Mark Penny is a 19-year-old undergraduate who visits the pharmacy concerned about his ear. He recently returned from a trip to Thailand. He wants to speak to the pharmacist about an ear piercing he had while on holiday.

Mark went to see a professional piercer who pierced his right ear at the tip (pinna) with a titanium stud. The ear was swabbed with an unknown solution and the ear was pierced from what Mark assumed was a sterile packet. He was told to keep it dry but went swimming most days. One week after the piercing, the ear started to get red and increasingly more painful and was discharging a watery and blood-stained fluid.

A friend recommended a doctor in Bangkok, who started a course of cefalexin 500mg qds, which Mark has taken diligently – he is on day six out of seven.

However, while the infection initially settled slightly, the whole ear is now an angry red, hugely swollen and extremely painful. The skin appears wet and Mark reports feeling a little shivery and ‘under the weather'.

What do you think is the problem? What should you do?

The presentation suggests cellulitis, an acute bacterial infection of the dermis and subcutaneous tissue that arises following damage to the skin. The most common infective agents are Streptococci and Staphylococci, although after exposure to water, as in this case, other organisms can be implicated. Mark's symptoms, both local and systemic, are typical. The symptoms, together with the acute, unilateral presentation, are highly diagnostic.

Mark would not be considered high risk as he has no other underlying medical condition, nor is he immunocompromised. He does not have facial or periorbital cellulitis and is not at the extremes of age. If he were high risk, he would need urgent hospital admission for IV antibiotics. For other reasons for immediate admission, see http://cks.nice.org.uk/cellulitis-acute#!scenariorecommendation

The pharmacist decides to refer Mark urgently. He speaks to the practice nurse and arranges for Mark to be seen later that morning.

How will Mark's condition be treated?

For someone at lower risk, treatment would be with oral antibiotics. High dose flucloxacillin, erythromycin or clindamycin are the usual drugs of choice, although facial cellulitis is treated first line with co-amoxiclav. Cefalexin would not routinely be used.

It is not usual to take a swab, but this may be considered in Mark's case because of the complication of his exposure to sea water. In this case doxycycline may be appropriate in combination with flucloxacillin (or erythromycin/clindamycin).

What general advice can the pharmacist offer Mark?

The pharmacist can suggest Mark takes paracetamol or ibuprofen for pain while he is waiting for his appointment. He should drink adequate fluids to prevent dehydration.

Further reading

Nice Clinical Knowledge Summaries (2012). Cellulitis.

Dermnet (2014). Cellulitis.

If you identify a gap in your knowledge, you might want to consider making a CPD entry. C+D's Practical Approach archive is available online

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