable and up to 50% may need hospitalisation.  Especially vulnerable are ex-prems and those with underlying cardiology, respiratory or neurological problems.  
• In England and Wales, whooping cough is statutorily notifiable.  The diagnosis is usually made on clinical grounds without the requirement for laboratory confirmation
• The UK Health Protection Agency advises a 7 day course of erythromycin or clarithromycin (or azithromycin for 3-5 days if under 4 weeks) to reduce spread.  A pernasal swab to confirm or refute B. pertussis as the causative organism can be carried out.  If the cough has been present for more than two weeks and the child is in the community, serum serology can be sent to Colindale.  See table below:

Appropriate laboratory tests for a sporadic case of pertussis reported to HPA on clinical suspicion (with thanks to Dr Maria O’Callaghan): 

 NPA – nasopharyngeal aspirate; PNS – pernasal swab;

RSIL – Respiratory and Systemic Infections Laboratory, Colindale

Useful websites:

HPA: www.hpa.org.uk/Topics/InfectiousDiseases/InfectionsAZ/WhoopingCough/

NHS Choices: www.nhs.uk/Conditions/Whooping-cough/Pages/Introduction.aspx

Children from about 5 years old may be able to use a Peak Flow Meter to record their PEFR. As one of the parameters by which we diagnose a severe or life-threatening asthma exacerbation is the percentage drop in PEFR, it would help to know what a child’s normal PEFR is! Click here for a guide of what you might expect for height. Children don’t always conform to these norms so it is important to know what the child’s own normal PEFR is; a 20% drop in their norm suggests poor control of asthma, a 40% drop suggests a significant exacerbation.

Most families in the Emergency Department will talk about their child’s “blue” and “brown” inhaler.  Can we, or they, tell which is the reliever and which the preventer? 

 Click here for a printable table of some common inhalers listed by colour.  I have also found a very useful site put together by a pharmacist and a medical student with photos of lots of the inhalers so you can get your patient to identify which one they are on.  Take a look at http://www.rch.org.au/clinicalguide/asthmadevices/

http://www.asthma.org.uk/health_professionals/materials_to_help_you_your_patients/index.html has a link to a comprehensive information leaflet for young people over the age of 12 who need to take control of their asthma management and understand their condition.

http://www.nice.org.uk/nicemedia/live/11400/32073/32073.pdf  is the 2000 guideline on asthma management in the < 5 year olds

http://www.nice.org.uk/guidance/index.jsp?action=byID&r=true&o=11450 is the 2002 guideline for 5-15 year olds

With thanks to Amutha for this article….

As winter approaches, most of us are very well aware that the bronchiolitis season is in full swing. Bronchiolitis is a lower respiratory tract infection – in the under 1s predominantly – that can cause fever, dry cough, nasal discharge and bilateral fine inspiratory creps ± wheeze.  Most cases of bronchiolitis occur from November to March, when the viruses that can cause bronchiolitis are more common. It is also possible to get bronchiolitis more than once during the same winter season (1).

Treatment is largely supportive and many infants are managed at home if they are feeding adequately and do not have significant respiratory difficulty.  Patients at high risk are ex-premature babies, those with congenital cardiac or respiratory diseases, immunodeficiency and babies < 3months of age (2).  When seeing a child, we should focus our history and examination on risk factors, signs of dehydration and respiratory distress.  This podcast provides an example of respiratory distress:

 http://empem.org/2010/09/bronchiolitis-part-1-of-2/comment-page-1/#comment-294

 3% of children will present with severe illness and require admission (2).  Map of Medicine (http://healthguides.mapofmedicine.com/choices/map/bronchiolitis1.html)  defines “severe” as those with:

• poor feeding – less than half normal intake
• lethargy
• history of apnoea
• respiratory rate above 70breaths/minute
• presence of nasal flare and/or grunting
• severe chest wall recession
• cyanosis
• marked use of accessory muscles
• marked intercostal and subcostal recession
• oxygen saturation (SaO₂) 94% or less

 There have been no therapies that have been consistently effective enough to change the current supportive management of bronchiolitis. The majority of trials show that bronchodilators do not provide benefit and their routine use is not recommended (3). 

 1.http://www.nhs.uk/conditions/Bronchiolitis/Pages/Introduction.aspx

 2. Scottish Intercollegiate Guidelines Network (SIGN). Bronchiolitis in children. A national clinical guideline. Edinburgh: SIGN; 2006. http://www.sign.ac.uk/pdf/sign91.pdf

3. Petruzella FD, Gorelick MH. Current therapies in bronchiolitis. Pediatr Emerg Care 2010 Apr;26(4):302-7