What are the key red flags to look for in a patient with URTI that may indicate a more serious underlying condition?

Key red flags in a patient with an upper respiratory tract infection indicating a more serious underlying condition include:

• High fever, especially if persistent or accompanied by headache, neck stiffness, or altered consciousness, which may suggest bacterial meningitis NICE NG240.
• Non-blanching petechial or purpuric rash, which is a sign of meningococcal disease NICE NG240.
• Severe breathlessness or oxygen saturation below 90% on room air, indicating possible pneumonia or severe lower respiratory tract infection NICE CG191.
• Respiratory rate ≥24 breaths per minute, heart rate >100 beats per minute, systolic blood pressure ≤90 mmHg, or abnormal mental status, all of which suggest severe illness such as pneumonia NICE CG191.
• Persistent or recurrent chest infections, especially in patients aged 40 and over, which may indicate underlying lung cancer and warrant urgent chest X-ray NICE NG12.
• Unexplained weight loss, fatigue, or appetite loss in conjunction with respiratory symptoms, raising suspicion of malignancy NICE NG12.
• Persistent unexplained hoarseness in patients aged 45 and over, which may indicate laryngeal cancer NICE NG12.
• Signs of poor feeding, lethargy, irritability, or unusual behaviour in children, which may indicate serious infection NICE NG240.

These red flags should prompt urgent clinical assessment and consideration of hospital referral or further investigations to exclude serious conditions such as bacterial meningitis, pneumonia, or cancer NICE NG240,NICE NG12,NICE CG191.