Fever in children

The most common ailment of childhood is feverish illness. In England and Wales, for example, general practitioners are consulted by their paediatric patients for feverish illnesses on average 3.7 times a year.^{1 2} Fortunately, most feverish illnesses are caused by self limiting, harmless viral infections. Set against this benign backdrop are sinister bacterial infections, such as meningitis, which, if left untreated, may have fatal consequences.

The challenge of managing children with feverish illnesses is to identify those children at risk of serious illness while avoiding unnecessary treatment and investigation of children with benign viral illnesses. Junior staff in general practice, emergency departments, and paediatric departments are on the front line.

Differential diagnoses

Viral infections—Most feverish illnesses are caused by respiratory and gastrointestinal viruses. Both can cause malaise and often erythematous rashes, which are usually blanching. Although mostly benign and self limiting, viruses may occasionally cause serious, life threatening illnesses—for example, respiratory failure in bronchiolitis.

Bacterial infections—Bacterial infections can present with focal symptoms produced by the affected organ—for example, ear pain in bacterial otitis media—with non-specific symptoms akin to viral illnesses, or with misleading symptoms—for example, vomiting, but no urinary symptoms, in urinary tract infections. Common sites for bacterial infections in children are the lower respiratory and urinary tracts. The most feared complication of bacterial infections is sepsis, a systemic non-specific inflammatory response associated with evidence, or suspicion, of a microbial origin, which can cause death within hours. You must presume that children who present with a feverish illness have a life threatening bacterial infection until convinced otherwise by a thorough assessment.

Rare causes—Rarely is feverish illness in a child caused by one of the diseases in box 1. Note that teething is not included in the list because, despite myth, teething does not cause fever.³

Assessment

The key to successful management of a child with feverish illness is a systematic assessment based on a detailed history (see box 2 and box 3) and a full examination of the child from top to toe (including ears, throat, skin, peripheral perfusion), supplemented occasionally by investigations (see box 4). Anitpyretics are useful in providing analgesia and reducing fever, thus making assessment easier as all children will be irritable and tachycardic when in pain or feverish. However, the speed at which the temperature resolves after antipyretics is a poor indicator as to the severity of the underlying cause. Similarly the height of temperature is not a specific indication of viral or bacterial infection. It should also be noted that antipyretics do not reduce the risk of febrile convulsion. The aim of the assessment is to answer the following questions:

Is this a sick child who needs immediate resuscitation?

Careful observation of the child, as previously discussed in the Student BMJ,⁴ and assessment of vital signs according to the universal airway, breathing, circulation (ABC) algorithm shows whether the child needs immediate resuscitation. In addition, look out for the features summarised in box 4, which indicate that a child is sick.

Children are physiologically different from adults. They compensate very well in the face of acute illness but these compensatory mechanisms reach their limits quickly and often with little warning. For example, hypotension in a sick child indicates a substantial risk of impending cardiorespiratory arrest. The heart rate is a particularly important vital sign because it indicates an increased cardiac output, which in children is achieved predominantly by increasing heart rate rather than stroke volume.

What are the parents worried about?

It is important early in the assessment to establish parental concerns and the parents’ lay diagnosis of their child’s illness. If parents think that their child is sick they are usually right, and their concerns need to be listened to carefully.

Is there a focus of infection?

Try to find a focus of infection by asking relevant questions and by looking for clues in the clinical examination as outlined in box 3. A potential pitfall of finding a focus of infection is that it may provide false reassurance. For example, coryzal symptoms and signs are common in children and may coexist with serious bacterial infections.

Is there a rash?

A common reason for parents to seek medical advice about their child’s feverish illness is the presence of a rash. It is of utmost importance to inspect the entire body carefully for the presence of a rash. It may be challenging to see rashes in dark skinned children and in poorly lit rooms. If you find a rash determine whether it is blanching or non-blanching and show your findings to the parents.

