Fever in children — KFP-style written assessment

KFP 1 (10 marks)

A 5-week-old boy is brought in by his mother, who reports he "felt hot" overnight. Your axillary electronic thermometer reads 38.1°C. He fed at 6 a.m., is alert, and smiles at you. He has mild nasal congestion; the chest is clear; ears are normal. ^[38]

1. Classify his risk using NICE NG143 and state the mandatory investigation panel. (4) ^[38]
2. Which additional findings would mandate lumbar puncture in this age band, and when should antibiotics be given? (4) ^[38]
3. The mother asks whether paracetamol will "bring the fever down and stop it getting worse". Answer her precisely. (2) ^{[38] [36]}

Model answers

1. He is high-risk automatically: any infant younger than 3 months with a temperature of 38°C or higher is in the high-risk group for serious illness regardless of appearance — his alert, smiling behaviour does not lower the tier. The mandatory panel is full blood count, blood culture, C-reactive protein and urine testing for urinary tract infection; chest X-ray only if respiratory signs appear (his chest is clear, so none needed); stool culture only if diarrhoea is present. He requires urgent specialist assessment — this is a hospital pathway, not a home-management pathway. ^[38]
2. Lumbar puncture is performed (unless contraindicated) in all infants younger than 1 month — he qualifies on age alone; in all infants aged 1–3 months who appear unwell; and in infants aged 1–3 months with a white cell count below 5 × 10⁹/L or above 15 × 10⁹/L. It should be performed without delay and, whenever possible, before antibiotics. Parenteral antibiotics are indicated for infants under 1 month with fever and for 1–3-month-olds who appear unwell or meet the WCC thresholds; the regimen is a third-generation cephalosporin (cefotaxime or ceftriaxone) plus listeria cover (ampicillin or amoxicillin). ^[38]
3. Antipyretics relieve distress; they do not treat the illness and do not prevent deterioration. Use paracetamol 15 mg/kg per dose every 4–6 hours (maximum 4 doses in 24 hours) only if he appears distressed, never with the sole aim of reducing temperature, and never to prevent convulsions. The dose should be based on weight, and his fever here is an investigation trigger, not a number to suppress. ^{[38] [36]}