Gammaglutamyl transferase is elevated in a number of hepatobiliary conditions (nearly all forms of biliary disease and cholestasis will be associated with a raised GGT (1)). These include:
As a glucocorticoid , the lipophilic structure of prednisolone allows for easy passage through the cell membrane where it then binds to its respective glucocorticoid receptor (GCR) located in the cytoplasm. Upon binding, formation of the GC/GCR complex causes dissociation of chaperone proteins from the glucocorticoid receptor enabling the GC/GCR complex to translocate inside the nucleus. This process occurs within 20 minutes of binding. Once inside the nucleus, the homodimer GC/GCR complex binds to specific DNA binding-sites known as glucocorticoid response elements (GREs) resulting in gene expression or inhibition. Complex binding to positive GREs leads to synthesis of anti-inflammatory proteins while binding to negative GREs block the transcription of inflammatory genes. 
The approximate incidences of adverse reactions reported in pediatric patients with JRA treated with oral, weekly doses of methotrexate (5 to 20 mg/m²/wk or to mg/kg/wk) were as follows (virtually all patients were receiving concomitant nonsteroidal anti-inflammatory drugs, and some also were taking low doses of corticosteroids): elevated liver function tests, 14%; gastrointestinal reactions� (., nausea, vomiting, diarrhea), 11%; stomatitis, 2%; leukopenia, 2%; headache, %; alopecia, %; dizziness, %; and rash, %. Although there is experience with dosing up to 30 mg/m²/wk in JRA, the published data for doses above 20 mg/m²/wk are too limited to provide reliable estimates of adverse reaction rates.