Which red flag symptoms in an adult with fever should prompt immediate referral to secondary care?

Red flag symptoms in an adult with fever that should prompt immediate referral to secondary care include:

• Fever accompanied by neck stiffness, headache, and altered level of consciousness or cognition (including confusion or delirium), which strongly suggests bacterial meningitis and requires emergency hospital transfer.
• Presence of a non-blanching petechial or purpuric rash, which may indicate meningococcal disease and necessitates urgent referral.
• Signs of severe illness such as pale, mottled skin or cyanosis, which may be difficult to detect on darker skin but indicate critical illness.
• Unexplained fever with splenomegaly, which may suggest non-Hodgkin's lymphoma and warrants a suspected cancer pathway referral.
• Fever with unexplained lymphadenopathy, especially if persistent or associated with other systemic symptoms, which may indicate lymphoma or leukemia and requires urgent specialist assessment.
• Fever with persistent unexplained symptoms such as fatigue, weight loss, or night sweats, which may indicate serious underlying conditions including cancer and should prompt urgent investigation.

Any adult presenting with these red flag symptoms alongside fever should be referred immediately to secondary care for urgent assessment and management.

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