Prolonged Fever

This section refers to the child with fever that is persistent or recurrent for longer than 7 days without an apparent cause.

Guidance on the approach to prolonged fever is available.

Key points to consider are:

• Careful clinical assessment to exclude red flags (suggestive of malignancy or infection), foreign travel, history of tick bites and health of family members, pets and their health, medication history, sexual history.
• Careful examination should include looking for rashes (especially when febrile), lymphadenopathy, mouth ulcers, evidence of heart murmurs or nail fold changes (endocarditis), joints and fundoscopy. 
• 'First line' investigations aim to exclude infection and autoimmune disease and usually includes: Blood cultures when febrile, urine microscopy and culture, autoantibodies, chest radiograph, cerebrospinal fluid analysis.
• Always consider Kawasaki disease and in particular younger age children (< 5 years).
• In the immunosuppressed child (either due to underlying disease or treatment), always consider Tuberculosis and unusual / opportunistic infections.
• Further investigation is dependent on the clinical context and includes: Abdominal Ultrasound / MRI / CT / Angiography and bone marrow (to help exclude malignancy and infections).
• If fever is lasting more than 7 days and is of a quotidian pattern (i.e., high in the evenings) then systemic JIA is more likely.  It is important to check for rash especially in the evenings when the fever is high - the rash may be more on the inner thighs, axillae, inner arms or trunk so it is important to expose the child as appropriate. 

Conditions to consider in the differential diagnosis below and vary with the clinical context and geographical location in the world. The conditions in bold are covered in more detail in other modules.

Infections:

• Abscess.
• Endocarditis .
• Septic arthritis / osteomyelitis.
• Sinusitis.
• Mycobacterial disease (Tuberculosis).
• Human Immunodeficiency Virus (HIV) disease. 
• Brucellosis.
• Malaria.
• Chikungunya. 
• Enteric fever.
• Lyme disease.
• Dengue Fever.
• Acute Rheumatic fever.
• Urinary tract infection.
• Infectious mononucleosis.
• Mycoplasma infection.
• Leptospirosis.
• Rickettsial diseases.

Malignancy:

• Leukaemia.
• Neuroblastoma.
• Lymphoma .

Multisystem Auto-immune / Autoinflammatory disease:

• Systemic Juvenile Idiopathic Arthritis (JIA).
• Vasculitis - Kawasaki, Polyarteritis nodosa, Takayasu arteritis.
• Juvenile Systemic Lupus Erythematosus (JSLE).
• Autoinflammatory syndromes.

Further Information:

Periodic syndromes and the spectrum of autoinflammatory disease.

Prevention, Diagnosis and Management of Acute Rheumatic Fever and Rheumatic Heart Disease.

A Case for discussion and an overview on Pyrexia of Unknown Origin.