This 10-year-old boy was just one of a procession of children brought to my emergency surgery. The story was familiar – a mild fever, catarrh, sore throat and a cough. It looked like he was probably developing some conjunctivitis, too. Otherwise he seemed reasonably well, had no significant past medical history and was on no medication. The parents' main concern was some ‘spots' they had noticed in his mouth, which they thought might have been causing his sore throat.
First instinct
Examination showed clusters of small, white lesions on his soft palate and buccal mucosa. He had a few mildly enlarged cervical nodes too, and was obviously febrile. There were no similar lesions elsewhere, he had no rash and there was no history of contact with any particular infectious disease. My gut reaction was that this was just a non-specific viral illness – it's not unusual for these to produce oral lesions.
Differential diagnosis
- Herpangina
- Hand, foot and mouth disease
- Herpetic stomatitis
- Other viral illness
- Aphthous ulcers.
Off the top of my head, I could think of three well-defined viral illnesses that could present in this way. Primary herpetic stomatitis is one we see fairly often – although usually in younger children, with more extensive oral lesions and ulceration, and markedly enlarged lymph nodes.
Hand, foot and mouth disease is common and can affect this age group – but there were no signs of any lesions on the hands or feet. So this left herpangina, which is caused by a Coxsackie virus. The lesions and the distribution – towards the back of the oropharynx – were certainly typical, although it's not a diagnosis we make in general practice very often.
The only other thought that crossed my mind was aphthous ulceration. But the lesions were not typical, they were unusually numerous and he had no history of previous problems – besides, the fever and coryza pointed very strongly towards a viral aetiology.
So I favoured the ‘non-specific viral illness' diagnosis – though, if I was pushed to give a label, herpangina seemed to be the most likely.
The hidden clue
I gave the usual advice and was surprised to see that the child was slotted in as an ‘urgent' at the end of my surgery a couple of days later. By now, the oral lesions were less of a concern – the parents were much more worried about the florid and extensive erythematous blanching rash that had developed the day after I'd seen him. He was clearly more unwell, though not ill enough to need admission. I'd never encountered a real case of measles before, but this certainly resembled pictures I'd seen of the exanthem.
This led me to check his immunisation status – and there was the clue, in his notes: ‘No previous MMR vaccination.'
Getting on the right track
In retrospect, the oral lesions must have been Koplik's spots – part of the measles prodrome. Given that measles is a notifiable disease, laboratory confirmation of the diagnosis was required, so saliva samples were sent.
The patient made an uncomplicated recovery over the next week or so, and, subsequently, the lab results confirmed that he had suffered measles.
Dr Keith Hopcroft is a GP in Laindon, Essex