Assume until proved otherwise that a child with a feverish illness and a non-blanching rash has meningococcal septicaemia—that is, sepsis caused by Neisseria meningitidis. This is a medical emergency that needs immediate treatment—that is, resuscitation and parenteral antibiotics—and the involvement of senior paediatricians.⁵ Out of hospital give intramuscular antibiotics before transfer of the child to hospital—for example, intramuscular benzylpenicillin if the child is not allergic to penicillin. Blanching rashes are usually benign and often accompany viral illnesses. The presence of a blanching rash does not exclude a life threatening bacterial infection. It is important to remember that the early rash of meningococcal septicaemia may be blanching.⁵

Are any investigations required?

Even when a focus of infection is suspected, investigations may be necessary to confirm the diagnosis. For example, a urinary tract infection in children must be confirmed by a positive urine culture. If no focus of infection is found a variety of tests, known as a septic screen, may help (box 5).

The child’s risk of having a serious illness must be assessed and the tests to include in a septic screen should be decided accordingly.^{1 2} This risk can be determined using the criteria outlined in the table. The greater the risk of serious illness, the more investigations should be included in the septic screen (a detailed algorithm is outlined in references 1¹ and 2²). Children in the red category are usually easy to recognise. They require prompt treatment as inpatients and usually further investigations. Children in the green category are generally well, albeit febrile children. However, even these children will require a urine dipstick test (and urgent microscopy in infants) and urine culture when there is no apparent focus of infection. Children in the amber category may occasionally be difficult to distinguish from children in the green category; a pair of senior eyes will help in these situations. Note that young, febrile infants (defined in the guideline as younger than 3 months old), with or without a focus of infection, will be investigated and treated more aggressively, usually as inpatients, under guidance of paediatricians.

Does this child require inpatient treatment?

Indications for inpatient treatment are given in box 6. Findings of the assessment should be documented succinctly (in legible writing) including the most likely diagnosis (and differential diagnoses) followed by a problem list and a management plan.

Management

The management of a child with a feverish illness depends on the underlying diagnosis and how sick the child is. If you have any doubts about either, err on the side of caution and ask a senior colleague or a paediatrician to review the child. The management plan should consider the following points—inpatient or outpatient treatment; need for antibiotics and most appropriate route; fluid requirements and monitoring urine output; need for other supportive measures, for example, oxygen therapy; antipyretics, ibuprofen; paracetamol; monitoring of vital signs; parental concerns; and follow-up arrangements. Occasionally, very sick children need intensive care, as judged by an experienced paediatrician.

Explanation of the management to parents and discussion with them at every stage of the child’s illness is crucial. Sometimes children who seem well at the time of assessment in hospital deteriorate at home, in which case the parents should return to the hospital at once. Provide parents with a safety net by informing them about signs of critical illness in children, ideally in conjunction with written information. At times it may be necessary to arrange a formal review of the child either face to face or by phone.

Parents and doctors often encounter and struggle with feverish illness in children, which is common and mostly benign. Basing your management on a thorough assessment will enable you to recognise sick children. Most importantly, do not hesitate to ask senior colleagues for help. Finally, our tips in box 7 will help you to avoid common mistakes.

Competing interests: none declared.

Provenance and peer review: Not commissioned; externally peer reviewed.

See “Intuition and the ill infant” (Student BMJ 2001;9:98-100, http://student.bmj.com/issues/01/04/education/98.php).

1. National Institute for Health and Clinical Excellence. Feverish illness in children: assessment and initial management in children younger than 5 years. London: NICE, 2007. www.nice.org.uk/GG047
2. National Collaborating Centre for Women’s and Children’s Health. Feverish illness in children: assessment and initial management in children younger than 5 years. London: Royal College of Obstetricians and Gynaecologists Press, 2007.
3. Wake M, Hesketh K, Lucas J. Teething and tooth eruption in infants: a cohort study. Pediatrics 2000;106:1374-9.
4. Gill D. Intuition and the ill infant. Student BMJ 2001;9:85-128
5. Ninis N, Nadel S, Glennie L. Lessons from research for doctors in training: recognition and early management of meningococcal disease in children and young people. 2nd ed. London: Meningitis Research Foundation, 2007.

       

 Printable version      Download PDF    E-mail this to a friend    Respond to this article    Request Permissions