10th August 2020

An elderly patient comes to see you as she has developed a sore lump on her shin

An elderly patient comes to see you as she has developed a sore lump on her shin. It is tender and erythematous and around 3cm in diameter and has come on over the past few days. On questioning, she admits to some malaise and arthralgia around the same time. She also has a dry cough that has been present for a week or so. She is febrile on examination.

Which of the following is the most likely cause? 

Select the SINGLE most appropriate option from the list below. Select ONE option only.