Table 5

 Examples of second line investigations only to be undertaken if symptoms/signs or first line investigations suggest an alternative diagnosis

CT, computed tomography, MRI, magnetic resonance imaging; USS, ultrasound scanning.
Blood testsAntinuclear antibody, immunoglobulins, celiac serology, Lyme disease, toxoplasma, brucellosis antibodies, copper and caeruloplasmin, cortisols and synacthen test, B12, folate, ferritin, blood carboxyhaemoglobin
UrinalysisOrganic acids, amino acids, toxicology screen
ImagingChest x ray, MRI, CT or USS