Explaining acute bacterial rhinosinusitis, the antibiotic decision and the safety-net — OSCE

Candidate instructions (8-minute station)

You are the paediatric registrar in the emergency department. A 5-year-old has had a runny nose and cough for twelve days after a cold, was given oral amoxicillin on day three by the family doctor for a sore ear, and over the last two days the fever has returned and the nasal discharge has become thicker and more purulent. The child is systemically well, with bilateral mucopurulent nasal discharge and no orbital or neurological signs. The parent is anxious and wants to know whether the antibiotic syrup should have worked by now, whether this is just a lingering cold, whether a new antibiotic is really needed, and what to watch for. [1]

Your tasks are: [1]

1. Explain the diagnosis of acute bacterial rhinosinusitis in plain language and why it is more than a lingering viral cold. [1]
2. Explain why an antibiotic is now appropriate after twelve days with worsening, having previously not been needed for the viral cold, and outline the regimen and the forty-eight to seventy-two-hour reassessment. [1] [2]
3. Explain the role of saline irrigation and the intranasal corticosteroid as part of the plan. [2]
4. Give a clear, specific safety-net for the signs that would mean the infection has spread towards the eye or the brain and needs urgent escalation. [9]

You are not expected to detail the antibiotic pharmacology to the parent, but you should explain the plan clearly and honestly, including that most children recover fully. [11]

Examiner prompt to the actor (parent)

"He was given the antibiotic syrup on day three for his sore ear, so why has it got worse again now — did that medicine not work? His nose has just kept running and now the fever is back. Is this not just a stubborn cold? Do we really need another antibiotic, and what should I be worried about?" [1]

Marking domains

• Frame and explanation of the diagnosis (3): explains acute bacterial rhinosinusitis as a bacterial infection that has taken hold in the sinuses after the cold blocked the drainage, which is why the symptoms have persisted beyond ten days and worsened again; is honest that it is more than a lingering viral cold but treatable; reassures that the earlier amoxicillin was for a different problem (the ear) and was not a failed treatment for the sinus. [1]
• The antibiotic decision with the regimen and reassessment (3): explains that because the cold has run on for over ten days and then worsened, an antibiotic is now the right treatment, unlike the first ten days of a viral cold where antibiotics do not help; names a high-dose amoxicillin-clavulanate course for ten to fourteen days; explains that the team will check the response at forty-eight to seventy-two hours and reconsider the diagnosis if there is no improvement. [1] [2]
• Adjuncts and expectation (2): explains the saline irrigation to wash the nose and the intranasal corticosteroid to reduce the swelling and help drainage, alongside the antibiotic; sets a realistic expectation that most children recover fully and that the discharge and cough should settle over the course. [2]
• Safety-net for orbital and intracranial spread (2): tells the parent to seek urgent help if the child develops swelling, redness or pain around the eye, a staring or bulging eye, double or reduced vision, a severe headache, a stiff neck, repeated vomiting, drowsiness, a fit, or a worsening illness with a high swinging fever — because those signs would mean the infection may be spreading towards the eye or the brain and would need an urgent scan and specialist care. [9] [11]

Model answer — the explanatory script

"Thank you for bringing him in. I can see he has been miserable with this. I have examined him carefully, and I want to explain what I think is going on. This is more than a lingering cold now. When a cold blocks the narrow drainage channels of the sinuses behind the nose, the mucus gets trapped, and after about ten days bacteria can take hold there. That is what has happened here — his runny nose and cough have gone on for twelve days without improving, and then he has got worse again with the fever returning. That pattern tells us it has turned into a bacterial sinus infection, which we call acute bacterial rhinosinusitis." [1]

"The antibiotic syrup he was given on day three was for a sore ear, and it was not a failed treatment for the sinus — this sinus problem has only declared itself now, after ten days. The good news is that it does respond to the right antibiotic. Because it is a bacterial sinus infection, this time an antibiotic is the right thing, where for the first ten days of an ordinary cold they do not help. I will prescribe a high-dose amoxicillin-clavulanate course — that is an antibiotic related to the one he had, but dosed specifically for the sinus and with an extra ingredient to cover the bacteria that cause this. He will take it twice a day for ten to fourteen days." [1] [2]

"Alongside the antibiotic, I would like him to use saline rinses or spray to wash the mucus out of his nose, and a steroid spray to reduce the swelling and help the sinuses drain. We will check how he is at two to three days — if he is not starting to improve by then, we will look again at the diagnosis and whether he needs anything more. Most children recover fully with this approach." [2]

"The one thing I most want you to watch for is whether the infection spreads towards the eye or the brain, which is the serious complication we are guarding against. Please bring him straight back or call for urgent help if he develops swelling, redness or pain around the eye, a staring or bulging eye, double vision or says he cannot see properly, a severe headache, a stiff neck, repeated vomiting, becomes drowsy or hard to wake, has a fit, or becomes more unwell with a high fever that keeps spiking up and down. Any of those would mean we need to scan him urgently and bring in the specialist teams. Those signs are not common, but they are the ones that matter, and I would rather you sought help than waited." [9] [11]

"I know this is a lot to take in. The short version is this: his cold has turned into a bacterial sinus infection after twelve days, it needs a specific antibiotic for ten to fourteen days with nose washes and a steroid spray, a check at two to three days, and a clear list of eye and brain warning signs to watch for. We will keep an eye on him together." [1]