Approach to fever by age and immune status — OSCE

Station brief (candidate)

• Explain why age drives the work-up threshold in febrile infants.
• Outline the assessment: threat gate first, then age-banded risk stratification.
• State which investigations a 5-week-old fever without source requires and why.
• Agree a plan that respects parental concern and gives a specific safety-net.
• Avoid reassuring on temperature alone or promising discharge before assessment. [1] [2] [6]

Role-player notes

You are a worried first-time parent. Your 5-week-old has had fever for six hours, has fed less, and you feel the baby is "not right." You become anxious and frustrated if the doctor dismisses the temperature as low or says "probably viral" before examining the baby. You cooperate well when the doctor explains the age-based reasoning, takes your concern seriously, and outlines a clear plan. [5]

Expected candidate performance

1. Opening: "Fever in a young infant needs careful assessment because the risk of serious infection is higher than in older children. I will examine your baby first, then decide what tests are needed based on their age and how they look." [1]
2. Threat gate: Examine appearance, work of breathing, perfusion, and interaction. If any toxic feature is present, escalate to the emergency sepsis pathway. [1]
3. Age-banded reasoning: A 5-week-old (29–60 days) is risk-stratified with a validated rule such as Step-by-Step or the PECARN rule. Explain that this guides whether a lumbar puncture and admission are needed. [2] [3]
4. Fever-height trap: Acknowledge that the temperature number alone does not tell us whether the infection is serious; behaviour and the validated rule do. [4]
5. Safety-net: Give a written, specific safety-net — return immediately for reduced interaction, breathing difficulty, poor perfusion, persistent fever, rash, or if the parent feels the baby is worse. [6]
6. Communication: Validate the parent's concern as useful data, use teach-back to confirm understanding, and arrange interpreter if needed. [5]

Marking domains

• Age-based reasoning that names why a 5-week-old is higher-risk than an older child.
• Threat gate applied before reassurance.
• Awareness of validated febrile-infant rules without inventing cut-offs.
• Specific, written safety-net.
• Respectful, concern-validating communication. [2] [5] [6]

Common fails

• "The temperature is only 38, so it is probably viral."
• Promising discharge before examining the baby.
• No mention of a validated risk-stratification rule for the 29–60-day group.
• Dismissing parental concern.
• No written safety-net or return criteria. [4] [5]