Corticosteroid therapy and adverse effects — branching viva

Opening — the weaning plan on the ward

Examiner: A four-year-old on daily prednisolone for frequently relapsing nephrotic syndrome has been on a pharmacologic dose for three months. Walk me through the corticosteroid pharmacology and how you would wean her. ^[9]

Candidate (model): Prednisolone is about four times as glucocorticoid-potent as hydrocortisone, with slight mineralocorticoid activity. The equivalent-dose anchor I keep at the bedside is hydrocortisone 20 mg equals prednisolone 5 mg equals methylprednisolone 4 mg equals dexamethasone 0.75 mg. Because she has been on a pharmacologic dose well beyond two to three weeks, her hypothalamic-pituitary-adrenal axis is suppressed and she cannot mount a cortisol response to stress. I would not stop abruptly. I would taper the prednisolone to a physiological equivalent — about hydrocortisone 8 to 10 mg per square metre per day — then step it down every one to two weeks while she stays well. Before I stop, I would test the axis with a morning cortisol or a short Synacthen test, and I would keep the sick-day rules and emergency hydrocortisone in place through the recovery window, because full adrenal responsiveness lags behind the wean. ^[9]