Additional investigations

Specific blood tests and microbiology may be required for certain indications and these are listed below:

• travel to malarial country - repeated blood films
• IV drug use or at risk - hepatitis serology (A-E), for HIV or Hepatitis HIV testing
• thyrotoxicosis - T4, T3, TSH
• suspected connective tissue disorder - ANF, anti-DNA antibody, CRP
• specific agent suspected - serial titres for EBV, CMV, influenza, Toxoplasma, Lyme disease, chlamydia, salmonella, Borrelia recurrentis, Q fever, leptospirosis

Other procedures however that may also be considered are:

• abdominal ultrasound:
  • intra-hepatic, subphrenic or paracolic abscesses
• white cell labelling:
  • this may show a localised abcess, empyema or osteomyelitis
• bone scan:
  • this again may identify osteomyelitis or metastatic bone disease
• CT and MRI:
  • lymphoma or covert tumours
• echocardiography:
  • infective endocarditis
• bone marrow:
  • leukaemia or culture for miliary TB
• biopsy:
  • either endoscopically or percutaneously of suspected area
• repeat history, examination and certain investigations:
  • if origin of fever remains unknown