Tests Before Immunosuppression

Before starting systemic corticosteroids, it is important to confirm the diagnosis and also have leukaemia / malignancy considered and excluded - Full [complete] blood count and peripheral smear / blood film are indicated and bone marrow should be considered where there is clinical concern.

Before starting immunosuppression (methotrexate or biologics), it is important to check the following:

• Full [complete] blood count.
• Acute phase reactants (CRP, ESR, +/- Ferritin).
• Liver function tests. 
• Urea and Electrolytes / Creatinine.
• Infection screen to exclude:

• Tuberculosis by chest radiograph and QuantiFERON® Gold. Mantoux (Tuberculin Skin Test) would be the alternative where QuantiFERON® Gold is not available. The Mantoux test must be interpreted in the clinical context as well as given the patient’s past history (i.e., child has received BCG vaccine as a baby - check for scar of BCG vaccination).
• Hepatitis B and C and HIV status. In many countries this is routine practice but there are local variations pending prevalence, at risk populations and other risk factors being present. The child may have received Hepatitis B vaccine.
• Serology for Varicella and Measles status. If the child is negative and there is a window of time before starting immunosuppression then vaccination should be considered - specialist advice is warranted.