- Most febrile children have a brief, self-limiting viral infection. Mild localised infections, e.g. otitis media or
tonsillitis, may be diagnosed clinically. The clinical problem lies in identifying the relatively few children
with a serious infection which needs prompt treatment - (i) How is fever identified in children?
Parents usually know if their child has been febrile. In hospital, it is measured at:
• <4 weeks old by an electronic thermometer in the axilla
• 4 weeks to 5 years by an electronic or chemical dot thermometer in the axilla or infrared tympanic
thermometer.
In general, axillary temperatures underestimate body temperature by 0.5°C - (ii) How old is the child?
Febrile infants <3 months old present with non-specific clinical features (see Box 10.2) and often have a bacterial infection, which cannot be identified reliably on clinical examination alone. It is uncommon for them to have the common viral infections of older infants and children because of passive immunity from their
mothers - iii) Are there risk factors for infection?
These include:
• Illness of other family members
• If a specific illness is prevalent in the community
• Unimmunised
• Recent travelabroad, e.g. malaria, typhoid• Contact with animals, e.g. brucellosis.
• Increased susceptibility from immunodeficiency. This is usually secondary, e.g. post-autosplenectomy in sickle cell disease or splenectomy or nephrotic syndrome, resulting in increased susceptibility to encapsulated organisms (Streptococcus pneumoniae, Haemophilus influenzae and salmonella), or rarely, primary immune deficiency. - (iv) How ill is the child?
Red Flag features suggesting serious illness and the need for urgent investigation and treatment are:
• Fever >38°C if <3 months, >39°C if 3–6 months
• Colour – pale, mottled, blue
• Level of consciousness is reduced, neck stiffness, bulging fontanelle, status epilepticus, focal neurological signs or seizures
• Significant respiratory distress
• Bile-stained vomiting
• Severe dehydration or shock - (v) Is there a rash?
Rashes often accompany febrile illnesses. In some, the characteristics of the rash and other clinical features
lead to a diagnosis, e.g. meningococcal septicaemia; in many, a specific diagnosis cannot be made clinically. - (vi) Is there a focus for infection?
Examination may identify a focus of infection (Fig. 14.3). If identified, investigations and management will
be directed towards its treatment. However, if no focus is identified, this is often because it is the prodromal
phase of a viral illness, but may indicate serious bacterial infection, especially urinary tract infection or
septicaemia.