Does febrile neutropenia cause unexplained fever?

Neutropenia means the body has fewer neutrophils, white blood cells that help fight infection. When neutrophil levels are low, an infection may develop without a clear local symptom. Fever can be the first or only sign, and the cause may remain unidentified even after initial tests.

Febrile neutropenia is treated as urgent because infection can worsen quickly when immune defences are reduced. Chills, weakness, confusion, breathlessness, cough, pain, diarrhoea, burning urine, or redness around a wound may occur, but their absence does not make fever safe to ignore.

If you are receiving cancer treatment and develop a fever or feel suddenly unwell, follow the emergency instructions from your oncology team and contact them immediately. Check your temperature with a reliable thermometer if this does not delay the call. Tell the team your treatment dates, current medicines, and any central line or other device.

Do not take fever-reducing medicine to mask the symptom unless your clinical team has advised it. Do not wait for the fever to settle or attend an appointment later without first reporting it. The team may arrange blood tests, cultures, examination, and treatment based on your risk.

Seek emergency care for fever with confusion, fainting, severe weakness, difficulty breathing, chest pain, shaking chills, or inability to keep fluids down. Urgent review is also needed for a new fever during chemotherapy, immunotherapy, stem-cell treatment, or other treatment known to lower white blood cells.

What temperature or symptoms should trigger an emergency call? Which number should I use outside clinic hours? How long might my neutrophil count remain low? Which medicines should I avoid before assessment?