Unusual cause of diarrhoea

I think this lucky gentleman is one of those that I will remember forever. He presented to hospital with diarrhoea. I was the first to see him in our ward. I took a history from him - he lied all the way (ok, I'm being too harsh, he has dementia and was actually two years behind us as he was telling me stories of his life two years back...). I felt a mass on his abdomen arising from the pelvis which was dull on percussion and diagnosed urinary retention, the diagnosis confirmed by bladder scan and treated by urethral catheterisation. Such a brilliant diagnosis! It made me feel so elated for several days. Diarrhoea then settled, no particular cause was found. In the interim he also developed conjunctivitis and coryzal (cold) symptoms. We were going to send him back to his nursing home when the nursing staff reported some rash. It didn't bother him at all, in fact he looked so much more alert and alive. One day after on yesterday's ward round, we saw the rash again and it has spread all over his body. (Maculopapular, blanching, discrete at first then coalescing). It looks like a rash from drug reaction, but he has not been started on any new drug. The only other differential diagnosis would be measles. They actually really look like measles. We then had a look into his mouth - there were white spots all over particularly the buccal mucosa. Medical students - what are these spots called?

If you are a medic, I hope you can sense our excitement by now! Medical staff who are not immunised and might be pregnant were told to stay off - which was a bit too late I think because the disease is most contagious before the rash appears. Another thing was that he was next to another patient who is immunocompromised on chemotherapy. He was isolated in a side room after that. When typing up the notes, I had to tell the geriatricians how to spell 'Koplik' as it was really not something that they expect to encounter in their specialty.

Extremely exciting stuff!

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