Explain a severe drug eruption to a parent — OSCE

Candidate instructions

You are the paediatric registrar. You have five minutes to speak with Mrs Patel, whose seven-year-old son Arjun was started on phenytoin for new-onset epilepsy six weeks ago and has just been admitted with a fever, a widespread red rash, a swollen face, enlarged glands, and blood tests showing eosinophilia and hepatitis. You have made the diagnosis of DRESS, a severe drug reaction to the phenytoin. Mrs Patel is frightened and confused — the medicine was meant to help Arjun, not make him ill. Explain what DRESS is in plain language, why the phenytoin caused it, what the treatment and the outlook are, and the plan for his epilepsy going forward — honestly and without overpromising. Answer her questions, check her understanding, and agree a plan with her. [3]

Actor brief (parent — Mrs Patel)

You are frightened and confused. Arjun's epilepsy diagnosis was already a shock, and now the medicine that was supposed to protect him has made him ill with a fever and a terrible rash. You want to know: (1) What is wrong with him — is it an allergic reaction? (2) Did the epilepsy medicine cause this, and did I do something wrong by giving it? (3) Will he be all right? (4) What is the treatment, and will he need it forever? (5) What about his epilepsy now — can he still be treated? Push back if the candidate uses jargon, brushes off your worry, or overpromises that everything will simply be fine. You calm when you feel heard and given honest, clear information. [3]

Exemplar candidate approach

Open and acknowledge. "Mrs Patel, please sit down. I can see how frightened you are, and I completely understand — Arjun has been through so much already, and now this. I want to be honest and clear with you about what is happening, because the good news is we know what it is and we know how to treat it. Please stop me with any question at all." [3]

Explain what is wrong. "Arjun has what we call DRESS — it stands for drug reaction with eosinophilia and systemic symptoms, which is a complicated name for a serious kind of reaction to a medicine. His immune system has over-reacted to the phenytoin, and it is causing inflammation not just in his skin but in his liver as well, which is why his blood tests are abnormal. It is not a simple allergy like a rash from penicillin — it is a more serious reaction that we take very seriously and treat actively. He is in the right place." [1]

Explain why the phenytoin caused it, and reassure about blame. "Yes, the phenytoin caused this, but I want to be very clear — neither you nor Arjun did anything wrong. This happens because some people's bodies break down the phenytoin in a slightly different way that lets a build-up occur, and that build-up triggers the immune system. It started about six weeks into the medicine, which is actually typical for this kind of reaction — it is a delayed reaction, not an immediate one, which is why no one could have predicted it. You did exactly the right thing by bringing him in." [1]

Be honest about the outlook. "I want to be honest with you. This is a serious reaction, and we are going to treat it actively. Most children recover fully with the right treatment, but it can take weeks, and there is a small chance it could get worse before it gets better, or come back even after we stop the medicine. That is why we are keeping him in hospital, watching his blood tests closely, and treating him with a medicine called a corticosteroid that calms the inflammation down. I will not pretend it is nothing, but I also want you to know that we have a clear plan." [2]

Explain the treatment. "The treatment has three parts. First, we stop the phenytoin immediately and completely — that is the most important step. Second, we give him a corticosteroid, which is a medicine that switches off the inflammation, and we will keep him on it for some weeks and then reduce it slowly, because stopping too quickly can make the reaction come back. Third, we watch his liver and his blood counts closely. He will need to stay in hospital for a while, and we will involve our dermatology and allergy teams. He will not need this medicine forever — once the reaction settles, we taper it off." [2]

Address the epilepsy and the future. "For his epilepsy, the phenytoin is now off the table forever — he must never have it again, or any of its close relatives, because they could cause the same reaction. But that does not mean we cannot treat his epilepsy. There are several other medicines that work in a completely different way and are safe for him, and our neurology team will help us choose the right one. I will give you a written card listing what he must avoid, and we will make sure every doctor he sees knows about it. His epilepsy can absolutely still be well controlled." [1] [3]

Check understanding and agree a plan. "Can I check — what is your biggest worry right now, and has anything I have said been unclear? Here is the plan for today: we stop the phenytoin, we start the corticosteroid, we monitor his liver and bloods, and we bring in the specialist teams. I will come back and update you regularly, and you can ask me anything at any time. We are going to get through this together." [3]

Mark scheme (10 marks)

• Empathy and relationship (2): acknowledges fear and the burden of the epilepsy diagnosis, sits and listens, plain language, does not dismiss or overpromise. [3]
• Explains DRESS in plain language (2): a serious immune over-reaction to the phenytoin causing skin and liver inflammation, not a simple allergy. [1]
• Reassures about blame and explains the cause (2): delayed reaction at six weeks, a difference in how the body breaks down the drug, nothing the parent did wrong. [1]
• Is honest about outlook and treatment (2): serious but treatable, corticosteroid for weeks tapered slowly, stop the phenytoin, hospital monitoring, specialist teams. [2]
• Addresses the epilepsy and checks understanding (2): phenytoin and its relatives avoided lifelong, safe alternatives exist, written allergy card, neurology partnership, checks the parent's understanding and worry. [1] [3]